Riparian Tree and Shrub Propagation Handbook
Transcripción
Riparian Tree and Shrub Propagation Handbook
RIPARIAN TREE AND SHRUB PROPAGATION HANDBOOK RIPARIAN TREE AND SHRUB PROPAGATION HANDBOOK An Aid to Riverine Restoration in the Mediterranean Region Edited by María Aránzazu Prada and Daniel Arizpe CIEFBanc de Llavors Forestals Conselleria de Medio Ambiente, Agua, Urbanismo y Vivienda, Generalitat Valenciana Avenida Comarques del País Valencià 114 46930 Quart de Poblet, Valencia, España © 2008 Generalitat Valenciana © texts, illustrations and plates: the authors Illustrations: Faustino Díez Unless otherwise specified Emilio Laguna Clematis flammula, Coriaria myrtifolia, Dorycnium rectum, Flueggea tinctoria, Lonicera implexa María Aránzazu Prada Liquidambar orientalis, Myrtus communis, Populus orientalis, Salix amplexicaulis, Salix pedicellata and cover Plates: Gabriel SegarraMoragues Salix plates ISBN: 9788448249656 Legal Deposit no.: V38782008 Design: Essência ROFFdesign (http://essencia.roff/pt) Layout and Printing: Gràfiques Vimar (http://www.vimar.es) English edition: copy editing by Mary Georgina Hardinge Preface My opportunity to contribute began to take shape when I became aware of the riparian ecological res toration efforts at the Higher Institute of Agronomy at the Technical University of Lisbon. That frame work prompted me to launch a project to establish a working group with other European institutions that share the same concerns. The Ripidurable Pro ject was presented in April 2003 and approved to wards the end of that year. It was launched with the goal of creating a forum for communication and co llaboration between those responsible for the ma nagement and restoration of riparian areas and the academic and research institutions with knowledge and expertise in those habitats. The group could co rrelate the problems detected with the existing kno wledge in pursuit of the solution to those problems and develop specific tools, including some case stu dies, which could be offered to society. One of the problems that most caught my attention was the great difficulty that institutions and com mercial companies involved with the recovery of ri parian ecosystems had in obtaining suitable plants for this purpose. Generally, companies that market plants do not have suitable reproductive material for these interventions, from the standpoint of either external quality or adaptability. Therefore, the solu tion has historically depended on acquiring plants from other countries and, in many cases, on orna mental varieties or fastgrowing hybrid poplars. The publication of this riparian species propagation guide is intended as a tool to help resolve the afo rementioned situation and stimulate the produc tion of plant materials from local sources. The team from the Forest Seed Bank of the Regional Govern ment of Valencia has contributed significantly to the preparation of this guide. This group combines hard work and rigour with the institution's lengthy experience in the management and effective short term use of germplasm, as well as its valuable work on longterm conservation, a legacy for future generations. The team that developed this guide has made a sig nificant contribution to both scientific and techni cal knowledge through their extensive experience and current academic research. The guide can now be used by companies and institutions that intend to produce plants for the great task of pursuing ade quate recovery of riparian ecosystems. By 2015, following the Water Framework Directive, rivers should be classified as having good ecological status, in accordance with the reference conditions. It is our fervent hope that this guide will help to en sure that this status is achieved within the planned time and with the care that nature deserves, by ai ding the production of quality plants that safeguard the genetic heritage of each species. The authors of this guide deserve our gratitude for sharing their experience and knowledge with us all. The editors, Arantxa Prada and Daniel Arizpe, des erve particular appreciation for the effort that they have put into this project and for the perseverance they have shown in making this book a reality. Ana Mendes Higher Institute of Agronomy Technical University of Lisbon 5 Preface The habitats that are perhaps most intensely modi fied by man are riverine habitats. I became aware of this situation during numerous visits to Portuguese riparian environments in search of a Cetti’s warbler or a kingfisher. This knowledge sparked in me a des ire to contribute, in my own small way, to the reco very of these degraded environments for the benefit of nature, of mankind and ultimately, for the pre servation of biodiversity. Contributors Maria Helena Almeida Universidade Técnica de Lisboa, Instituto Superior de Agronomia, Centro de Estudos Florestais, Tapada da Ajuda, 1349017 Lisbon, Portugal José Vicente Andrés Avenida Salvador Allende 75, esc. 14, 4ºD, 50015 Zaragoza, Spain Juan Añíbarro Viveros Fuenteamarga SL, polígono 7, parcela 18, 47260 Cabezón de Pisuerga, Valladolid, Spain Daniel Arizpe CIEFBanc de Llavors Forestals, Área de Gestión de Re cursos Forestales y Conservación Ambiental, Conselle ria de Medio Ambiente, Agua, Urbanismo y Vivienda, Generalitat Valenciana, Avenida Comarques del País Valencià 114, 46930 Quart de Poblet, Valencia, Spain Antonio del Campo Dep. Ingeniería Hidráulica y Medio Ambiente, Escuela Técnica Superior de Ingenieros Agrónomos, Univer sidad Politécnica de Valencia, Camí de Vera s/n, 46002 Valencia, Spain Esperanza Campos CIEFBanc de Llavors Forestals, Área de Gestión de Re cursos Forestales y Conservación Ambiental, Conselle ria de Medio Ambiente, Agua, Urbanismo y Vivienda, Generalitat Valenciana, Avenida Comarques del País Valencià 114, 46930 Quart de Poblet, Valencia, Spain Carla Faria Universidade Técnica de Lisboa, Instituto Superior de Agronomia, Centro de Estudos Florestais, Tapada da Ajuda, 1349017 Lisbon, Portugal Cándido Gálvez Semillas Silvestres S.L., Carretera de Santa María de Trasierra km 2, 14012 Córdoba, Spain Jose Luis García Caballero Junta de Castilla y León, Servicio Territorial de Medio Ambiente León, Avenida Reyes Leoneses 145ºC (Edificio Europa), 24071 León, Spain Pablo Jiménez Universidade Técnica de Lisboa, Instituto Superior de Agronomia, Centro de Estudos Florestais, Tapada da Ajuda, 1349017 Lisboa, Portugal Fernando Martínez Sierra Junta de Castilla y León, Servicio Territorial de Medio Ambiente León, Avenida Reyes Leoneses 145ºC (Edificio Europa), 24071 León, Spain Eduardo PérezLahorga Área de Gestión de Recursos Forestales y Conserva ción Ambiental, Conselleria de Medio Ambiente, Agua, Urbanismo y Vivienda, Generalitat Valenciana, Calle Francisco Cubells 7, 46011 Valencia, Spain Mari Carme Picher CIEFBanc de Llavors Forestals, Área de Gestión de Re cursos Forestales y Conservación Ambiental, Conselle ria de Medio Ambiente, Agua, Urbanismo y Vivienda, Generalitat Valenciana, Avenida Comarques del País Valencià 114, 46930 Quart de Poblet, Valencia, Spain María Aránzazu Prada CIEFBanc de Llavors Forestals, Área de Gestión de Recursos Forestales y Conservación Ambiental, Con selleria de Medio Ambiente, Agua, Urbanismo y Vi vienda, Generalitat Valenciana, Avenida Comarques del País Valencià 114, 46930 Quart de Poblet, Valencia, Spain Jesús Rueda Junta de Castilla y León, Dirección General del Medio Natural, Calle Rigoberto Cortejoso 14, 47071 Valla dolid, Spain Pilar Ventimilla CIEFBanc de Llavors Forestals, Área de Gestión de Recursos Forestales y Conservación Ambiental, Con selleria de Medio Ambiente, Agua, Urbanismo y Vi vienda, Generalitat Valenciana, Avenida Comarques del País Valencià 114, 46930 Quart de Poblet, Valencia, Spain 7 Contributors Neus Albert CIEFBanc de Llavors Forestals, Área de Gestión de Re cursos Forestales y Conservación Ambiental, Conselle ria de Medio Ambiente, Agua, Urbanismo y Vivienda, Generalitat Valenciana, Avenida Comarques del País Valencià 114, 46930 Quart de Poblet, Valencia, Spain Contents Introduction 17 Species fact sheets (M. Aránzazu Prada, Daniel Arizpe, Juan Añíbarro, Jesús Rueda, Neus Albert, Esperanza Campos, Mari Picher, Pilar Ventimilla, Cándido Gálvez, Carla Faria, Pablo Jiménez) 19 22 27 30 33 36 40 43 46 50 53 55 59 63 67 70 73 76 79 83 87 90 94 97 101 105 109 113 116 119 124 127 130 135 138 141 Fact sheet contents Alnus glutinosa (L.) Gaertn. Arbutus unedo L. Celtis australis L. Cercis siliquastrum L. Clematis flammula L. y C. vitalba L. Coriaria myrtifolia L. Cornus sanginea L. Crataegus monogyna Jacq. Dorycnium rectum (L.) Ser. Flueggea tinctoria (L.) G.L. Webster Frangula alnus Mill. Fraxinus angustifolia Vahl. Hedera helix L. Humulus lupulus L. Laurus nobilis L. Ligustrum vulgare L. Liquidambar orientalis Mill. Lonicera etrusca G. Santi y L. implexa Aiton Myrtus communis L. Nerium oleander L. Pistacia lentiscus L. Platanus orientalis L. Populus alba L. Populus nigra L. Populus tremula L. Prunus mahaleb L. Prunus spinosa L. Rubus ulmifolius Schott Salix spp. Sambucus nigra L. Tamarix spp. Ulmus minor Mill. Viburnum tinus L. Vitex agnuscastus L. Vitis vinifera subsp. sylvestris (C.C. Gmelin) Hegi 147 149 Appendices Variation and adaptation 152 Seed handling (Helena Almeida, Carla Faria) (M. Aránzazu Prada) 158 Nursery culture 162 Cutting propagation 165 169 171 172 174 190 195 (Antonio del Campo) (Daniel Arizpe, M. Aránzazu Prada) Stool beds (José Luis García Caballero, Fernando Martínez Sierra, Jesús Rueda) Master certificate (M. Aránzazu Prada) Plant passport (Eduardo PérezLahorga) Populus spp. (diagnostic traits) (José Vicente Andrés, M. Aránzazu Prada) Salix spp. (distribution and diagnostic traits) (José Vicente Andrés, M. Aránzazu Prada) Tamarix spp (distribution and diagnostic traits) (José Vicente Andrés, M. Aránzazu Prada) Glossary 9 Contents 11 1 11 Introduction Introduction Riparian vegetation is of great ecological interest due to the part it plays in numerous processes that have to do with the quality of the physical environment and the life cycles of the aquatic and terrestrial fauna associated with fluvial systems. It connects different habitats and improves the quality of other terrestrial, aquatic or coastal/marine systems. Fluvial systems in the Mediterranean region have been greatly altered by human activity. Their chan nels and riverside areas have been transformed, first into farmland and more recently into urban deve lopments. Human activity has also regulated flow vo lumes, canalisation projects have destroyed the connectivity between river courses and alluvial plains and surface and underground water reserves are ove rexploited. These alterations have directly or indi rectly affected the natural riverside vegetation by reducing its biodiversity, scattering its populations and, in some extreme cases, making it disappear en tirely from large stretches of rivers. In the face of such general deterioration, restoring fluvial ecosystems by recovering natural hydrological regimes is an unavoidable task. Such interventions may require plantation projects as a means of reco vering riverside vegetation in the short term. Other specific objectives might aim at enriching the flora or introducing species that may have disappeared as a result of human activity or that play a vital role in plant/animal interactions. An additional objective could be the development of tree coverage to com pete with and eliminate alien species. Planting may also be advisable in order to increase the genetic base of populations, especially when these have suf fered a decrease in the number of individuals or a loss of geneflow rates due to human pressure, or when inappropriate use has been made of reproduc tive materials in the past, especially as regards spe cies with vegetative propagation patterns. After these interventions, however, the river itself will eventually model the structure and the dynamics of its riparian vegetation. In any event, the generation of reproductive mate rials for use in river restoration projects must try to ensure the viability of the newly introduced popula tions without impairing existing genetic resources. This is achieved, first of all, by proper species selec tion. Since these plantings are not made for com mercial purposes, native taxa and materials of local provenance should be favoured whenever possible. The genetic base of the chosen materials should also be as wideranging as available resources permit, in order to enhance the adaptability of new popula tions. Alien species – some of which have already become naturalised in riverside areas of the Medite rranean region – must be particularly avoided, as well as species that may hybridise with the local ones. This guide has been conceived as a support tool for nursery managers and for others who are not spe cialists but are involved, in one way or another, in the production of riparian plant species for hydrolo gical restoration projects. It offers useful data on the production of seeds, parts of plants and plants be longing to a large series of tree, shrub and lianoid species that may be employed in fluvial systems of the Mediterranean region. It provides information on species that are dominant in the riparian vegetation of the region, on species whose propagation may be of interest due to their potential interaction with some species of fauna and on species that are tradi tionally used for hydrological restoration purposes. Although some of the taxa included are not strictly riparian, they originate in the Mediterranean shrub and forest communities and can develop optimally in these environments, especially in extremely dry areas. The information is presented in the form of fact she ets that include details of the production of repro ductive materials – from collection to conservation –, the physical characteristics of seeds and the most appropriate methods for producing plants generati vely and vegetatively. General data on each taxon are 13 Introduction The fluvial systems of the Mediterranean region, with their specific dynamics and environmental condi tions, less extreme than those of surrounding systems, are home to a mosaic of habitats with a high degree of biodiversity and serve as a migration path for many species of flora and fauna. They also play a critical role in the life of human communities, which use their resources and also benefit from them as leisure spaces. also provided: geographical distribution, ecology, ta xonomic identification features and reproductive biology. These technical sheets include additional de tails that may be of use for improved management of reproductive materials. In particular, information about intraspecific variation – and its implications for collecting and using materials – is provided whe never possible with a view to promoting the conser vation of genetic resources. A series of appendices deals with certain specific matters that are directly related to the production and use of forest reproductive materials, such as in traspecific genetic variation and its relevance in terms of population adaptability, practical aspects of the production and conservation of seeds and parts of plants and the European regulations applicable to the production, transport and marketing of some species included in the present guide. Another appendix has tables and figures which aim to make it easier to identify species of the genera Po pulus, Tamarix and Salix that can be found in the Eu ropean Mediterranean region. It was also considered helpful to provide a glossary of the scientific and technical terms employed that are not commonly used by the intended users of this guide. We hope that the guide will prove a useful manual for plant producers and contribute to the conserva tion and improvement of our Mediterranean riverine environments, which are part of our natural and cul tural heritage. We would like to thank Christine Fournaraki (Medi terranean Agronomic Institute of Chania, Greece), Isabel Montávez (Intersemillas SA, Spain), Fabio Go rian (CFSCentro Nazionale per lo Studio e la Con servazione della Biodiversità Forestale, Italy), Despina Paitaridou (Ministry of Rural Development and Food, Greece), Jesús Martínez y Sisco Bosch (Banc de Lla vors Forestals de la Generalitat Valenciana, Spain), Ana Santos and Filipa Pais (Câmara Municipal de MontemoroNovo, Portugal), José Luis García Ca ballero (Junta de Castilla y León, Spain) and Valeria Tomaselli (CNR Istituto di Genetica Vegetale, Italy) for supplying valuable data included in the technical sheets, and Francisco Sánchez Saorín, Miguel Cáno vas and Manuel Balsalobre (Región de Murcia, Spain), Pedro Sánchez Gómez (Universidad de Mur cia, Spain), Begoña Abellanas (Universidad de Cór doba, Spain) and Isabel Butler (Universidad de Huelva, Spain) for their help in obtaining illustrations of willows. We are grateful to Esther Tortosa, Jesús Rueda and Ana Puertes for reviewing and correcting the original Spanish version of the text. We would also like to thank Antoni Marzo for giving us the opportunity to take part in the Ripidurable project and all our other friends at the Forest Seed Bank (Banc de Llavors Forestals) of the Regional Go vernment of Valencia who have in one way or ano ther supported the present initiative, particularly Raquel de Miguel and Gloria Ortiz. We want to give special thanks to Esther Tortosa, without whose en thusiasm and professionalism our endeavours would not have been crowned with success. Finally, we wish to express our affection, thanks and satisfaction to all our colleagues in the Ripidurable project for sharing their knowledge and information and for generating a warm atmosphere throughout the programme. We hope that we may continue to co llaborate on future projects to preserve biodiversity. The editors Introduction 14 (“... Father, tell me what they’ve done to the river to stop it singing. It slides by like a dead barbel under a foot of white foam. “... Pare, digueume què li han fet al riu que ja no canta. Rellisca com un barb mort sota un pam d'escuma blanca. Pare, que el riu ja no és el riu. Pare, abans que torni l'estiu amagui tot el que és viu. ...” Joan Manuel Serrat (Pare) 15 Introduction Father, the river’s not the river any more. Father, before the summer comes again hide every living thing ...”). 2 17 Species Fact Sheets A descriptive fact sheet has been prepared for each taxon. The fact sheets are designed to facilitate rapid ac cess to the information. They include the common names in different languages as well as the scientific name. highlighted, especially if the taxa are sympatric. It has not been possible to avoid botanical terminology in the description of the taxa but the meaning of the terms can be consulted in the glossary at the end of the book. Distribution and Ecology For a more detailed description of the taxa, reference works such as Flora Europaea or other national or re gional flora can be consulted. A map shows the distribution of the taxon in Europe and in Asian and African countries bordering the Mediterranean basin. The basic reference works for these maps are those in Bolòs and Vigo (1989), Charco (2001), the Atlas of Flora Europaea and the online “Pro grama Anthos” database. The natural distribution of some species that have been widely dispersed by man is hard to specify; for this reason, the maps for Cercis siliquastrum, Laurus nobilis, Platanus orientalis, Salix fragilis and Vitis vinifera subsp. sylvestris should be taken purely as a rough guide. The map of tamarisk distribution in the eastern Mediterranean follows the monograph on the genus by Baum (1978), completed in some cases by information from other works such as Boratyński et al. (1992), Pig natti (1982) and Zohary (1972). Because of the lack of precise information about the chorology of these species in some Eastern European countries, these maps should be taken as only a basic approximation to their distribution. The general distribution of the taxon is indicated schematically, mentioning the regions in which it is present according to the division established by Brum mitt (2001), irrespective of its abundance. There is also a list of Mediterranean basin countries that have areas with a Mediterranean bioclimate in which the species is present. This information has been taken mainly from two online databases: the digital version of Flora Europaea for its European distribution and the “Germplasm Resources Information Network” (GRIN) for its distribution elsewhere in the world. The ecology of the species is indicated in a simple, sum marised way to make it easy to understand. Diagnostic traits Information on relevant diagnostic features for identi fying the taxon is provided as concisely as possible. Dif ferences that distinguish the taxon from others with which it might quite easily be mistaken have been Reproductive biology As the phenology of reproduction and reproduction systems in the taxon is a determining cause of the ge netic configuration of populations, the most relevant data are indicated schematically. This information is re garded as important for deciding on the right strategies for collecting reproductive materials, for creating new populations and for their subsequent management. The flowering and fruit ripening periods indicated nec essarily cover a very broad range and present conside rable interannual and intersite variations, especially in widelydistributed species that grow in different cli mate conditions. The principal pollinating and dispersing agents are mentioned, although in many cases other alternatives for gene flow may exist. This situation is very common among riparian species, where water may act as a sec ondary disperser. Variation and Hybridisation Taxonomic observations are provided, such as the ex istence of subspecies or the recognition of varieties and natural hybrids. Likewise, information on the outcomes of genetic studies is provided for some species to pro mote an improvement in reproductive material han dling and in conservation of the genetic resources of the species. Seed propagation Tolerance to drying is indicated, as this is an aspect which influences the treatment given to the seed lots to a large extent. Practical information about collect ing, producing and storing seeds is included. The clean ing sequence to be employed, following the possible seed handling procedures described in the appendix, is 19 Fact Sheet Contens Fact Sheet Contents indicated concisely. The storage conditions recom mended – temperature (T), moisture content (MC) and type of container – are the standard ones for short and mediumterm storage of the materials, depending on the type of seed. The commonlyused treatments which have proved most effective for stimulating germination are indi cated. The length of the treatments is for guidance only, as they may vary depending on the provenance of the seeds. It should be said, however, that some of the species included in this guide have seeds that are dif ficult to germinate even when pretreated. Useful information has been included about optimum conditions for germinating the seeds, which can be achieved by using incubators or cultivation chambers where certain environmental factors can be controlled. The optimum temperature is given; it may be continu ous (20 ºC) or vary over a period of 24 hours (for ex ample, 30/20 ºC). The seeds of some taxa germinate well under different temperature conditions, which are indicated as possible alternatives. In the case of the varying temperatures, these are alternated: the lower temperature is usually maintained for 16 hours and the higher one for the remaining 8 hours of each 24 hour period. The seeds of many species can germinate both in the light and in the dark. Nevertheless, a photoperiod of at least 8 hours a day is recommended, usually co inciding with the higher temperature cycle in the case of an alternating temperature treatment. In some species, light stimulates germination, in which case this requirement is expressly mentioned. The data offered are only for guidance, as they may vary greatly depending on the quality of handling, cleanliness and storage conditions, as well as on the specific characteristics of each batch of seeds, which depend on the genotypes collected, the origin of the seeds and the weather conditions each year. Nursery production Fact Sheet Contens 20 For mass producing nurserygrown plants, details are given of the most appropriate sowing period and of whether pretreatment is required to stimulate germi nation. Guidelines are provided on suitable container sizes and plant ages to obtain plants with a wellde veloped root system that will withstand transplanting and be capable of penetrating the soil rapidly after planting. The containers recommended in the fact sheets should have an antispiralling system. As regards the large containers (3.5 litres), ones with a grid base raised off the ground are recommended to help the transplanted roots. Plant age is given as follows: 1/0 = 1 year, 2/0 = 2 years, 1/1 = 1 year in a 300 cm3 con tainer + 1 year in a 3.5 l container. The use of plants that are more than two years old is not recommended and they should not be more than 150 cm high. The approximate emergence time is indicated: it will vary according to the batch, the nursery’s practices, the lo cation of the nursery and the climate conditions that year. Some data for producing bareroot plants (sowing den sity, dimensions) are provided for some species, al though this traditional growing method has been replaced by containergrowing, which makes it possi ble to extend the plantingout period. The bareroot plant dimensions given (stem circumference, total height) are all maximum sizes. Vegetative propagation Information is provided about vegetative propaga tion of the species using cuttings. This is the plant production technique most commonly used for restorations and forestations of Tamarix, Salix, Pop ulus and some lianoid taxa. As plants of the other species in this guide are usually produced from seed rather than by vegetative means, most information on their vegetative multiplication is experimental or comes from the production of cultivars for ornamen tal purposes. The most suitable type of material the part of the stem or set showing the best rooting ability, a suitable num ber of internodes or cutting size and the best time of the year to take the cuttings are indicated. The concen tration of the watersoluble salt form of indolbutyric acid (KAIB) in which to soak the cutting for 1 to 5 min utes just before planting is given as a rough guide to a starting point for finetuning a rooting protocol. Fol lowing the indications of Mac Cárthaig and Spethmann (2000), the species have been divided into four groups according to the ease with which they form roots: those that do not need treatment, those that only need it only to accelerate the process (< 0.5 %), those that pose medium difficulty (0.5 %) and those that are very diffi cult to propagate (1 %). For plant production by vegetative propagation, the same kind of container as in the table for nursery pro duction of plants from seed is recommended. This guide does not aim to provide specific information about plant production by micropropagation. This kind of technique is relatively complex and costly and does not seem justified when producing plants for hydro logical restorations. However, bibliography on the sub ject is provided for further reference. References To make the text easier to read, the basic bibliography consulted systematically for describing species and infra specific taxa and references to general works from which propagation chart data have been taken have been avoided in the text itself. All these references are men tioned in the bibliography under the ‘General References’ heading. Other studies that have provided additional in formation about different aspects, mostly published in journals, are expressly cited in the text and are included as a specific bibliography so that readers can go into the subject in more depth if they wish. References Bolòs O, Vigo J (1989) Flora dels Països Catalans. Editorial Bar cino, Barcelona Boratyński A, Browicz K, Zieliński J (1992) Chorology of trees and shrubs in Greece. Sorus, Poznań Brummitt RK (2001) World Geographical Scheme for Record ing Plant Distributions. Plant Taxonomic Database Standards No. 2. Edition 2, August 2001. TDWG (online URL http://www.tdwg.org) Charco J (2001) Guía de los árboles y arbustos del norte de África. Agencia Española de Cooperación Internacional, Madrid Flora Europaea. Royal Botanic Garden Edinburgh (online URL http://rbgweb2.rbge.org.uk/FE/fe.html) Germplasm Resources Information Network (GRIN) USDA Agricultural Research Centre (online URL http://www.ars grin.gov/) Hulén E, Fries M (1986) Atlas of North European Vascular Plants. North of the tropic of cancer. Koelz Scientific Books, Königstein Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Pignatti S (1982) Flora d’Italia. Edagricole, Bolognia Programa Anthos. Fundación Biodiversidad, Ministerio de Medio Ambiente Real Jardín Botánico de Madrid, CSIC (on line URL http://www.anthos.es/) Zohari M (1972) Flora palaestina. Part two. Text. The Israel Academy of Sciences and Humanities, Jerusalem 21 Fact Sheet Contens Baum BR (1978) The genus Tamarix. The Israel Academy of Sciences and Humanities; Jerusalem Alnus glutinosa (L.) Gaertn. Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, Western and Middle Asia, Siberia, Northern Africa Mediterranean region: Portugal, España, Francia (incl. Córcega), Italia (incl. Cerdeña, Sicilia), Croacia, Bosnia y Herzegovina, Montenegro, Albania, Grecia, Turquía, Libia, Túnez, Argelia, Marruecos The alder prefers temperate to cool climates, al though it can also withstand warmer temperatures Diagnostic traits Alnus glutinosa is a mediumsized deciduous tree, not exceeding 25 m in height, with darkbrown fissured bark. It can be distinguished from Alnus cordata, a na tive of Albania, Corsica and Italy, by the shape of its leaves. In the former these are obovate or suborbicu lar, rarely elliptic, obtuse or retuse, and doubletoothed; in the latter, they are suborbicular or cordate, generally acute, and serrulate. Leaves are usually glabrous in EN: black alder, common alder EL: σκλήθρα, κλήθρα ES: aliso, alno FR: aulne glutineux, aulne noir IT: ontano nero PT: amieirocomum Betulaceae in conditions of adequate water intake. It grows on clay, silty clay, sandy or alluvial materials and re quires permanent moisture. Although it can be found on substrata with varying pH levels, it prefers acid to neutral soil types. The nodules of its roots, in sym biosis with bacteria, are effective at fixing atmos pheric nitrogen, allowing the tree to live on poor terrain. It is found by watercourses and rivers, at the bottom of valleys, in mixed deciduous forests, in flooded areas and on wet slopes, either scattered or in small populations. both species, although tufts of hair may be present in the nerve axils. The infructescence peduncle diameter is smaller in A. glutinosa (0.5–1 mm) than in A. cordata (2–3 mm). Alnus glutinosa also differs from Alnus in cana, which is found in the centre, northeast and north of Europe, in that in the latter the leaves are acumi nate and pulverulent or tomentose, in young trees at least, and the infructescences are sessile. Alnus glutinosa 22 Sex expresion ■ monoecy Flowering pendulous male catkins, erect female catkins ■ from February to June, before leaf development ■ Pollination ■ ■ anemophilous selfincompatible Two types of incompatibility systems seem to operate in Alnus glutinosa: lowered fertilisation success of the pollen parent against competition, when pollen of Variation and Hybridisation Alnus glutinosa can be pollinated by Alnus cordata. However, only natural hybrids (A. × elliptica) have been found in Corsica (Prat et al., 1992). It may often cross breed with Alnus incana (A. × pubescens Tausch) in areas where both species coexist. This hybrid exhibits female catkins with short peduncles and leaves that combine the features of both parent species. The distribution pattern of the species, in relatively small, isolated populations spread across an extensive territorial range, is associated with highly significant variations between provenances and individuals as re gards quantitative features or characteristics of adap tative relevance, (Weisgerber, 1974; DeWald and Steiner, 1986; Krstinič, 1994; Baliuckas et al., 1999). Geographical structuring of the genetic variation of the species has been observed in studies using molecular techniques (King and Ferris, 2000). At local level, a relatively low rate of genetic variation has been esti mated within populations, due to inbreeding (Kajba and Gračan, 2003), which may have been encouraged by the fact that sprouting from stumps occurs easily in Fruiting Ripening ■ ■ black, lignified infructescence, persistent after dehiscence ■ 1025 x 712 mm from September to November ■ dispersal by wind other individuals is present, or the inability to fertilise ovules when there is no competition (Steiner and Gre gorius, 1999) as may happen in isolated trees. the alder, especially in younger trees. In studies with higher levels of intrapopulational diversity, Gömöry and Paule (2002) established a spatial genetic pattern in alder populations, probably due to limited seed disper sal, which causes offspring to take root near their progenitors. Geographical structuring of genetic variation in this species makes it advisable to use local populations as a source of reproductive materials in restoration projects. It is also advisable to promote genetic varia tion in new populations by collecting material from a great many individuals at different points within the same region of provenance (Kajba and Gračan, 2003) and to ensure that the material is taken from trees that are quite distant from each other. The extensive genetic variation that has been found for features of productive interest is used to set up im provement programmes, selecting superior genotypes for these traits to create seed orchards (Krstinič and Kajba, 1991). 23 Alnus glutinosa Reproductive biology Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from September to November ■ gathering by hand, climbing or using longhandled tools sequence for dehis cent fruits ■ seed weight / kg fruit: 30260 g ■ purity: 4190 % Black alder produces seeds every year, but good crops occur once every 23 years. Climatic conditions around the time of flowering initiation, in the sum mer of the previous year and during the following spring greatly affect fruiting (Suszka et al., 1994). Collecting is carried out when the earliest fruits start to open. Seeds collected before the fruits turn brown 12 g require several months of afterripening to germinate (McVean, 1953). The light weight of alder seeds makes it difficult to remove empty seeds. If a kiln is used to open the fruits, it is recommended that tem peratures should not exceed 35 ºC; above this thres hold seeds lose their viability. Germination under controlled conditions Pregermination treatments ■ ■ fresh: without treatment dried: prechilling (38 weeks) Conditions ■ T: 5 ºC to 4 ºC MC: 48 % ■ airtight container ■ 30 / 20 ºC; 25 ºC Germination Viability ■ 3070 % Seed lot quality and germination capacity are often very low, as it is difficult to separate sound from empty seeds. Nursery production Sowing season ■ autumn or early spring, without treatment, or spring, with treatment Nursery practice bareroot: 1020 g/m2; circumference up to 46 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ Production in forestpot or container allows seedlings to be inoculated with the actinobacteria Frankia and assu Emergence ■ the first spring, complete within 35 weeks res their nodulation prior to planting (Berry and Torrey, 1985) giving rise to plants with better development. Alnus glutinosa 24 Type of cutting ■ ■ hardwood mallet semihardwood Position along the shoot basal terminal Number of internodes Size 25 cm 10 cm It is advisable to apply rejuvenation treatments in order to increase the percentage of rooting if adult ortets are used, since results are highly conditioned by the age of the parent plant (Krstinič, 1994; Martin and Guillot, 1982; Psota, 1987). There is also great clonal variation in rooting capacity (Good et al., 1978). Kruger (1982) obtained high percentages of rooting and survival and high quality root formation using hardwood mallet cuttings. Cuttings are nor mally reproduced in forestpots, in a mist environ ment (Martin and Guillot, 1982). References Collecting time winter summer Auxin concentration 0.5 % 0.5 1 % The capacity to produce shoots from the root, and, therefore, the possibility of reproducing this species by means of root cuttings has not been completely proved. Some authors (McVean, 1953; Krstinič, 1994) suggest that the alder has this capacity, although infrequently, while Fayle (1996) questions this behaviour since it has not been confirmed in the field. There are several references to in vitro propagation tri als that have achieved good results. (Garton et al., 1981; Lall et al., 2005; Perinet and Tremblay, 1987; Simon et al.,1985; Vergnaud et al., 1987). General references Specific references Ball PW (1993) Alnus Miller. In: Tutin TG et al. (eds). Flora Eu ropaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Baulickas V, Ekberg I, Eriksson G, Norell L (1999) Genetic vari ation among and within populations of four Swedish hard wood species assessed in a nursery trial. Silvae Genetica 48:1725 Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid Christensen KI (1997) Alnus Miller. In: Strid A, Tan K, (eds). Flora Hellenica. Vol 1. Koeltz Scientific Books, Königstein Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea ANPA, Roma Rocha Alfonso ML (1990) Alnus Miller. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 2. CSIC, Madrid Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Berry AM, Torrey JG (1985) Seed germination, seedling inoc ulation and establishment of Alnus spp. in containers in greenhouse trials. Plant and Soil 87:161173 DeWald LE, Steiner KC (1986) Phenology, height increment and cold tolerance of Alnus glutinosa populations in a com mon environment. Silvae Genetica 35:205211 Fayle DCF (1996) Sugar maple, black spruce and tamarack do not reproduce vegetatively from roots. Forestry Chronicle 72:283285 Garton S, Hosier MA, Read PE, Farnham RS (1981) In vitro propagation of Alnus glutinosa Gaertn. HortScience 16:758 759 Gömöry D, Paule L (2002) Spatial and microgeographical ge netic differentiation of black alder (Alnus glutinosa Gaertn.) populations. Forest Ecology and Management 160:3–9 Good JE, Bellis JA, Munro RC (1978) Clonal variation in root ing of softwood cuttings of woody perennials occurring nat urally on derelict land. International Plant Propagators Society Combined Proceedings 28:192201 25 Alnus glutinosa Vegetative propagation Kajba D, Gračan J (2003) EUFORGEN Technical Guidelines for genetic conservation and use for black alder (Alnus glutinosa). International Plant Genetic Resources Institute, Rome Prat D, Leger C, Bojovic S (1992) Genetic diversity among Alnus glutinosa (L.) Gaertn. populations. Acta Oecologica 13:469477 King RA, Ferris C (2000) Chloroplast DNA and nuclear DNA variation in the sympatric alder species, Alnus cordata (Lois.) Duby and A. glutinosa (L.) Gaertn. Biological Journal of the Linnean Society 70:147160 Psota V (1987) Rhizogenesis of stem cuttings in Alnus gluti nosa (L.) Gaertn. and Quercus robur L. species as related to dormancy and plant growth regulators. Acta Universitatis Agriculturae, Facultas Agronomica 35:2744 Krstinič A (1994) Genetics of black alder (Alnus glutinosa (L.) Gaertn.). Annales Forestales 19:3372 Krstinič A, Kajba D (1991) Possibilities of genetic gain for vig orous growth of black alder (Alnus glutinosa (L.) Gaertn) by clonal seed orchard. Sum. list 69:261271 Kruger H (1982) Vegetative vermehrung von Nadel und Laub hölzen. Allgemeine Forstzeitschrift 910:243244 Lall S, Mandegaran Z, Roberts AV (2005) Shoot multiplication in cultures of mature Alnus glutinosa. Plant Cell Tissue and Organ Culture 83:347350 Martin B, Guillot J (1982) Quelques essais de bouturage de l’aulne. Revue Forestière Francaise 34:381391 McVean DN (1953) Alnus glutinosa (L.) Gaertn. Journal of Ecology 43:447466 Périnet P, Tremblay FM (1987) Commercial micropropagation of five Alnus species. New Forests 3:225230 Simon L, Stain A, Côte S, Lalonde M (1985) Performance of in vitro propagated Alnus glutinosa (L.) Gaertn. clones inocula ted with Frankiae. Plant and Soil 87:125133 Steiner W, Gregorius HR (1999) Incompatibility and pollen competition in Alnus glutinosa: evidence from pollination ex periments. Genetica 105:259271 Suszka B, Muller C, BonnetMasimbert M (1994) Graines des feuillus forestiers, de la recolte au semis. INRA, Paris Vergnaud L, Chaboud A, Rougier M (1987) Preliminary analy sis of root exudates of in vitromicropropagated Alnus gluti nosa clones. Physiologia Plantarum 70:319326 Weisgerber H (1974) First results of progeny test with Alnus glutinosa Gaertn. after controlled pollination. In: Proceedings of the Join IUFOR Meeting, SO2.04.13. Session VI, Stockholm Alnus glutinosa 26 Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Albania, Greece (incl. Kriti), Cyprus, Turkey, Lebanon, Tunisia, Algeria, Morocco This typical Mediterranean species prefers rather cool soil and does not weather prolonged intense cold too well. In the lower and warmer areas of its distribution Diagnostic traits Arbutus unedo is a perennial shrub or small tree up to 4 – 7 m height, with alternate, lanceolate leaves. In the eastern area of its range of distribution it sometimes shares territory with Arbutus andrachne, from which it differs in that its bark is fissured, brownish in colour Reproductive biology Sex expression ■ hermaphroditism Arbutus unedo L. EN: strawberry tree EL: κουμαριά ES: madroño FR: arbousier IT: corbezzolo PT: medronheiro Flowering white flowers, clustered in panicles ■ from October to December ■ Pollination ■ range it can be found in shaded spots. It is more abun dant on siliceous soils, but can also be found on cal careous substrates. It resprouts well from the stump after fire or cutting. The strawberry tree grows in Quercus and Pinus forests or among high shrubs together with other typical species of the Mediterranean maquis. Although not specifically a waterside species, its need for somewhat cool soils and its interaction with animals make it worth considering for use in areas of transition be tween riparian and zonal vegetation. and peels off in small flakes, its young twigs are often glandulosesetose and it blooms in the autumn. In con trast, the bark of A. andrachne is brilliant orangered in colour, smooth and peels off in papery sheets, and it blooms in the spring. entomophilous Fruiting Ripening ■ ■ globose red or orange berry, glandulose ■ 2025 mm from October to December ■ dispersal by frugivorous vertebrates 27 Arbutus unedo Ericaceae Variation and Hybridisation Hybridisation of A. unedo and A. andrachne (A. × an drachnoides Lint.) can often occur in areas where both species coexist. The result is a fertile hybrid exhibiting the brightlycoloured bark of A. andrachne and some glandulose hairs on its young twigs. Also recognised is Arbutus × androsterilis Salas, Acebes & Arco, a hybrid of A. unedo and A. canariensis (Salas Pascual et al., 1993) resulting from artificial sympatry. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from October to December ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 614 g ■ purity: 7097 % The fruit production of strawberry trees varies greatly from one year to the next (Herrera, 1988), since seed 23 g quantity and quality are affected by the intensity and du ration of summer drought periods (Chiarucci et al., 1993). Germination under controlled conditions Pregermination treatments ■ prechilling (412 weeks) Conditions ■ T: 4 ºC MC: 48 % ■ airtight container ■ 15 to 20 ºC Germination Viability ■ 8099 % Strawberry tree seeds have no problem in germinating, but emergence is accelerated and made more homo geneous by prechilling. Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Nursery practice ■ ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Strawberry tree seedlings are very sensitive; care must be taken to avoid the effects of frost and excessive heat. Emergence ■ the first spring, complete within 34 weeks Arbutus unedo 28 Type of cutting ■ semihardwood Position along the shoot terminal Number of internodes Size 2 The results obtained through vegetative propagation of strawberry trees are very irregular. It has not been pos sible to obtain rooting percentages higher than 50% (Crobeddu and Pignatti, 2005; Pignatti and Crobeddu, 2005). According to Pignatti and Crobeddu (2005), it is necessary to use material obtained from young parent plants which have been repeatedly pruned to stimulate vigorous sprouting. If this type of material is not used, References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Villar L (1996) Arbutus L. In: Castroviejo S. et al. (eds). Flora Ibérica. Vol 4. CSIC, Madrid Webb DA (1972) Arbutus L. In: Tutin TG et al. (eds). Flora Eu ropaea. Vol 3. Cambridge University Press, Cambridge Specific references Cervelli C (2005) Le specie arbustive della macchia medite rranea. Un patrimonio a valorizzare. Collana Sicilia Foreste 26:39154 Chiarucci A, Pacini E, Loppi S (1993) Influence of temperature and rainfall on fruit and seed production of Arbutus unedo L. Botanical Journal of the Linnean Society 111:7182 Collecting time june Auxin concentration 1% the rooting probability seems to be nil. The best time to harvest cuttings is at the end of the growth period. After this time, the rootforming capacity diminishes by 1020% (Cervelli, 2005). The strawberry tree has been successfully propagated by in vitro culture (Giordani et al., 2005; Mereti et al., 2002; Morini y Fiaschi, 2000; Rodrigues et al., 2001). Crobeddu S, Pignatti G (2005) Propagazione per talea di specie mediterranee. Prove di substrato. Sherwood Foreste ed Alberi Oggi 114:2731 Giordani E, Benelli C, Perria R, Bellini E (2005) In vitro germi nation of strawberry tree (Arbutus unedo L.) genotypes: es tablishment, proliferation, rooting and callus induction. Advances in Horticultural Science 19:216220 Herrera CM (1998) Longterm dynamics of Mediterranean fru givorous birds and fleshy fruits: a 12yr study. Ecological Monographs 68:511538 Mereti M, Grigoriadou K, Nanos GD (2002) Micropropagation of the strawberry tree, Arbutus unedo L. Scientia Horticulturae 93:143148 Morini S, Fiaschi G (2000) In vitro propagation of strawberry tree. Agricoltura Mediterranea 130:240246 Pignatti G, Crobeddu S (2005) Effects of rejuvenation on cut ting propagation of Mediterranean shrub species. Foresta 2:290295 (online URL http://www.sisef.it/) Rodrigues AP, Sergio.PM, Teixeira MR, Pais MS (2001) In vitro break of dormancy of axillary buds from woody species (Persea indica and Arbutus unedo) by sectioning with a laser beam. Plant Science 161:173178 Salas Pascual M, Aceves Ginovés JR, del Arco Aguilar M (1993) Arbutus x androsterilis, a new interespecific hybrid between A. canariensis and A. unedo from the Canary Islands. Taxon 42:789792 29 Arbutus unedo Vegetative propagation Celtis australis L. Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Cyprus, Turkey, Syria, Lebanon, Tunisia, Algeria, Morocco The European hackberry has been grown widely in the Mediterranean basin since ancient times because of its many uses, making it difficult to establish the precise limits of its natural distribution range. It is often asso Diagnostic traits This species is a deciduous tree that can grow to a height of 30 m. Its bark is smooth and greyish coloured. Its leaves are sharply serrate, rounded or cor date at the base and usually two to three times as long as broad. The fruits are globose, with a strongly retic ulaterugose endocarp. It differs from Celtis tournefortii, which is distributed throughout the south of Europe from Sicily to the EN: European hackberry, European nettletree EL: μελικουκιά ES: almez FR: micocoulier IT: bagolaro PT: lódãobastardo Ulmaceae ciated with farming and stockbreeding and may be found near rural buildings, alongside ditches and on the edges of fields. Spontaneous distribution occurs in the form of scat tered individuals, in small pure stands or mixed with other broadleaves species. The hackberry is found in forests and ravines and on rocky, shady slopes, in semi arid and subhumid Mediterranean environments. It prefers cool, loose, rocky soils and is indifferent to sub strate. It resprouts from the stump and the root after cutting or fire. Crimea, in that the latter is a bush or small tree not usually exceeding 6 m in height, with leaves that are less than twice as long as broad, and its endocarp has four ridges. Morphological differences as regards Celtis caucasica, which is found in Bulgaria, Yugoslavia and western Asia, are less obvious, since C. caucasica also grows into a tree, although its leaves are cuneate at the base and its fruit is yellowish brown when ripe. Celtis australis 30 Reproductive biology Sex expression ■ andromonoecy Flowering Pollination flowers small and inconspicuous, generally solitary ■ from March to May ■ ■ anemophilous Fruiting Ripening ■ ■ brownishblack, spherical drupe ■ 812 mm from October, may remain until late winter on the tree ■ dispersal by frugivorous vertebrates Variation and Hybridisation There is no information on intraspecific variation and hybridisation for this taxon. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from November to winter ■ climbing, or using longhandled tools, or beating branches sequence for fleshy fruits ■ seed weight / kg fruit: 320400 g ■ purity: 95100 % 100260 g Germination under controlled conditions Pregermination treatments ■ prechilling (8–12 weeks) Conditions ■ 20 / 10 ºC T: 4 ºC MC: 48 % ■ airtight container ■ Germination Viability ■ 4096 % European hackberry has dormancy that requires prechilling. Sowing season ■ autumn, without treatment, or spring, with treatment Nursery practice bareroot: circumference up to 46 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ Emergence ■ the first spring 31 Celtis australis Nursery production Vegetative propagation Type of cutting ■ ■ hardwood semihardwood Position along the shoot basal or middle basal or middle Number of internodes Size 20 cm 10 cm It is advisable to perform rejuvenation pruning on the parent plants (Butola and Uniyal, 2005; Puri and Shamet, 1988). Treatment with a high concentration of auxins is indispensable to guarantee results of above References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Navarro C, Castroviejo S (1993) Celtis L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Collecting time January to March July Auxin concentration 0.5 1% 0.5 1% 50% (Shamet and Naveen, 2005). However, according to trials carried out by Puri and Shamet (1988), the concentration of indolebutyric acid could be reduced to 0.01% if the treatment time is increased to 24 hours. Tutin TG (1993) Celtis L. In: Tutin TG et al. (eds). Flora Euro paea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Specific references Butola BS, Uniyal AK (2005) Rooting response of branch cut tings of Celtis australis L. to hormonal application. Forests, Trees and Livelihoods 15:307310 Puri S, Shamet GS (1988) Rooting of stem cuttings of some social forestry species. International Tree Crops Journal 5:6369 Shamet GS, Naveen CR (2005) Study of rooting in stem cut tings of Khirk (Celtis australis Linn.). Indian Journal of Forestry 28:363369 Celtis australis 32 Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia Mediterranean region: France, Italy (incl. Sicilia), Croa tia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Turkey, Syria, Lebanon, Palestine Diagnostic traits C. siliquastrum is a deciduous tree, 5 to 10 m in height, with smooth bark. Its leaves are simple, alter nate, orbicular or reniform, with a rounded apex. Its flowers are pink or purplish and sprout directly from the trunk and branches. C. siliquastrum may be easily Reproductive biology Sex expression ■ hermaphroditism Cercis siliquastrum L. EN: Judas tree, lovetree EL: κουτσουπιά ES: árbol del amor, árbol de Judas FR: arbre de Judée, gainier IT: albero di Giuda, siliquastro PT: olaia, árvore de Judas Flowering pale to deep pink flowers, clustered in racemes that growth directly from the stems and trunk ■ from March to May, before leaf development ■ Pollination ■ ■ Lovetree is normally found on arid slopes or on the banks of rivers, on calcareous substrates, although it also tolerates moderately acid soils. It cannot with stand prolonged periods of cold. confused with many other Cercis varieties that are used for ornamental purposes. Two of these are C. canadensis, which has leaves with a pointed apex, and C. chinensis, whose leaves are deeply acuminate at the base. entomophilous selfcompatible Analysis of storage proteins in seed sets of individual trees indicates that the love tree is almost completely Fruiting Ripening ■ ■ reddish to dark brown legume ■ 60100 mm long in July, remaining many months on the tree ■ dispersal by gravity autogamous, with less than 5% of crossfertilisation (González and HenriquesGil, 1994). 33 Cercis siliquastrum Fabaceae Variation and Hybridisation The subspecies C. siliquastrum subsp. hebecarpa (Bornm.) Yalt., distributed in Asia Minor and Iran, has nonglabrous calyces, pedicels and legumes. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from late summer gathering by hand or beating branches sequence for dehiscent fruits ■ seed weight / kg fruit: 300450 g ■ purity: 9598 % Legumes can be collected any time after they turn dark and the seeds turn brown. Although they remain closed on the tree during most of the winter, early collection 2035 g is prudent to minimize seed losses that might occur from insect infestation. Germination under controlled conditions Pregermination treatments mechanical scarification mechanical scarification + prechilling (412 weeks) ■ soaking in boiling water (1 minute) ■ soaking in water at 80 ºC and allowing to cool for 24 h ■ scarification with concentrated sulphuric acid (3060 minutes) ■ Conditions ■ ■ Nursery production Sowing season ■ spring, with treatment Germination Viability 30 / 20 ºC Love tree seeds experience dormancy due to the en dosperm and to their impermeable coat (Riggio Bevilacqua et al., 1985, 1988) and require scarification and prechilling in order to germinate. The duration of acid scarification should be determined by means of tests for each seed lot. The application of gibberellic ■ 7090 % acid can break dormancy in previously soaked seeds, but stratification for 16 weeks at 4 ºC is much more efficient (Gebre and Karam, 2004). The use of acid may also have a negative effect on the subsequent devel opment of the seedling (Rascio et al., 1998). Nursery practice Cercis siliquastrum 34 bareroot; circumference up to 46 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ T: 4 ºC MC: 48 % ■ airtight container ■ Emergence ■ the same spring, 24 weeks after sowing Type of cutting ■ semihardwood Position along the shoot terminal Number of internodes Size 23 Lovetree is not easily reproduced from cuttings. Consi derable variation in rooting ability depending on the part of the shoot from which the cutting is taken and the collection time has been observed (Karam and Gebre, 2004). References General references Ball PW (1968) Cercis L. In: Tutin TG et al. (eds). Flora Euro paea. Vol 2. Cambridge University Press, Cambridge Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid Chamberlain DF, Yaltirik F (1970) Cercis L. In: Davis PH (ed). Flora of Turkey and the Eastern Aegean Islands. Vol 3. Univer sity Press, Edinburgh Mac Cárthaigh D, Spethmann (eds) W (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Bignami C (1984) Prove di micropropagazione di Cercis sili quastrum L.. Informatore Agrario 40:103105 Collecting time summer (July) Auxin concentration 1% Micropropagation of lovetree has been tried with some success using axillary buds (Bignami, 1984). Gebre GH, Karam NS (2004) Germination of Cercis siliquas trum seeds in response to gibberellic acid and stratification. Seed Science and Technology 32:255260 González C, HenriquesGil N (1994) Genetics of seed storage proteins in the love tree Cercis siliquastrum L. (Fabaceae). The oretical and Applied Genetics 89:895899 Karam NS, Gebre GH (2004) Rotting of Cercis siliquastrum cuttings influenced by cutting position on the branch and in dolebutyric acid. Journal of Horticultural Science and Biotechnology 79:792796 Rascio N, Mariani P, Dalla Vecchia F, La Rocca N, Profumo P Gastaldo P (1998) Effects of seed chilling or GA3 supply on dormancy breaking and plantlet growth in Cercis siliquastrum L. Plant Growth Regulation 25:53–61 Riggio Bevilacqua L, Roti Michelozzi G, Serrato Valenti G (1985) Barriers to water penetration in Cercis siliquastrum seeds. Seed Science and Technology 13:175182 Riggio Bevilacqua L, Profumo P, Gastaldo P, Barella P (1988) Cytochemical study on the dormancyimposing endosperm of Cercis siliquastrum. Annals of Botany 61:561565 35 Cercis siliquastrum Vegetative propagation Ranunculaceae Clematis flammula L. Clematis vitalba L. Clematis vitalba L. Clematis flammula L. EN: clematis, traveller’sjoy EL: κληματίς ES: clemátide FR: clématite IT: clematide PT: clematis Distribution and Ecology C. vitalba: General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Syria, Lebanon, Algeria C. flammula: General distribution: Southwestern and Southeastern Europe, Caucasus, Western Asia, Northern Africa Mediterranean countries: Portugal, Spain (incl. Balea res), France (incl. Corse), Italy (incl. Sardegna, Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Turkey, Cyprus, Syria, Lebanon, Is rael, Libya, Tunisia, Algeria, Morocco C. vitalba. C. flammula 36 Clematis vitalba and C. flammula may be among the climbers that make up the riparian vegetation. C. vi talba requires greater amounts of moisture and is com mon in broadleaved forests and deciduous spiny thickets in Eurosiberian environments, although it is also found in shady and cool areas in the Mediter ranean region. C. flammula likes warmer weather and is restricted to the Mediterranean coast; it is also found in hedges, thickets and forests, on sunny open ground. Diagnostic traits Clematis vitalba and C. flammula are perennial lianas with woody stems, at least in their lower parts. They can be distinguished because the former has 1pinnatisect leaves with ovate, cordateovate or ovallanceolate leaflets, while the leaves of the latter are mostly bipin natisect, sometimes tripinnatisect, with ovate, lanceolate or linear leaflets. The perianth segments in C. flammula are white and glabrous on the inside; in C. vitalba, they are greenish white and pubescent on both sides. Reproductive biology Sex expression ■ hermaphroditism Flowering flowers clustered in paniculiform cymes ■ from May to August, occasionally later ■ In addition to these two species, other climbing Clema tis varieties are found less frequently in the Mediter ranean region: C. viticella L., with purplish flowers, and C. campaniflora Brot., which is limited to the centre and the west of the Iberian Peninsula and has solitary or two to four clustered flowers and bracteoles that are welded together to form an involucre below the flower. Pollination ■ entomophilous Fruiting Ripening ■ ■ achene with a persistent feathery plume ■ 23 mm (plume length: up to 3.5 cm C. flammula; up to 5.5 cm C. vitalba) from September to November ■ dispersal by wind Variation and Hybridisation There is no information on intraspecific variation and hybridisation for these taxa. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from October to December ■ gathering by hand friction for feathery style removal ■ purity: 99100 % ■ 57 g C. flammula (achenes) 13 g C. vitalba (achenes) T: 4 ºC MC: 48 % ■ airtight container ■ 37 C. vitalba. C. flammula Seeds are not usually extracted from the achenes. Germination under controlled conditions Pregermination treatments ■ manual removal of seeds from fruits or mechanical scarification + prechilling (8–24 weeks) Conditions ■ 20 / 10 ºC; 20 ºC Clematis seeds have morphophysiological dormancy and prechilling is required for germination. Cold strat ification for 8 to 12 weeks seems to be adequate for the germination of Clematis vitalba seeds (Bungard et Nursery production Sowing season ■ autumn or early spring, without treatment, or spring, with treatment Vegetative propagation Type of cutting ■ semihardwood or softwood Position along the shoot indifferent Germination Viability ■ al., 1997). Prechilling can be replaced by applying al ternating temperatures of 5 ºC for 12 hours and 15 ºC for 12 hours in an incubator (Vinkler et al., 2004). Nursery practice ■ forestpot 300 cm3: 1/0 or 2/0 Number of internodes Size 12 Propagation of the genus Clematis is carried out in summer using shoots that have grown in the spring of the same year. Use of softwood cuttings with a pair of leaves is recommended. Münster (2000) recommends making a cut in the lower 2 cm of the cutting, leaving the cambium visible, to accelerate the formation of roots. One of the leaves may be removed to save space and to avoid fungal infections by the genus Botrytis. Another form of propagation is the socalled ‘Japan ese method’, which also uses cuttings with a node but somewhat longer and more vigorous, since the cuts are made in the internodes immediately above and below 6595 % Emergence ■ in the first spring, may be complete in the following autumn Collecting time summer Auxin concentration without or < 0.5 % the node. In this method, the probability of fungi reaching the buds is much lower than in the conven tional method. However, it has the disadvantages of occupying more space and providing less material from each parent plant (Gunn, 2005). Kreen et al. (2002) rec ommends using perlite as a substrate and rooting in a mist environment. Rooting microcuttings obtained by in vitro propaga tion seems to be more effective than the traditional method using softwood cuttings (Kreen et al., 2002). C. vitalba. C. flammula 38 General references Fernández Carvajal MC (1986) Clematis L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 1. CSIC, Madrid. Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Strid A (1967) Clematis L. In: Stris A, Tan K (eds). Flora Hel lenica. Vol 2. ARG Gantner Verlag KG, Ruggell Tutin TG and Akeroyd JR (1993) Clematis L. In: Tutin TG et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Bungard RA, Daly GT, McNeil DL, Jones AV, Morton JD (1997) Clematis vitalba in a New Zealand native forest remnant: does seed germination explain distribution? New Zealand Journal of Botany 35:525534 Gunn S (2005) Clematis from cuttings. Plantsman 4:8183 Kreen S, Svensson M, Rumpunen K (2002) Rooting of Clema tis microshoots and stem cuttings in different substrates. Sci entia Horticulturae 96:351357 Münster K (2000) Clematis. In: Mac Cárthaigh D, Spethmann W (eds). Krüssmans Gehölzvermehrung. Parey/Blackwell Wis senschaftsverlag, Berlin Vinkler I, Muller C, Gama A (2004) Germination de la Clé matite (Clematis vitalba L.) et perspectives de maîtrese préventive au forêt. Revue Forestière Française 56:275286 39 C. vitalba. C. flammula References Coriaria myrtifolia L. μυρτόφυλλος, κοριάρια η μυρτόφυλλη ES: emborrachacabras, garapalo FR: corroyère, redoul IT: coriaria, sommacco provenzale PT: coriaria Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Northern Africa Mediterranean region: Spain (incl. Baleares), France, Italy, Algeria, Morocco Coriaria myrtifolia is a species that requires moderately moist soils. It is indifferent to the nature of the sub Diagnostic traits This species is a semideciduous bush that reaches a height of 1 to 2 m, with simple, entire, opposite leaves. Reproductive biology Sex expression ■ andromonoecy Flowering greenish flowers, clustered in raceme ■ from March to June ■ Coriariaceae EN: coriaria EL: βυρσοδεψική η Pollination ■ ■ strate and grows in partial shade or under full sunlight. It is found in the Mediterranean region, from the coast to the mountain areas, in riversides, ravines, bramble patches and moist hedges. It has a strong root system that acts in symbiosis with bacteria to fix atmospheric nitrogen, allowing it to vegetate on nutrientpoor soil. Its fruit is very striking, both in shape and colour, but highly toxic to humans. anemophilous selfcompatible Coriaria myrtifolia 40 In spite of the selfcompatibility of the species, cross fertilisation between individuals is enhanced by the fact that male flowers appear before hermaphrodite flowers in each single plant (Thompson et al., 1995). Fruiting Ripening ■ ■ black achene, surrounded by keeled, fleshy pieces, initially red, black when ripe ■ about 4 mm from July to September ■ dispersion by frugivorous vertebrates Thus it would seem that the fruit collected from a sin gle mother plant would tend to result from pollination by different individuals. Variation and Hybridisation Coriaria is the only genus of the Coriariaceae family, which has a conspicuously disjunct world distribution (Yokoyama et al., 2000). C. myrtifolia is the only species that is present in Europe. Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from late summer to early autumn ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 1034 g ■ purity: 99100 % 1113 g Germination under controlled conditions Pregermination treatments ■ mechanical scarification + immersion in a 500 ppm gibberellic acid solution (4 days) + prechilling (4 weeks) Nursery production Sowing season ■ spring, with treatment Conditions ■ ■ Germination Viability 25 / 20 ºC light ■ Nursery practice ■ ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 For mass production in a nursery, pretreatment could be simplified to mechanical scarification and sowing in autumn or in early spring, although emergence could T: 4 ºC MC: 48 % ■ airtight container ■ 8099 % Emergence ■ the same spring, complete within one to two months be slow. Inoculation with nitrogenfixing microor ganisms noticeably improves the development of the plants (Martinez et al., 1997; Cañizo et al., 1978). 41 Coriaria myrtifolia Tolerance to desiccation: ORTHODOX Vegetative propagation Type of cutting ■ semihardwood Position along the shoot basal or middle Number of internodes Size 10 15 cm Vegetative propagation of Coriaria myrtifolia offers better results when using softwood cuttings harvested during vegetative rest (autumnwinter). However, root ing of Coriaria myrtifolia cuttings in autumnwinter must be done in a protected environment, maintaining a temperature of 20 ºC (Melgares de Aguilar et al., References General references Webb DA (1968) Coriaria L. In: Tutin TG et al. (eds). Flora Eu ropaea. Vol 2. Cambridge University Press, Cambridge Specific references Cañizo A, Miguel C, RodríguezBarrueco C (1978) The effect of pH on nodulation and growth of Coriaria myrtifolia L. Plant and Soil 49:195198 MartínezSánchez JJ, Orozco E, Selva M, Gilabert J (1997) Ob tención de planta de Coriaria myrtifolia L. en vivero. Ensayos de inducción a la nodulación en sustrato estéril. Montes 50:4044 Collecting time autumn winter Auxin concentration none or < 0.5 % 2005). If these conditions cannot be met, it is prefer able to harvest the cuttings in early spring, when tem peratures begin to increase. Melgares de Aguilar et al. (2005) obtained 85 % survival rates when cuttings were collected in the spring, compared to 100% for cuttings obtained in the autumn. Melgares de Aguilar J, González D, Navarro A, Bañón S, Gar cía F (2005) Influencia de la estacionalidad en el enraiza miento de esquejes de Coriaria myrtifolia L. V Congresso Ibérico de Ciências Hortícolas ; IV Congresso Iberoamericano de Ciências Hortícolas Vol 1:457461. Asociación Portugesa de Ciencias Hortícolas, Porto Thompson PN, Gornall PN, Gornall FLS RJ (1995) Breeding systems in Coriaria (Coriariaceae). Botanical Journal of the Linnean Society 117:293304 Yokoyama J, Suzuki M, Iwatsuki K, Hasebe M (2000) Molecu lar phylogeny of Coriaria, with special emphasis on the dis junct distribution. Molecular Phylogenetics and Evolution 14:11–19 Coriaria myrtifolia 42 General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, Western Asia Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey Diagnostic traits Cornus sanguinea is a deciduous shrub, 1.5 to 6 m in height, with dark red twigs and opposite, ovate or el liptic, entire leaves. Its flowers, which have dull white or pale yellowishwhite petals, come out after its leaves Reproductive biology ■ hermaphroditism Flowering white flowers, clustered in large corymbiform cymes ■ from April to July, sometimes also in autumn ■ Pollination ■ The common dogwood is a species that requires a cool environment. In the Mediterranean region it thus finds refuge in shady areas, ravines, riverbanks, and humid thorny thickets. In less dry regions it is found on the edges of forests and glades and in deciduous thickets. It needs soils that are relatively rich in nutrients but grows on substrates with different pH levels. It toler ates calcareous materials quite well and grows easily on heavy soils. have grown, in contrast to Cornus mas, a species with yellow or greenish flowers that is found widely in west ern Asia and Europe. entomophilous Fruiting Ripening ■ ■ ■ black globose drupe 58 mm from July to October ■ dispersal by frugivorous vertebrates 43 Cornus sanguinea Distribution and Ecology Sex expression Cornus sanguinea L. EN: common dogwood EL: αγριοκρανιά ES: cornejo FR: cornouiller sanguin IT: corniolo PT: sanguinho legítimo Cornaceae Variation and Hybridisation Two subspecies have been described: C. sanguinea subsp. sanguinea and C. sanguinea subsp. australis. The latter is found in Southeast Europe and Southwest Asia. The difference between these subspecies has to do with the type of indumentum on the back of the leaves, which consists of simple, more or less curly hairs in C. sanguinea, while in C. australis the hairs are navicular and parallel to the nerves. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from August to early autumn ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 172317g ■ purity: 100 % Cornus sanguinea crops vary both interannually and between populations, but in general the fruittoflower ratio is very low, due to the high incidence of fruit abortion throughout the stages of its development (Krüsi and Debussche, 1988). However, in cases of high 3055 g flower mortality (resulting from predation, for exam ple), the proportion of aborted fruit is lower (Guitián et al., 1996). Fruits should be collected as soon as they are ripe, to reduce losses to birds. Germination under controlled conditions Pregermination treatments preheating (8 weeks) + prechilling (812 weeks) ■ scarification with concentrated sulphuric acid (120 minutes) + prechilling (12 weeks) ■ Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Conditions ■ ■ 30 / 20 ºC; 20 / 10 ºC light Nursery practice ■ ■ T: 4 ºC MC: 48 % ■ airtight container ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Germination Viability ■ 8096 % Emergence ■ the first spring, may be completed in the second spring Cornus sanguinea 44 Vegetative propagation Type of cutting ■ hardwood Position along the shoot indifferent Number of internodes Size 20 cm Vegetative propagation of Cornus sanguinea is readily achieved with hardwood material collected in the win ter. It is not necessary to apply hormones, although their use makes the rooting time uniform. References General references Ball PW (1968) Cornus L. In: Tutin TG et al. (eds). Flora Euro paea. Vol 2. Cambridge University Press, Cambridge Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Nieto Feliner G (1997) Cornus L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 8. CSIC, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Collecting time winter Auxin concentration none Experiments have been conducted on in vitro propaga tion of other species of the genus Cornus (Edson et al., 1994; Kaveriappa et al., 1997). Specific references Edson JL, Wenny DL, LeegeBrusven A (1994) Micropropaga tion of Pacific dogwood. HortScience 29:13551356 Guitián J, Guitián P, Navarro L (1996) Fruit set, fruit reduc tion, and the fruiting strategy of Cornus sanguinea (Cor naceae). American Journal of Botany 83:744748 Kaveriappa KM, Phillips LM, Trigiano RN (1997) Micropropa gation of flowering dogwood (Cornus florida) from seedlings. Plant Cell Reports 16:485489 Krüsi BO, Debussche M (1988) The fate of flowers and fruits of Cornus sanguinea L. in three contrasting Mediterranean ha bitats. Oecologia 74:592599 45 Cornus sanguinea Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Crataegus monogyna Jacq. Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, Western Asia, Northern Africa Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Diagnostic traits The hawthorn is a small prickly tree, 5 (10) m in height, with thorns 7 to 20 mm in length. Its leaves exhibit large variations in shape and size within the same in dividual, from deeplylobed to entire blade. The genus Crataegus, like other species of Rosaceae, is of great taxonomic complexity. C. monogyna can be distinguished from the other species of the genus that are found in Mediterranean Europe by EN: hawthorn, white thorn EL: τρικουκκιά, μουρτζιά ES: espino albar, majuelo FR: aubépine, noble épine IT: biancospino, marucca bianca PT: pilriteiro, espinheiroalvar Rosaceae Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel, Tunisia, Algeria, Morocco This species has a broad ecological range. It is found at the edges and in glades of deciduous forests and in deciduous thorny thickets. In more arid regions, it is limited to riparian zones and shady areas. the shape of its leaves or the pilosity of its different structures. Lobes that are entire or have a few acute teeth and entire stipules differentiate it from C. laevi gata, whose leaves have serrulate lobes and serrate stip ules. The twigs, leaves, pedicels and receptacles of C. heldreichii, C. azarolus and C. pycnoloba, species with limited distribution in the eastern Mediterranean region, are tomentose, lanate or sericeous, whereas in C. monog yna they are glabrous or have straight, patent hairs. Crataegus monogyna 46 Reproductive biology Sex expression ■ hermaphroditism Flowering white or pale pink flowers, clustered in corymbs, 4 to 11 flowers per inflorescence ■ from March to June ■ Pollination ■ ■ entomophilous selfcompatible Variation and Hybridisation The complexity of the genus Crataegus is a result of polyploidy (Talent and Dickinson, 2005), hybridisation, introgression and apomixis. Crataegus monogyna in cludes a complex, widely varied number of plants. Nu merous subspecies or varieties have been determined by different authors on the basis of qualitative or quanti tative traits relating to leaves, flowers or fruits. Natural hybrids of C. monogyna and C. azarolus or C. laevigata have been described. The introgression between C. monogyna and C. laevigata seems to have been con firmed by molecular techniques (Fineschi et al., 2005). Genetic diversity between and within populations, de termined by molecular techniques, would seem to be Fruiting Ripening ■ ■ ■ red pome 610 mm from August to November ■ dispersal by frugivorous vertebrates low and to lack spatial structuring, possibly as a result of extensive fruit dispersal by animals (Fineschi et al., 2005). According to the results of these determinations, material from individuals of distant populations could potentially be collected and mixed, although it is ad visable to be cautious and to keep to collection units located within the limits of the same region of prove nance, seed zone or ecological unit. Such conservative practice is supported by the results obtained when using material of different origins in a series of refor estation projects under varying ecological conditions, where local populations have been shown to adapt bet ter to the climate and to be more resistant to disease (Jones et al., 2001). Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from late summer to early autumn ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 150230 g ■ purity: 99100 % C. monogyna seems to exhibit a marked tendency to fruit abortion, especially at the beginning of the fruit development cycle, although the incidence varies be tween individuals (Guitián et al., 1992). Material col lection should not focus too heavily on the most productive plants, but must be well spread out among the entire tree population. 55180 g T: 4 ºC (23 years) MC: 48 % ■ airtight container ■ Collecting at the end of the summer, when the fruit is reddish but has not yet ripened completely, can shorten seed germination time. 47 Crataegus monogyna Tolerance to desiccation: ORTHODOX Germination under controlled conditions Pregermination treatments preheating (416 weeks) + prechilling (1236 weeks) ■ mechanical scarification + prechilling (48 or more weeks) ■ scarification with concentrate sulfuric acid (30120 minutes) + prechilling (48 or more weeks) ■ mechanical or acid scarification + preheating (412 weeks) + prechilling (1220 weeks) ■ Conditions ■ Germination Viability 30 / 20 ºC ■ 70100 % Hawthorn seeds display deep embryo dormancy and a thickened endocarp and require both scarification and prechilling to germinate. Nursery production Sowing season ■ late summer, without treatment, seeds from not completely ripened fruits immediately after collecting these, or spring with treatment Vegetative propagation Type of cutting hardwood semihardwood ■ root ■ ■ Position along the shoot basal or middle basal or middle Nursery practice Emergence forestpot 300 cm3: 1/0 ■ container 3.5 l: 1/1 79 months after late summer sowing, may be completed in the following spring ■ 2 months after spring sowing, may be completed in the second spring ■ Number of internodes Size 15 cm 10 cm 58 cm Crataegus monogyna 48 Vegetative propagation of Crataegus is not common practice. However, it is possible to use this technique with acceptable results. In order to obtain suitable hardwood cuttings, parent plants must have been sub jected to aggressive pruning to achieve rejuvenation. Crobeddu and Pignati (2005) obtained 76% rooting success using semihardwood cuttings harvested in July from rejuvenated parent plants and maintained in a mist environment at a basal temperature above 20 ºC. It is also possible to propagate this species with some ■ Collecting time winter summer winter Auxin concentration 1% 0.5 % none success from root cuttings. Göttsche (1978) obtained a 30% survival rate with this method, planting cuttings vertically in a mixture of peat and sand (1:1), that is to say, leaving part of the root cutting above the sub strate. In vitro propagation of Crataegus monogyna is possible and offers better results than conventional vegetative propagation. Wawrosch et al. (2007) used axillary buds collected in winter as cuttings. General references Amaral Franco J do (1968) Crataegus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Fineschi S, Salvini D, Turchini D, Pastorelli R, Vendramin GG (2005) Crataegus monogyna Jacq. and C. laevigata (Poir.) DC. (Rosaceae, Maloideae) display low level of genetic diversity assessed by chloroplast markers. Plants Systematic and Evo lution 250:187196 Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Göttsche D (1978) Vermehrung einheimischer Straucharten durch Wurzelschnittlinge. Forstarchiv 49:3336 Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Guitián J, Sánchez JM, Guitián P (1992) Niveles de fructifica ción en Crataegus monogyna Jacq., Prunus mahaleb L. y Pru nus spinosa L. (Rosaceae). Anales del Jardín Botánico de Madrid 50:239245 Muñoz Garmendia F, Navarro C, Aedo C (1998) Crataegus L. In: Muñoz Garmendia F, Navarro C (eds). Flora Ibérica. Vol 6. CSIC, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Crobeddu S, Pignatti G (2005) Propagazione per talea di specie mediterranee prove di substrato. Sherwood Foreste ed Alberi Oggi 114:2731 Jones AT, Hayes MJ, Sackville Hamilton NR (2001) The effect of provenance on the performance of Crataegus monogyna in hedges. Journal of Applied Ecology 38:952–962 Talent N, Dickinson TA (2005) Polyploidy in Crataegus and Mespilus (Rosaceae, Maloideae): evolutionary inferences from flow cytometry of nuclear DNA amounts. Canadian Journal of Botany 83:12681304 Wawrosch C, Prinz S, Soleiman Y, Kopp B (2007) Clonal prop agation of Crataegus monogyna Jacq. (Lindm.). Planta Medica 73:1013 49 Crataegus monogyna References Dorycnium rectum (L.) Ser. Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Albania, Greece (incl. Kriti), Turkey, Syria, Lebanon, Israel, Tunisia, Algeria, Morocco Diagnostic traits This is a herbaceous perennial plant, sometimes woody at the base, not spiny, that can reach a height of 30 to 200 cm. Leaves are composed of five leaflets, the basal two are ovate, acute and the other three are obovatespatulate, mucronate. Other species of the genus that are widely distributed in the Mediter Reproductive biology Sex expression ■ hermaphroditism Flowering whitepink flowers clustered in glomerules, 18 to 40 flowers in each ■ from May to September ■ Leguminosae EN: greater badassi EL: μελιγκάρια ES: unciana FR: dorycnie dressée IT: trifoglino palustre PT: ervamatapulgas Pollination ■ Dorycnium rectum grows in grasslands and in rush beds on the banks of watercourses in the Mediterran ian region. It prefers alkaline reaction soils. It fixes atmospheric nitrogen. ranean region (D. pentaphyllum, D. hirsutum and D. gracile) are found in inland or coastal bush and pas ture land. Morphologically, D. rectum can be identified because its leaves have a rachis which is at least 3.5 mm long, while in the three other species the rachis is smaller or absent. entomophilous Fruiting Ripening ■ ■ purple or brownish purple legume, more or less cylindrical ■ 1020 mm long from July to September ■ dispersal by explosion Dorycnium rectum 50 Variation and Hybridisation There is no information on intraspecific variation and hybridisation for this taxon. Seed propagation No information about seed production has been found for this species. As a general guideline, data relating to Dorycnium hirsutum are provided; the seeds of the lat ter are larger in size, so the seeds of D. rectum should be somewhat lighter. Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from July to August gathering by hand sequence for dehis cent fruits ■ seed weight / kg fruit: 163 445 g (D. hirsutum) ■ purity: 8599 % 46 g (D. hirsutum) Germination under controlled conditions Pregermination treatments ■ scarification with concentrated sulphuric acid (1520 minutes) Nursery production Sowing season ■ spring, with treatment Vegetative propagation Type of cutting ■ semihardwood Position along the shoot terminal Conditions ■ Germination Viability 20 ºC ■ Nursery practice ■ forestpot 300 cm3: 1/0 or 2/0 Number of internodes Size 10 cm Results obtained by Frangi and Nicola (2004) using Do rycnium hirsutum cuttings suggest that the best time of the year for collecting material is the spring, in the month of April. Alegre et al. (1998) achieved their best results with D. pentaphyllum and D hirsutum cuttings T: 4 ºC MC: 48 % ■ airtight container ■ 8098 % (D. hirsutum) Emergence ■ the same spring Collecting time april Auxin concentration 0.5 1 % taken from the apex of stems and treated with hor mones. These authors recommend protecting the ma terial from the low night temperatures that can occur in the spring. 51 Dorycnium rectum Tolerance to desiccation: ORTHODOX References General references Ball PW (1968) Dorycnium Miller. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Díaz Lifante Z (2000) Dorycnium Mill. In: Talavera S et al. (eds). Flora Ibérica. Vol 7(II). CISC, Madrid Specific references Alegre J, Toledo JL, Martinez A, Mora O, Andres EF (1998) Rooting ability of Dorycnium spp. under different conditions. Scientia Horticulturae 76:123129 Frangi P, Nicola S (2004) Studio della propagazione per talea di specie mediterranee di interesse ornamentale. Italus Hortus 11:191193 Dorycnium rectum 52 Distribution and Ecology General distribution: Southwestern Europe The tamujo growths in watercourses and dry ravines, frequently associated with Nerium oleander. This species prefers welldrained acid soils. Mediterranean region: Portugal, Spain Diagnostic traits Flueggea tinctoria is a spiny deciduous shrub that grows to 2 m, with many branches rising from the base; the young branches are dark reddish. Leaves are alter Reproductive biology Sex expression ■ dioecy Flueggea tinctoria (L.) G.L. Webster EN: EL: ES: tamujo FR: IT: PT: tamuxo Euphorbiaceae Flowering greenish, solitary or fasciculated flowers; male patent/erect; female pendulous ■ from January to April ■ Pollination ■ nate, simple, obovate and glabrous, with a blunt or emarginate apex. anemophilous Fruiting Ripening ■ ■ ■ threelobed capsule 3.54 mm ■ from May to June dispersal by gravity Variation and Hybridisation 53 Flueggea tinctoria There is no information on intraspecific variation and hybridisation for this taxon. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from May to June gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 54 g ■ purity: 98 % ■ Germination under controlled conditions Pregermination treatments ■ no treatments required Nursery production Sowing season ■ autumn or spring ■ ■ hardwood Position along the shoot indifferent Germination Viability 20 ºC ■ Nursery practice ■ Vegetative propagation Type of cutting Conditions ■ Number of internodes Size References General references Benedí C (1997) Flueggea Willd. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 8. CSIC, Madrid 95 % Emergence forestpot 300 cm3: 1/0 container 3.5 l: 1/1 20 cm T: 4 ºC MC: 48 % ■ airtight container 4g ■ 2 to 3 weeks after sowing Collecting time winter Auxin concentration none Gálvez A, Navarro RM (2001) Manual para la identificación y reproducción de semillas de especies vegetales autóctonas de Andalucía. Vol II. Consejería de Medio Ambiente, Junta de Andalucía, Sevilla Flueggea tinctoria 54 General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern and Middle Asia, Siberia, China, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy, Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Tunisia, Algeria, Morocco Diagnostic traits Frangula alnus is a deciduous shrub or small tree with ovaloblong, pointed leaves. Its height of 4 to 5 m dis tinguishes it from Frangula rupestris (Scop.) Schur., an Reproductive biology ■ hermaphroditism Flowering whitegreenish flowers, clustered in cymes ■ from March to July ■ Pollination ■ ■ This species requires cool and damp soils, preferably acidic, although it can also grow on calcareous sub strates. It is found scattered through humid forests, along riversides and in shady ravines in Eurosiberian environments and reaches the Mediterranean region in riparian areas where conditions are moist enough. endemic bush of the eastern Mediterranean region that grows to only 80 cm in height. entomophilous selfincompatible Although frugivorous birds are the principal seed dis persers for Alnus glutinosa, downstream dispersion by water becomes predominant in the Mediterranean Re Fruiting Ripening ■ ■ dark red globose drupe ■ about 7 mm from June to October ■ dispersal by frugivorous vertebrates gion, where riparian zones offer a suitable habitat (Hampe, 2004). 55 Frangula alnus Distribution and Ecology Sex expression Frangula alnus Mill. EN: alder buckthorn EL: βουρβουλιά ES: arraclán FR: bourdaine IT: frangola PT: sanguinhodaágua Rhamnaceae Variation and Hybridisation Of the several subspecies of Frangula alnus that have been described, two are located in Mediterranean countries. F. alnus subsp. baetica (Reverchon & Wilk) Rivas Goday ex Devesa, which is limited to the south of Spain and the north of Morocco, is bigger than the type subspecies and has large leaves (514 x 25.5 cm). The other, F. alnus subsp. pontica (Boiss.) Davis & Yalt., is a shrub or small tree that is endemic to Anatolia and has oblonglanceolate leaves and glabrous twigs instead of the obovateelliptic leaves and pubescent twigs of the type subspecies. Studies using molecular techniques (Hampe et al., 2003) reveal extensive genetic differentiation through out the distribution range of the species, which in cludes three lineages – Iberia, Anatolia and temperate Europe – as a result of its evolutionary history. In mar ginal Mediterranean populations, a high degree of interpopulation genetic differentiation has been es timated due to limited gene flow between populations in these areas, even when close to each other, although intrapopulation variation is low. This pattern of genetic variation makes extreme caution advisable when mov ing reproductive materials of this species; whenever possible, local populations should be used, especially if restoration is to take place in areas where endemic subspecies grow. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from August to November ■ gathering by hand or using longhandled tools sequence for fleshy fruits ■ seed weight / kg fruit: 90150 g ■ purity: 98100 % In the Mediterranean region, where only small popula tions or more or less isolated individuals are to be found, fruit production is scarce due both to limited pollen (Medan, 1994; Hampe 2005) and to climatic factors – especially drought – which lead to a signifi cant degree of interannual crop variation (Hampe 2005). These aspects should be borne in mind when Germination under controlled conditions Pregermination treatments ■ prechilling (8 weeks) Conditions ■ ■ 30 / 20 ºC light 1627 g T: 4 ºC MC: 48 % ■ airtight container ■ planning to collect and produce reproductive material of this species. Fruits should be collected about two weeks before they have ripened completely, in order to avoid predation by birds. Germination Viability ■ 7094 % Frangula alnus 56 Sowing season ■ autumn, without treatment, or spring, with treatment Nursery practice bareroot: 50 g/m2; circumfe rence up to 46 cm or total height up to 80100 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ According to Gálvez and Navarro (2001), the seeds of F. alnus subsp. baetica do not require cold stratifica Vegetative propagation Type of cutting ■ semihardwood Position along the shoot basal or middle 2 3 / 5 10 cm References ■ the first spring tion; they can be sowed directly and germinate in the same spring they are seeded. Number of internodes Size Cuttings may be obtained all along the set if young mother plants are used, although those from the basal and middle parts form stronger roots. When using cut tings collected from adult material, the regenerative capacity of terminal cuttings is considerably reduced (Graves, 2002). Treatment with 0.3 0.8% indolbutyric acid powder noticeably improves the results. Rooting in vermiculite in a mist environment is recommended (Sharma and Graves, 2005). Some references describe Emergence Collecting time summer Auxin concentration 0.5 % propagation using hardwood cuttings in other species of the Rhamnaceae family, using material collected in winter from the basal or middle part of the stem and treated with hormones (Bañón et al., 2003; Dirr and Heuser, 2006). Frangula alnus has been successfully reproduced in vitro, using axillary buds (Bignami 1983) and excised embryos (Kovacevic and Grubisic, 2005). General references Specific references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Bañón S, Martínez JJ, Fernández JA, Ochoa J, González A (2003) Effect of indolebutyric acid and paclobutrazol on the rooting of Rhamnus alaternus stem cuttings. Acta Horticul turae 614:263267 Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Muñoz JM (1987) Frangula. In: Valdés B, Talavera S, Fernán dezGaliano E (eds). Flora Vascular de Andalucía Occidental. Vol 2. Ketres Editora SA, Barcelona. Tutin TG (1968) Frangula Miller. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Yaltirik F (1967) Frangula Miller. In: Davis PH (ed). Flora of Turkey and the Eastern Aegean Islands. Vol 2. University Press, Edinburg Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Bignami C (1983) In vitro propagation of Rhamnus frangula L.. Gartenbauwissenschaft 48:272274 Dirr MA, Heuser CW (2006) The Reference Manual of Woody Plant Propagation: From Seed to Tissue Culture. A Practical Working Guide to the Propagation of over 1100 Species, 2nd ed. Varsity Pr. Inc, Athens Gálvez A, Navarro RM (2001) Manual para la identificación y reproducción de semillas de especies vegetales autóctonas de Andalucía. Vol II. Consejería de Medio Ambiente, Junta de An dalucía, Sevilla 57 Frangula alnus Nursery production Graves WR (2002) IBA, juvenility, and position on ortets in fluence propagation of Carolina buckthorn from softwood cuttings. Journal of Environmental Horticulture 20:5761 Hampe A (2004) Extensive hydrochory uncouples spatiotem poral patterns of seedfall and seedling recruitmente in a “bird dispersed” riparian tree. Journal of Ecology 92:797807 Hampe A (2005) Fecundity limits in Frangula alnus (Rham naceae) relict populations at the species’ southern range mar gin. Oecologia 143:377386 Hampe A, Arroyo P, Jordano P, Petit RJ (2003) Rangewide phy logegraphy of a birddispersed Eurasian shrub: contrasting Mediterranean and temperate glacial refugia. Molecular Ecology 12:34153426 Kovacevic N, Grubisic D (2005) In vitro cultures of plants from the Rhamnaceae: shoot propagation and anthraquinones pro duction. Pharmaceutical Biology 43:420424 Medan D (1994) Reproductive biology of Frangula alnus (Rhamnaceae) in southern Spain. Plant Systematics and Evo lution 193:173186 Sharma J, Graves WR (2005) Propagation of Rhamnus alnifo lia and Rhamnus lanceolata by seeds and cuttings. Journal of Environmental Horticulture 23:8690 Frangula alnus 58 EN: narrowleaved ash EL: νερόφραξος ES: fresno de hoja estrecha FR: frêne oxyphylle IT: frassino meridionale PT: freixodefolhasestreitas Distribution and Ecology General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Caucasus, Western Asia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Tunisia, Algeria, Morocco In the Mediterranean region, Fraxinus angustifolia Diagnostic traits Fraxinus angustifolia grows to a height of 15 to 20 m. The leaves are deciduous and composed of (3)5 to 13(15) lanceolate, serrate leaflets. Its brownish buds make it possible to differentiate this ash from Fraxinus excelsior (common ash), a species with black terminal buds. Another diagnostic trait that clearly differentiates these species is the inflorescence, which is a raceme in F. angustifolia and a panicle in F. excelsior. F. angusti folia usually exhibits fewer, and smaller, leaflets per leaf. In addition, in F. angustifolia the number of leaflet teeth is equal to or lower than the number of lateral nerves and the teeth arch outwards, whereas in F. excelsior Fraxinus angustifolia Vahl. grows in riparian forests, normally in the high areas of banks that are occasionally flooded for short periods of time, in contact with zonal vegetation. It is some times found in valley bottoms with a high groundwa ter table or in cool, shady forests. It grows in pure stands or mixed with other tree species. In some areas of its eastern distribution range it also grows in sweetwater swamps. Although somewhat indifferent to substrate, this species prefers decarbonated, sandy textured soils. there are more teeth than lateral nerves and they point towards the apex of the leaflet. Another distinctive fea ture is that F. angustifolia usually has fewer flowers (or fruits) per inflorescence than F. excelsior (15 to 20 vs. 50 to 150). F. angustifolia tolerates swampy soils better than F. excelsior and likes higher temperatures. F. angustifolia is easily distinguished from Fraxinus ornus, since the latter’s flowers have white petals that cluster in striking terminal inflorescences. F. ornus does not usually mix with riparian vegetation, but grows on sunny slopes in coniferous, leafy or mixed forests. 59 Fraxinus angustifolia Oleaceae Reproductive biology Sex expression ■ andromonoecy Flowering inconspicuous flowers, clustered in racemes ■ from February to May, before leaf development ■ Pollination ■ anemophilous Variation and Hybridisation Three subspecies have been described on the basis of samara shapes and leaflet numbers. Each subspecies is found in a rather welldefined geographical area: spp. angustifolia in the western Mediterranean region; spp. oxycarpa (Bieb. ex Willd.) Franco & Rocha Alfonso in east central Europe and southern Europe, from NE Spain eastwards; and spp. syriaca (Boiss.) Yalt. in Turkey and eastwards to Iran. This determination based on ge ographical structure is also supported by phylogeo graphical studies using molecular techniques (Heuertz et al., 2006). However, it must be remembered that there are intermediate forms between the above taxa Fruiting Ripening ■ ■ distally winged samara ■ 2040 mm long from September to October ■ dispersal by wind (Fraxigen, 2005), as well as hybrids of F. angustifolia and F. excelsior in areas where the two species are in contact (FernándezManjares et al., 2006; Gerard et al, 2006). Genetic studies of F. angustifolia (Fraxigen, 2005) esti mate high levels of gene flow, transported between stands by pollen, and high variation between individu als within the same stand, due to the pollination pat tern of this species. These results suggest that the collection unit for a single lot may cover a more or less large area that includes several stands. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from October gathering by hand, using longhandled tools or beating branches sequence for fruits that can be sown directly ■ purity: 9099 % This species exhibits interannual variation in fruit pro duction and in some years there is almost no fruit at all. The proportion of fruit with empty seeds is also high, due to predation and seed abortion. Samaras are collected in autumn, when they are brown. High temperatures should be avoided in the period be 40100 g (samaras) T: 4 ºC MC: 48 % ■ airtight container ■ tween harvesting and fruit processing, since fermen tation may occur (Piotto and Piccini, 2000). Treated samaras that are ready to germinate can be preserved for a year at a temperature of –3 ºC. The method in cludes hot stratification for 15 days followed by cold stratification for an additional 15 days and drying to a 9.5% moisture content (Piotto, 1997). Fraxinus angustifolia 60 Germination under controlled conditions Pregermination treatments ■ ■ prechilling (616 weeks) preheating (4 weeks) + prechilling (48 weeks) Conditions ■ 25 / 4 ºC The seeds of Fraxinus angustifolia are subject to phys iological dormancy and require temperature fluctua tions to germinate. If samaras are exposed to constant Nursery production Sowing season ■ autumn, without treatment, or early spring, with treatment Germination Viability ■ 5080 % or only slightly fluctuating temperatures, a secondary dormancy may be induced (Piotto, 1994). Nursery practice bareroot: 200250 g/m2; circumference up to 68 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ Emergence ■ the first spring; 23 weeks after spring sowing Vegetative propagation References However, in vitro propagation is possible (PerezParrón et al., 1994; Tonon et al., 2001a; Tonon et al., 2001b). General references Specific references Amaral Franco J do, Rocha Alfonso ML da (1972) Fraxinus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 3. Cambridge Uni versity Press, Cambridge FernándezManjarres JF, Gerard PR, Dufour J, Raquin C, Fras cariaLacoste N (2006) Differential patterns of morphological and molecular hybridization between Fraxinus excelsior L. and Fraxinus angustifolia Vahl (Oleaceae) in eastern and western France. Molecular Ecology 15:3245–3257 Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Fraxigen (2005) Ash species in Europe. Biological characteris tics and practical guidelines for sustainable use. Oxford Forestry Institute, University of Oxford, UK Gerard PR, FernándezManjarrés JF, FrascariaLacoste N (2006) Temporal cline in a hybrid zone population between Fraxinus excelsior L. and Fraxinus angustifolia Vahl. Molecular Ecology 15:3655–3667 Heuertz M, Carnevale S, Fineschi S, Sebastiani F, Hausman JF, Paule L, Vendramin GG (2006) Chloroplast DNA phylogeogra phy of European ashes, Fraxinus sp. (Oleaceae): roles of hy bridization and life history traits. Molecular Ecology 15:21312140 61 Fraxinus angustifolia Fraxinus angustifolia does not form adventitious roots, so vegetative propagation using cuttings is not viable. PérezParrón MA, GonzálezBenito ME, Pérez C (1994) Mi cropropagation of Fraxinus angustifolia from mature and ju venile plant material. Plant Cell Tissue and Organ Culture 37:297302 Piotto B (1994) Effects of temperature on germination of stratified seeds of three ash species. Seed Science and Tech nology, 22:519529 Piotto B (1997) Storage of nondormant seeds of Fraxinus an gustifolia Vahl. New Forest 14:157166 Piotto B, Piccini C (2000) Dormenza, germinazione e conser vazione dei semi dei frassini spontanei in Italia. Sherwood 52:1923 Tonon G, Capuana M, Di Marco A (2001a) Plant regeneration of Fraxinus angustifolia by in vitro shoot organogenesis. Sci entia Horticulturae 87:291301 Tonon G, Kevers C, Thomas G (2001b) Changes in polyamines, auxins and peroxidase activity during in vitro rooting of Frax inus angustifolia shoots: an auxinindependent rooting model. Tree Physiology 21:655663 Fraxinus angustifolia 62 EN: common ivy EL: κισσός ES: hiedra FR: lierre IT: edera PT: hera Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Is rael, Egypt, Libya, Tunisia, Algeria, Morocco Diagnostic traits This species is a perennial climbing plant that can reach 30 m in height. Its leaves are alternate and poly morphic: leaves of the sterile branches are usually cor date or palmate with 3 to 5 lobes; leaves of the fertile branches are usually entire or subentire, elliptic, ovate or rhombic. In general, the name ‘ivy’ includes not only H. helix L., but also H. hibernica (G. Kirchn.) Bean., H. maderensis K. Koch ex A. Rutherf. and other species with more or less welldefined areas of distribution. Hedera helix L. Common ivy is indifferent to the mineral nature of the substrate and can grow on swampy or very dry land; however, it has a preference for moist, fertile soils. It is found in forests, in moist thickets, on rocky walls and in shady ravines and is very common in Mediterranean riparian forests. These taxa are not easily differentiated and individu als with intermediate characteristics are found. Diag nostic traits are mostly related to leaf trichome characteristics. Hedera helix is a diploid species and H. hibernica is tetraploid (Vargas et al., 1999). 63 Hedera helix Araliaceae Reproductive biology Sex expression ■ hermaphroditism Flowering yellowishgreen flowers, clustered in umbels ■ from July to December ■ Pollination ■ ■ entomophilous selfincompatible Although seeds are dispersed from November to June, peak berry consumption occurs from April to May, or Variation and Hybridisation The interspecific taxonomic complexity also applies in traspecifically and several subspecies have been de scribed as occurring in different geographic ranges, in varying numbers depending on the author (Metcalfe, 2005; Valcárcel et al., 2003; Webb, 1968). Genetic studies using molecular markers have identified the western Mediterranean region as the area of greatest genetic diversity in Hedera species, with geographical Seed propagation Not much information is available on the sexual prop agation of ivy, given the enormous ease with which the Fruiting Ripening ■ ■ black subglobose berry ■ 79 mm from November to June ■ dispersal by frugivorous vertebrates before January/February in a hard winter (Metcalfe, 2005). variation patterns for the different types found (Grivet and Petit, 2002). It is therefore advisable to be cautious when moving reproductive materials from one place to another, at least at a regional scale. This precaution is of benefit in terms of promoting the use of the au tochtonous taxon of each different territory, given that identification is quite a problem for nonspecialists. plant propagates vegetatively. Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from autumn to spring gathering by hand or using longhandled tools sequence for fleshy fruits ■ seed weight / kg fruit: (data not found) ■ purity: 8090 % H. helix is a shady or semishady species, but it is usu ally the individuals in the sun that flower and bear fruit. It is advisable to remove the pulp, which contains germination inhibitors, although fruit sowing is a com 1935 g T: 01 ºC MC: 5560 % for fruits ■ airtight container ■ mon practice in nurseries. Care must be taken to pre vent water loss from fruits during storage. Fruit lots may be stored for 3 to 4 months in a damp place. Hedera helix 64 Germination under controlled conditions ■ prechilling (4 weeks) Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Conditions ■ 29 / 6 ºC Type of cutting ■ semihardwood Position along the shoot basal or middle ■ Nursery practice ■ Vegetative propagation is the method commonly used to produce ivy plants. Multiplication is relatively sim ple, although it is necessary to work with young mate rial because adult tissues do not form roots and do not respond to auxin treatments (Geneve, 1991; Geneve et al., 1988). Since cuttings with longer internodes form more and better roots, it is advisable to collect cuttings from mother plants located in shady areas, which tend to form shoots that have longer internodes and are less lignified than those from plants which receive direct sunlight (Mortensen and Larsen, 1989). The best cut References ■ the first spring; 14 weeks after spring sowing full sunlight reduce growth (Mortensen and Larsen, 1989). Number of internodes Size 12 6570 % Emergence forestpot 300 cm3: 1/0 or 2/0 Cultivation in partial shade with temperatures around 20 ºC is recommended, since high temperatures and Vegetative propagation Germination Viability Collecting time summer Auxin concentration none or < 0.5 % tings are obtained from the internodes located in the middle and lower thirds of the stems (Poulsen and An dersen, 1980). Vegetative propagation is also possible using petioles from which the leaf blade has been re moved (Geneve et al., 1988). In vitro propagation of ivy is possible using nonligni fied segments of stems. It is possible to obtain more microcuttings per explant if the apical bud is removed from the stems (Aljuboory et al., 1991; Auderset et al., 1996; Awad and Banks, 1981; Banks 1979). General references Specific references Flynn S, Turner RM, Stuppy WH (2006) Seed Information Database (release 7.0, Oct. 2006) (online URL http://www.kew.org/data/sid) Aljuboory KH, Williams DJ, Skirvin RM (1991) Growthregula tors influence root and shoot development of micropropa gated algerian ivy. HortScience 26:10791080 Valcárcel V, McAllister HA, Rutherford A, Mill RR (2003) Hedera L. In: Nieto Feliner G et al., (eds). Flora Ibérica. Vol 10. CSIC, Madrid Auderset G, Moncousin C, Rourke J, Morre DJ (1996) Stimu lation of root formation by thiol compounds. HortScience 31:240243 Webb DA (1968). Hedera L. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Awad AEE, Banks MS (1981) Callus initiation and development of Hedera helix L. as affected by auxin and cytokinin in the media. Gartenbauwissenschaft 46:116119 65 Hedera helix Pregermination treatments Banks MS (1979) Plant regeneration from callus from two growth phases of English ivy, Hedera helix L. Zeitschrift fur Pflanzenphysiologie 92:349353 Geneve RL (1991) Patterns of adventitious root formation in English ivy. Journal of Plant Growth Regulation 10:215220 Geneve RL, Hackett WP, Swanson BT (1988) Adventious root initiation in debladed petioles from the juvenile and mature phase of English ivy. Journal of the American Society for Hor ticultural Science 113:630635 Grivet D, Petit RJ (2002) Phylogeography of the common ivy (Hedera sp.) in Europe: genetic differentiation through space and time. Molecular Ecology 11:1351–1362 Metcalfe D (2005) Hedera helix L. Journal of Ecology 93:632648 Mortensen LM, Larsen G (1989) Effects of temperature on growth of six foliage plants. Scientia Horticulturae 39:149159 Poulsen A, Andersen AS (1980) Propagation of Hedera helix: Influence of irradiance to stock plants, length of internode and topophysis of cutting. Physiologia Plantarum 49:359365 Vargas P, McAllister HA, Morton C, Jury SL, Wilkinson MJ (1999) Polyploid speciation in Hedera (Araliaceae): phyloge netic and biogeographic insights based on chromosome counts and ITS sequences. Plant Systematics and Evolution 219:165179 Hedera helix 66 Distribución general: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern, Middle and Eastern Asia, Siberia, China, Eastern and Western Canada, Northeastern, NorthCentral, Northwestern, Southeastern, SouthCentral and South western U.S.A., Mexico Mediterranean region: Portugal, Spain, France (incl. Diagnostic traits Humulus lupulus is the only hop species found in Eu rope. It is a rhizomatous plant with an annual lianoid aerial stem, equipped with trichomes that it uses for Reproductive biology ■ dioecy Flowering yellowishgreen flowers, male inflores cences clustered in panicles, female inflorescences, similar to cones, solitary or clustered in cymes ■ from May to August ■ Pollination ■ Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey Common hop is found in cool, humid environments in temperate and cold areas and in riparian forests in the Mediterranean region. It grows on moist, occasionally swampy, alkaline to slightly acid soils. support, and may grow to a height of 5 to 10 m. Its leaves are generally opposed, widely ovatecordate, with 3 to 5 coarsely dentate lobes. anemophilous Fruiting Ripening ■ ■ globose achene, covered by yellow glands ■ about 3 x 2.5 mm from September to October ■ dispersal by wind 67 Humulus lupulus Distribution and Ecology Sex expression Humulus lupulus L. EN: common hop EL: λυκίσκος ES: lúpulo FR: houblon IT: luppolo PT: engatadeira Cannabaceae Variation and Hybridisation Small (1978) identified several hop varieties on the basis of quantitative and qualitative morphological leaftraits and geographical distribution. European populations would mostly be included under H. lupulus var. lupulus. Later phylogenetic studies using DNA have suggested the existence of two main types, European Seed propagation The hop is not usually sexually propagated, due to the difficulties of collecting reasonable amounts of seed and Asian/North American, while China is possibly the origin of the genus (Murakami et al., 2006). The Euro pean type seems to exhibit a low level of genetic vari ation as compared to the North American type, probably due to rapid, recent expansion. and to its low viability. Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from September to October ■ gathering by hand or using longhandled tools sequence for dehiscent fruits ■ seed weight / kg fruit: (data not found) ■ purity: 95 % Germination under controlled conditions Pregermination treatments ■ prechilling (510 weeks) Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Conditions ■ 25 / 15 ºC (8 / 16 h) Nursery practice ■ forestpot 300 cm3: 1/0 or 2/0 The seeds should be covered thinly after sowing. Seedlings are very delicate and are susceptible to frost or cold injury. It is possible to sow in small pots (volume T: 4 ºC MC: 48 % ■ airtight container 2.8 3.5 g ■ Germination Viability ■ 95 % Emergence ■ spring; 3 to 4 weeks after sowing up to 7075 cm3). Once the seedlings have become es tablished in these smaller cells, they can be removed and transplanted into the growth containers. Humulus lupulus 68 Type of cutting ■ ■ softwood rhizome Position along the shoot indifferent Number of internodes Size 2 10 cm Hops are normally propagated by means of rhizomes and also by softwood cuttings (Buzi, 2000). This species produces very long rhizomes from which a great quan tity of propagation material may be obtained. The roots are cut into pieces at the end of the growth period and buried horizontally in sand. Once the cuttings have sprouted, they are transferred to a container. The re generative capacity of aerial cuttings also makes these an easy propagation method, although strongly de pendent on the clone. Hormone treatment accelerates rooting and helps to make it more uniform (Howard, 1967). Summer cuttings, using material from the mid dle part of the sets, should be held in a mist environ ment. Howard (1965) recommends using cuttings with References General references Catalán P (1993) Humulus L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid Ellis RH, Hong TD, Roberts EH (1985) Handbook of Seed Tech nology for Genebanks Volume II. Compendium of Specific Germination Information and Test Recommendations Hand books for Genebanks: No. 3. IPGRI, Rome Flynn S, Turner RM, Stuppy WH (2006) Seed Information Da tabase (release 7.0, Oct. 2006) (online URL http://www.kew.org/data/sid) Collecting time springsummer winter Auxin concentration none or < 0.5 % none two internodes and leaving the leaves on the upper in tenode to maintain the photosynthetic activity of the cutting and to promote the accretion of carbohydrates to the basal area. Long days (16 hours of light) and good illumination help to produce more and better roots (Howard and Sykes, 1966). In vitro propagation is possible, although there are marked differences in the capacity of different individ uals to respond to this method. Since this plant is of great agricultural interest, several protocols for mass micropropagation exist (Fortes and Pais, 2000; Gurri arán et al., 1999; Roy et al., 2001; Smykalova et al., 2001). regeneration in cultures of Humulus lupulus L. (hop) cvs. Bre wers Gold and Nugget. Plant Cell Reports 18:10071011 Howard BH (1965) Regeneration of the hop plant (Humulus lupulus L.) from softwood cuttings. I. The cutting and its roo ting environment. Journal of Horticultural Science 40:181 191 Howard BH (1967) Regeneration of the hop plant (Humulus lupulus L.) from softwood cuttings. III. Trating with rootpro moting substances. Journal of Horticultural Science 42:105 Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Howard BH, Sykes JT (1966) Regeneration of the hop plant (Humulus lupulus L.) from softwood cuttings. II. Modification of carbohydrate ressources within cutting. Journal of Horti cultural Science 41:155 Tutin TG, Edmonson JR (1993) Humulus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Murakami A, Darby P, Javornik B, Pais MSS, Seigner E, Lutz A, Svoboda P (2006) Molecular phylogeny of wild Hops, Humu lus lupulus L. Heredity 97:6674 Specific references Buzi A (2000) Il luppolo come pianta ornamentale. Colture Protette 29:6370 Fortes AM, Pais MS (2000) Organogenesis from internodede rived nodules of Humulus lupulus var. Nugget (Cannabina ceae). American Journal of Botany 87:971979 Gurriaran MJ, Revilla MA, Tames RS (1999) Adventitious shoot Roy AT, Leggett G, Koutoulis A (2001) Development of a shoot multiplication system for hop (Humulus lupulus L.). In Vitro Cellular and Developmental Biology Plant 37:7983 Small E (1978) A numerical and nomenclatural analysis of morphogeographic taxa of Humulus. Systematic Botany 3:3776 Smykalova I, Ortova M, Lipavska H, Patzak J (2001) Efficient in vitro micropropagation and regeneration of Humulus lupulus on low sugar, starchGelrite media. Biologia Plantarum 44:712 69 Humulus lupulus Vegetative propagation Laurus nobilis L. Lauraceae EN: bay tree EL: δάφνη ES: laurel FR: laurier sauce IT: alloro PT: loureiro Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa of many bay laurel populations, since the tree has been widely cultivated in the Mediterranean region. It is difficult to determine the autochthonous nature The bay laurel is sensitive to cold and grows in tem perate and moderately humid regions, where it is usu ally found near the coast. It grows scattered in damp forests, shady ravines and valley bottoms and among riparian vegetation. More rarely, it can grow in pure stands or as the dominant species in particularly humid coastal areas. Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel, Libya, Tunisia, Algeria, Morocco Diagnostic traits L. nobilis is a small to mediumsized perennial tree that reaches 5 to 10 m in height. Its young twigs are glabrous and its leaves are oblonglanceolate, coria ceous, glabrous and aromatic. It can be distinguished Reproductive biology Sex expression ■ dioecy Flowering Laurus nobilis 70 yellowishgreen or whitish flowers, clustered in umbels, 4 to 6 flowers in each ■ from February to May ■ Pollination ■ from L. azorica (Seub.) Franco, which is found in the Macaronesian islands and the north of Africa, in that the latter’s leaves are initially somewhat hairy on the back and its young twigs are densely hairy. entomophilous Fruiting Ripening ■ ■ black, ovoidglobose berry ■ 1015 mm from September to October ■ dispersal by frugivorous vertebrates Variation and Hybridisation There is no information on intraspecific variation and hybridisation for this taxon. Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from September to October ■ gathering by hand or using longhandled tools sequence for fleshy fruits ■ seed weight / kg fruit: (data not found) ■ purity: 98 % The seeds of the sweet bay can be preserved for 48 months at 0 ºC and must be treated as recalcitrant (Konstantinidou et al., 2007); care must be taken to prevent desiccation during cleaning and storage. It is advisable to remove the pulp of the fruits because it contains germination inhibitors (Takos, 2001; Tilki, ■ prechilling (4–12 weeks) Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Conditions ■ ■ 20 ºC light Nursery practice ■ ■ ■ 2004; Sari et al., 2006). However, direct fruit sowing is possible. This is a common practice in nurseries because it reduces handling and allows 2 to 4 months storage of lots provided that any loss of water content from the fruits is prevented over this period. Germination under controlled conditions Pregermination treatments T: 01 ºC MC: 5560 % ■ open container 8301000 g forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Germination Viability ■ 5070 % Emergence ■ the first spring, complete within 23 months 71 Laurus nobilis Tolerance to desiccation: RECALCITRANT Vegetative propagation Type of cutting ■ semihardwood Position along the shoot basal or middle Number of internodes Size 2 / 5 10 cm Propagation of bay laurel by cuttings is difficult (Raviv et al., 1983; Viola et al., 2004). The capacity to produce adventitious roots is highly variable between individu als. The best results are obtained by collecting cuttings in summer, from juvenile parent plants with profuse leaves (Piccioni et al., 1996). Raviv and Putievsky (1984) recommend rooting in hotbeds in a mist atmosphere, using a mixture of peat and perlite (1:1) as substrate. References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Collecting time August to September Auxin concentration 0.5 % Bay laurel can also be propagated by aerial layering, although this method is not practical if many plants are required. In vitro propagation of bay laurel from axillary buds has been successfully attempted (Souayah et al., 2002). Raviv M, Putievsky E (1984) Rooting of stem cuttings of bay laurel: rooting media and fungicidal treatments. Hassadeh 64:22472249 Raviv M, Putievsky E, Ravid U, Senderovitch D, Snir N, Roni R (1983) Native bay laurel (Laurus nobilis L.) as an ornamental plant. Acta Horticulturae 132:3542 Sari AO, Oguz B, Bilgic A (2006) Breaking seed dormancy of laurel (Laurus nobilis L.). New Forests 31:403408 Tutin TG (1993) Laurus L. In: Tutin et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Souayah N, Khouja ML, Khaldi A, Rejeb MN, Bouzid S (2002) Breeding improvement of Laurus nobilis L. by conventional and in vitro propagation techniques. Journal of Herbs, Spices and Medicinal Plants 9:101105 Villar L (1986) Laurus L. In: Castroviejo S et al. (eds). Flora Ibé rica. Vol 1. CSIC, Madrid Takos I (2001) Seed dormancy in bay laurel (Laurus nobilis L.). New Forests 21:105–114 Specific references Tilki F (2004) Influence of pretreatment and desiccation on the germination of Laurus nobilis L. seeds. Journal of Environ mental Biology 25:157161 Konstantinidou E, Takos I, Merou T (2007) Desiccation and sto rage behavior of bay laurel (Laurus nobilis L.) seeds. European Journal of Forest Research 127: 125131 Piccioni E, Longari F, Standardi A, Ciribuco S (1996) Propaga zione per talea e allevamento in vaso di alcune specie arbus tive. Informatore Agrario 52:8791 Viola F, Forleo LR, CocozzaTalia MA (2004) Propagazione aga mica di alcune specie della macchia mediterranea. Italus Hor tus 11:186190 Laurus nobilis 72 General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Northern Africa Mediterranean region: Portugal, Spain, France, Italy, Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Morocco Diagnostic traits Ligustrum vulgare is a shrub of 1 to 5 m in height, nor mally deciduous although it can keep its leaves in warm climates. Its leaves are opposite, ellipticlanceolate to oblanceolate. In Europe there are many nonnative or Reproductive biology ■ hermaphroditism Flowering white flowers, clustered in thyrses ■ from May to July ■ Pollination ■ The common privet withstands cold continental cli mates, but with warm summers. It is found as scattered individuals in thorny thickets, ravines, glades and river side areas. It prefers limy soils with clayey or silty tex tures and a certain amount of humidity. namental taxa that must be avoided in restoration projects, such as the perennial privets from Eastern Asia: Ligustrum lucidum Aiton, a small tree, and Ligus trum ovalifolium Hassk, a shrub. entomophilous Fruiting Ripening ■ ■ ■ black globose berry 68 mm from September to October, remaining on the tree in winter ■ dispersal by frugivorous vertebrates 73 Ligustrum vulgare Distribution and Ecology Sex expression Ligustrum vulgare L. EN: common privet EL: αγριομυρτιά ES: aligustre FR: troène commun IT: ligustro PT: alfenheiro Oleaceae Variation and Hybridisation Differences in the amount of fruit production, fruit size, and number of seeds per fruit have been observed be tween individuals of these species (Obeso and Grubb, 1993). These differences may affect the genetic varia tion of collected seed lots; so similar amounts of fruit and seeds should be collected from each individual. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from September to December ■ gathering by hand or using longhandled tools sequence for fleshy fruits ■ seed weight / kg fruit: 66290 g ■ purity: 90100 % ■ Germination under controlled conditions Pregermination treatments ■ prechilling (812 weeks) Nursery production Sowing season ■ autumn, without treatment, or early spring, with treatment Vegetative propagation Type of cutting ■ ■ hardwood semihardwood Position along the shoot indifferent basal Conditions ■ Germination Viability 20 / 10 ºC ■ Nursery practice bareroot: 50 g/m2; circumfe rence up to 46 cm or total height up to 80100 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ Number of internodes Size 20 cm 10 cm Ligustrum vulgare 74 Common privet is easily reproduced by vegetative prop agation. It is advisable to plant the cutting directly in the container (Mac Cárthaig and Spethmann, 2000) at the end of winter to prevent frost damage. Hansen and Kristiansen (2000) recommend collecting semihard T: 4 ºC MC: 48 % ■ airtight container 825 g 7496 % Emergence ■ the first spring Collecting time winter July to September Auxin concentration none or 0.5 % none or 0.5 % wood cuttings at the end of summer, because the root ing capacity of material collected in October or later diminishes rapidly. It may be possible to propagate privet using root cuttings, since it is a species that is able to produce root suckers naturally. References General references Specific references Amaral Franco J do (1972) Ligustrum. In: Tutin TG et al. (eds). Flora Europaea. Vol 3. Cambridge University Press, Cambridge Hansen J, Kristiansen K (2000) Root formation, bud growth and survival of ornamental shrubs propagated by cuttings on different planting dates. Journal of Horticultural Science and Biotechnology 75:568574 Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Obeso JR, Grubb PJ (1993) Fruit maturation in the shrub Ligus trum vulgare (Oleaceae): lack of defoliation effects. Oikos 68:309316 Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma 75 Ligustrum vulgare Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Liquidambar orientalis Mill. Altiginaceae EN: oriental sweet gum EL: υγραδάμπαρη ES: liquidámbar oriental FR: liquidambar oriental, copalme d'Orient IT: liquidambar orientale PT: liquidâmbaroriental Distribution and Ecology General distribution: Western Asia Oriental sweet gum grows on dry slopes and in humid areas such as riverside zones, marshy places and the bottom of valleys. Optimal growth is on deep, moist, nutrientrich soils. Mediterranean region: Greece (Rodhos), Turkey Diagnostic traits Liquidambar orientalis is a deciduous tree that grows to a height of 30 to 35 m. Its palmatifid leaves have 5 lobes and finely sinuatedentate or serrate margins. They are glabrous or, more rarely, exhibit sparse tufts of hair beneath, at the base of the main veins. The prin Reproductive biology Sex expression ■ monoecy Flowering small flowers clustered in globose inflorescences, male inflorescences in terminal racemes, solitary female inflorescences ■ from March to May ■ Liquidambar orientalis 76 Variation and Hybridisation Pollination ■ cipal lobes of the leaves usually have secondary lobes. This trait makes it easy to distinguish this species from L. stryraciflua, an American species widely used for or namental purposes. entomophilous Two varieties are described: L. orientalis var. orientalis and L. orientalis var. integriloba. In the latter the lobes Fruiting Ripening ■ ■ capsules arranged helically in woody infructescence, 25 to 30 capsules in each ■ infructescence 2.53 cm from November to December ■ dispersal by wind of the leaves are not divided, while in the former they are. In addition, two morphological types have been distinguished in relation to the ability to produce bal sam: oilproducing trees are smaller and have longer branches and larger barkscales than nonproducers (Alan and Kaya, 2003). It would seem there are certain coldadaptation differences between populations lo cated at altitudes of less than four hundred metres (plain sweet gum) or more than four hundred meters (mountain sweet gum) (Alan and Kaya, 2003). Seed propagation Liquidambar orientalis is usually produced from seed; however, no data have been found regarding its pro duction, possibly due to its restricted distribution and more or less local use. As a general guideline, data for Liquidambar styraciflua are supplied. Nevertheless, it This species has a greater morphological and genetic likeness to L. stryraciflua L. than to eastern Asian sweet gum species (Hoey and Parks, 1991; Ickert Bond et al., 2005; IckertBond and Wen, 2006). It may hybridise with the American taxon and produce indi viduals with a higher number of seeds per fruit (San tamour, 1972). should be borne in mind that although the number of seeds per fruit is very similar in both plants, the seed length is greater in L. orientalis (IckertBond et al., 2005), so the weight per kilo of fruit and per 1,000 seeds would be higher than the values indicated. Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from November to December ■ climbing or using longhandled tools sequence for dehiscent fruits, natural drying ■ seed weight / kg fruit: 3090 g (L. styraciflua) ■ purity: 9095 % Oriental sweet gum produces fruit every year. Abun dant crops, however, are more common every three years (Alan and Kaya, 2003). Infructescences are col 47 g (L. styraciflua) lected when their green colour loses its brightness and starts to turn yellowish. Germination under controlled conditions Pregermination treatments ■ prechilling (4–6 weeks) Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Conditions ■ 30 / 20 ºC Nursery practice ■ bareroot: 100 g/m2 Seeds are very sensitive to dehydration during germi nation, so the substrate must be kept moist. T: 4 ºC MC: 1015 % ■ airtight container (L. styraciflua) ■ Germination Viability ■ 5070 % (L. styraciflua) Emergence ■ the first spring 77 Liquidambar orientalis Tolerance to desiccation: ORTHODOX Vegetative propagation Type of cutting ■ semihardwood Position along the shoot basal or middle Number of internodes Size 23 No references to vegetative propagation of Liqui dambar orientalis have been found, although there are studies for L. styraciflua and L. formosana, which are species of marketing interest. Both will reproduce by vegetative propagation, although with difficulty, using semihardwood cuttings: survival rates are always below 60%, even under optimal conditions (He et al., 2004; Sutter and Barker, 1985). References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Peşmen H (1972) Liquidambar L. In: Davis PH (ed). Flora of Turkey and East Aegean Islands. Vol 4. University Press, Edinburgh Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Alan M, Kaya Z (2003) EUFORGEN Technical Guidelines for ge netic conservation and use for oriental sweet gum (Liq uidambar orientalis). International Plant Genetic Resources Institute, Rome Brand MH (1990) Sweetgum tissue culture. Combined Proce edings of the International Plant Propagators Society 40:586 590 Brand MH, Lineberger RD (1991) The effect of leaf source and developmental stage on shoot organogenic potential of swe etgum (Liquidambar styraciflua L.) leaf explants. Plant Cell Tis sue and Organ Culture 24:17 Collecting time summer Auxin concentration 1% In vitro propagation seems a more effective alternative. Erdag and Emek (2005) managed to regenerate adult individuals of oriental Liquidambar from axillary buds. There are several references to micropropagation of the American and Asian species of Liquidambar (Brand, 1990; Brand and Lineberger, 1991; Durkovich et al., 2005). Durkovic J, Pichler V, Lux A (2005) Micropropagation with a novel pattern of adventitious rooting in Formosan sweetgum. Canadian Journal of Forest Research 35:27752780 Erdag B, Emek Y (2005) In vitro adventitious shoot regenera tion of Liquidambar orientalis Miller. Journal of Biological Sciences 5:805808 He GP, Chen YT, Luo WJ, Zhang JZ, Feng JM, Xu YQ (2004) Study on the technical of cutting propagation of tender branch for broadleaf tree species. Forest Research, Beijing 17:810814 Hoey MT, Parks CR (1991) Isozyme divergence between East ern Asian, North American, and Turkish species of Liquidambar (Hamamelidaceae). American Journal of Botany 78:938947 IckertBond SM, Pigg KB, Wen J (2005) Comparative in fructescence morphology in Liquidambar (Altingiaceae) and its evolutionary significance. American Journal of Botany 92:12341255 IckertBond SM, Wen J (2006) Phylogeny and biogeopraphy of Altiginaceae: Evidence from combined analysis of five non coding chloroplast regions. Molecular Phylogenetics and Evo lution 39: 512528 Santamour FS (1972) Interspecific hybridization in Liqui dambar. Forest Science 18:2326 Sutter EG, Barker PB (1985) In vitro propagation of mature Li quidambar styraciflua. Plant Cell Tissue and Organ Culture 5:1321 Liquidambar orientalis 78 EN: honeysuckle EL: αγιόκλημα ES: madreselva FR: chèvrefeuille IT: caprifoglio PT: madressilva Lonicera etrusca G. Santi Lonicera implexa Aiton Lonicera implexa Lonicera etrusca Caprifoliaceae General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa Lonicera etrusca Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel, Tunisia, Al geria. Morocco Lonicera implexa Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna, Sicilia), Cro atia, BosniaHerzegovina, Montenegro, Albania, Gre ece, Tunisia, Algeria, Morocco Lonicera etrusca and L. implexa are thermophile hon eysuckles with a wide distribution in the European Mediterranean region. Other honeysuckles that require cooler environments, like L. periclymenum, may form part of the lianoid layer of riparian vegetation in Mediterranean areas. All these species also grow in hedges, scrub and open forests with a certain level of humidity. 79 L. etrusca - L. implexa Distribution and Ecology Diagnostic traits Both species are woody climbers with decussate leaves, the first pair connate below the inflorescence, and flowers arranged in terminal glomerules. L. implexa is perennial, with coriaceous leaves and sessile inflores cences, while L. etrusca is deciduous, with pedunculate inflorescences that are sometimes accompanied by an other two lateral glomerules. Both species are easily differentiated from L. periclymenum because the top leaves of the later have a short petiole. L. implexa, with two to nine flowers per cluster, must not be confused with L. splendida, a perennial Hispanic endemism that Reproductive biology Sex expression ■ hermaphroditism Flowering yellowishwhite flowers, often tinged with purple ■ from May to August ■ has flowers with longer styles and stamens. Another climber that is similar, although found in cooler cli mates, is L. caprifolium L., which has sessile inflores cences with connate leaves below them; it is deciduous, and thus easily identifiable in winter. It is not advisable to employ L. japonica in restoration projects. This is an Asian species that is very often used in gardening and is considered invasive. Its flowers, arranged in pairs on axillary peduncles, are initially white and turn yellow when mature, and its fruits are blue. Pollination ■ entomophilous Fruiting Ripening ■ ■ ■ reddish berry 48 mm from September to October, sometimes later ■ dispersal by frugivorous vertebrates Variation and Hybridisation There is no information on intraspecific variation and hybridisation for these taxa. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from September to October ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 3076 g (L. etrusca); 118157 g (L. implexa) ■ purity: 9599 % L. etrusca - L. implexa 80 Honeysuckle crops can suffer great losses due to at tacks by lice, which vary in severity from year to year (Jordano, 1990). Honeysuckle fruits should be collected 711 g (L. etrusca) 1114 g (L. implexa) T: 0 ºC a 4 ºC CH: 48 % ■ envase hermético ■ as soon after ripening as possible to reduce losses to birds. Germination under controlled conditions ■ ■ mechanical scarification scarification with concentrated sulphuric acid (1020 minutes) Conditions ■ 20 / 10 ºC; 20 ºC Although prechilling (48 weeks) is recommended for Lonicera species because they show some embryo dor mancy, these two Mediterranean species appear to Nursery production Sowing season ■ autumn, without treatment, or spring, with treatment Vegetative propagation Type of cutting softwood hardwood ■ root ■ ■ Position along the shoot basal or middle basal or middle Germination Viability ■ have seedcoatconnected dormancy and scarification is enough to germinate the seeds. Nursery practice ■ Emergence forestpot 300 cm3: 1/0 or 2/0 Number of internodes Size 12 10 cm 10 cm Abundant information on vegetative propagation of honeysuckles exists, since the genus Lonicera includes several species and hybrids of ornamental interest which are produced almost exclusively by this method. However, there is little specific information on L. im plexa and L. etrusca. Honeysuckles are usually propa gated from softwood cuttings collected in summer. The best time to harvest is from June onwards (Cabot et al., 2002), since spring cuttings do not give good results. Mac Cárthaig and Espethmann (2000) recommend se rial cutting propagation for rejuvenation of the mate rial. It is advisable to collect material from the middle References General references Bolòs O de, Vigo J (1995) Flora dels Països Catalans. Vol III. Editorial Barcino, Barcelona Browicz K (1976) Lonicera L. In: Tutin TG et al. (eds). Flora Eu ropaea. Vol 4. Cambridge University Press, Cambridge 7097 % ■ the first spring; 58 weeks after spring sowing Collecting time summer winter winter Auxin concentration none or < 0.5 % none or < 0.5 % none or < 0.5 % and basal parts of the stems or sets in a mist environ ment (Podkopaev, 1987). It is also possible to use hard wood (Albrecht and Schulze, 1980) and root cuttings (Götsche, 1978), although these methods are used less frequently. There are several references to in vitro experiments to propagate other species of the genus Lonicera (Kahru, 2003; Boonnour et al., 1988; Georges et al., 1993), which may provide an approach for propagating the species discussed in this guide. Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Gálvez A, Navarro RM (2001) Manual para la identificación y reproducción de semillas de especies vegetales autóctonas de Andalucía. Vol II. Consejería de Medio Ambiente, Junta de An dalucía, Sevilla 81 L. etrusca - L. implexa Pregermination treatments Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Ruiz Téllez T, Devesa JA (2007) Lonicera L. In: Castroviejo S (coord). Flora Ibérica. Vol 15. CSIC, Madrid Specific references monales. In: Cermeño P (ed). I Jornadas Ibéricas de Plantas Ornamentales. Junta de Andalucia. Consejeria de Agricultura y Pesca, Sevilla Georges D, Chenieux JC, Ochatt SJ (1993) Plant regeneration from agedcallus of the woody ornamental species Lonicera japonica cv. “Hall’s Prolific”. Plant Cell Reports 13:9194 Göttsche D (1978) Vermehrung einheimischer Straucharten durch Wurzelschnittlinge. Forstarchiv 49:3336 Albrecht HJ, Schulze G (1980) Vermehrung von Ziergeholzen durch Steckholz in Plastfolienzelten. Gartenbau 27:122124 Jordano P (1990) Biología de la reproducción de tres especies del género Lonicera (Caprifoliaceae) en la Sierra de Cazorla. Anales del Jardín Botánico de Madrid 48:3152 Boonnour K, Wainwright H, Hicks RGT (1988) The micropro pagation of Lonicera periclymenum L. (honeysuckle). Acta Hor ticulturae 226:183189 Karhu ST (2003) Performance of Lonicera microcuttings as af fected by mineral nutrients and genotype. Acta Horticulturae 616:181184 Cabot P, Llauradó M, Busquets M (2002) Estudio del enraiza miento de estaquillas de Teucrium polium spp. capitatum (L.) Arc. y Lonicera implexa Ait. en diferentes concentraciones hor Podkopaev AA (1987) Propagation of ornamental species of Lonicera by green cuttings. Lesnoe Khozyaistvo 1:6566 L. etrusca - L. implexa 82 Myrtus communis L. EN: myrtle, common myrtle EL: μυρτιά ES: mirto FR: myrte IT: mirto PT: murta Myrtaceae Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sicilia), Croatia, Bosnia Herzegovina, Montenegro, Albania, Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel, Libya, Tunisia, Algeria, Morocco The common myrtle is a thermophile species that is typical of the Mediterranean maquis in areas of coastal influence. It prefers noncompact soil with a certain level of humidity and thus can frequently be found next to rivers, in the bottoms of valleys and in shady areas. It grows more frequently on acidreaction soils. It re sprouts vigorously from stumps after fire or cutting. Diagnostic traits Myrtus communis is a perennial, highly aromatic shrub with opposite, decussate leaves, ovatelanceolate, acute, attenuate at base. Sex expression ■ hermaphroditism Flowering white flowers, clustered in panicles ■ from May to August, sometimes also in autumn ■ Pollination ■ ■ entomophilous selfcompatible Fruiting Ripening ■ ■ bluishblack, rarely whitecreamy, ellipsoidal to subglobose berry ■ 610 mm from October to January ■ dispersal by frugivorous vertebrates 83 Myrtus communis Reproductive biology Variation and Hybridisation Genetic studies performed with isoenzymes reveal a high level of variation within populations, as well as between populations that are distant from each other (Messaoud et al., 2006). Some authors have defined a tarentina subspecies, whose leaves are described as smaller. This subspecies may be a naturalised variety which was widely culti vated in the past to make use of the plant’s many dif ferent applications. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ late autumn gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 30125 g ■ purity: 98100 % There is great individual variation in the production of fruit and significant interannual fluctuations also occur ■ prechilling (38 weeks) Conditions ■ Nursery production Sowing season ■ autumn, without treatment, or spring, with or without treatment Myrtle seedlings are very sensitive to cold. Germination Viability 20 ºC Myrtle seeds do not need treatments, but prechilling could be useful to accelerate germination and make it more homogeneous. There are no significant differen ■ ■ 8098 % ces in seed germination capacity between individuals with bluish or white fruits (Traveset et al., 2001). Nursery practice ■ ■ (Cani, 1996; Traveset et al., 2001; Mulas and Fadda, 2004). Germination under controlled conditions Pregermination treatments T: 4 ºC MC: 48 % ■ airtight container 27 g forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Emergence ■ the first spring; complete within 3 months Myrtus communis 84 Type of cutting ■ ■ semihardwood hardwood Position along the shoot basal or middle basal or middle Number of internodes Size 23 15 cm There is abundant information about myrtle propaga tion because of the growing interest in its essential oils. Very good results have been obtained using softwood cuttings harvested from rejuvenated parent plants in July or August, achieving 90% rooting success (Pignati and Crobeddu, 2005). Cutting in summer requires a misted environment (Cervelli, 2005; Scortichini, 1986). Klein et al. (2000) recommend collecting cuttings in November or December and planting at an ambient temperature of 20 °C with bed heating, since these conditions produce the best results (70%). In this species, substrate mixtures of straw, peat and coconut fibre (Crobeddu and Pignati, 2005) or peat and perlite (1:1) (De Vita and Lauro, 2004) have been used. Myrtle References General references Campbell MS (1968) Myrtus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Paiva J (1997) Myrtus L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 8. CSIC, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Specific references Cani MR (1996) Osservazioni sulla biologia e valutazione della biodiversitá naturale per la domesticazione del Myrtus com munis. Tesis de licenciatura. Facoltá di Agraria. Universitá degli Srudi di Sassari, Sassari Cervelli C (2001) Una collezione di mirto per pensare al mer cato. Colture Protette 30:5962 Collecting time summer winter Auxin concentration 0.5 % 0.5 % shows a very high individual variation in the ability to root (Cervelli, 2001; Mulas and Cani, 1996). Acclimati zation of the rooted material is an extremely sensitive stage in this species; the greatest losses occur during this phase (Frau et al., 2001; Milia et al., 1996). Myrtle is successfully regenerated from axillary buds (KhoshKhui et al., 1984; Nobre, 1994; Ruffoni et al., 2003) and meristems (Frau et al., 2001; Morini et al., 2002). Also, the proportion of losses in the acclimati zation phase has been successfully reduced to 3% in plants obtained through in vitro culture (Hatzilazarou et al., 2003). Cervelli C (2005) La specie arbustive della macchia medite rranea. Un patrimonio da valorizzare. Collana Sicilia Foreste 26:39154 Crobeddu S, Pignatti G (2005) Propagazione per talea di spe cie mediterranee. Prove di substrato. Sherwood Foreste ed Al beri Oggi 114:2731 De Vita M, Lauro P (2004) Influenza dei substrati sull’accres cimento di genotipi di mirto coltivato in vaso. Atti VII Giornate Scientifiche SOI, 46 maggio 2004, Napoli Frau A, Cadinu M, Repetto A, Zedda A (2001) Micropropaga zione di cinque cloni di mirto sardo. Informatore Agrario 57:6567 Hatzilazarou S, Grammatikos H, Economou AS, Rifaki N, Ralli P (2003) Rooting in vitro and acclimatization of Myrtus com munis microcuttings. Acta Horticulturae 616:259264 KhoshKhui M, Shekafandeh A, Azarakhsh H (1984) Micro propagation of myrtle. Scientia Horticulturae 22:139146 Klein JD, Cohen S, Hebbe Y (2000) Seasonal variation in roo ting ability of myrtle (Myrtus communis L.) cuttings. Scientia Horticulturae 83:7176 Messaoud C, Khoudja ML, Boussaid M (2006) Genetic diversity and structure of wild Tunisian Myrtus communis L. (Myrtaceae) populations. Genetic Resources and Crop Evolution 53:407–417 85 Myrtus communis Vegetative propagation Milia M, Pinna ME, Satta M, Scarpa GM (1996) Propagazione del mirto (Myrtus communis L.) mediante l’uso di tecniche di verse. Rivista Italiana EPPOS 19:117123 Pignatti G, Crobeddu S (2005) Effects of rejuvenation on cut ting propagation of Mediterranean shrub species. Foresta 2:290295 (online URL: http://www.sisef.it/) Morini S, Frediani F, Onofrio CD (2002) Indagini sulla micro propagazione del mirto. Italus Hortus 9:4148 Ruffoni B, Airo M, Fascella G, Mascarello C, Zizzo G, Cervelli C (2003) Rooting and acclimatization of ornamental myrtle genotypes. Acta Horticulturae 616:255258 Mulas M, Cani MR (1996) Variability of rooting ability of soft wood cuttings in myrtle germplasm. Beitrage zur Zuchtungs forschung Bundesanstalt fur Zuchtungsforschung an Kulturpflanzen 2:191194 Mulas M, Fadda A (2004) First observations on biology and organ morphology of myrtle (Myrtus communis L.) flower. Agricoltura Mediterranea 134:223235 Nobre J (1994) In vitro shoot proliferation of Myrtus communis L. from fieldgrown plants. Scientia Horticulturae 58:253258 Scortichini M (1986) Il mirto. Rivista di Frutticoltura e di Or tofloricoltura 48:4753 Traveset A, Riera N, Mas RE (2001) Ecology of the fruitcolor polymorphism in Myrtus communis and differential effect of birds and mammals on seed germinatrion and seedling growth. Journal of Ecology 89:749760 Myrtus communis 86 General distribution: Southwestern and Southeastern Europa, Western Asia, Arabian Peninsula, Indian Sub continent, China, Northern, West Tropical and North east Tropical Africa Mediterranean region: Portugal, Spain (incl. Balea res), France (incl. Corse), Italy (incl. Sardegna and Si cilia), Croatia, Albania, Greece (incl. Kriti), Cyprus, Diagnostic traits The oleander is a perennial bush that can reach 4 to 6 m in height. Its leaves are lanceolate, with a conspi Reproductive biology ■ hermaphroditism Flowering pink flowers, clustered in corymbs ■ from March to October ■ Pollination ■ ■ Turkey, Syria, Lebanon, Israel, Libya, Tunisia, Algeria, Morocco The oleander is a sunloving species that grows in tem perate climates. It can withstand floods and prolonged periods of drought. In the Mediterranean region it is found next to temporary and permanent watercourses, often dominating the landscape. cuous whitish main vein, coriaceous and glabrous. entomophilous selfcompatible Fruiting Ripening ■ ■ ■ double follicle 816 cm long from December to March ■ dispersal by wind 87 Nerium oleander Distribution and Ecology Sex expression Nerium oleander L. EN: oleander EL: πικροδάφνη ES: adelfa FR: laurierrose IT: oleandro PT: loendro Apocynaceae Variation and Hybridisation It is sometimes difficult to establish whether popula tions are introductions or not, since this species has been cultivated widely and naturalises easily. There are many commercial varieties of oleander, with flowers of different sizes, colours and shapes, which are propa gated vegetatively for ornamental purposes. Pagen (1988) suggests that individuals with very aromatic double flowers are cultivated varieties from the eastern distribution range of the species that were introduced in the 17th century, since the Mediterranean pheno types have simple, nonaromatic flowers. The use of Asiatic material should be avoided in restoration proj ects in Mediterranean environments, where materials of local provenance must always be employed. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from January to February gathering by hand sequence for dehiscent fruits ■ seed weight / kg fruit: 68121 g ■ purity: 9099 % In spite of its pollination problems, this species pro duces a large number of seeds per plant; the number of flowers per individual and seeds per fruit is exceedingly high. This allows a great many seeds to be collected from each plant. There are interannual fluctuations, ■ without treatment Nursery production Sowing season ■ spring, without treatment Vegetative propagation Type of cutting ■ Nerium oleander 88 ■ hardwood semihardwood Conditions ■ Position along the shoot basal or middle terminal 20 ºC Nursery practice ■ ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Number of internodes Size 1520 cm 12 ■ however, and seed production also varies between in dividuals (Herrera, 1991). It is therefore advisable to at tempt to balance maternal contributions and collect from many different individuals in order to increase the genetic variation of the seed lot. Germination under controlled conditions Pregermination treatments T: 4 ºC MC: 48 % ■ airtight container 24 g Germination Viability ■ 8897 % Emergence ■ 710 days after sowing Collecting time DecemberFebruary JulyAugust Auxin concentration none or < 0.5 % none or < 0.5 % References General references Markgraf F (1972) Nerium L. In: Tutin TG et al. (eds). Flora Europaea. Vol 3. Cambridge University Press, Cambridge Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Specific references García España V (1998) Producción de Adelfa. In: Ballester Olmos JF (ed). Producción de Plantas Ornamentales. Escuela Universitaria de Ingeniería Técnica Agrícola de Valencia, Valencia Hatzilazarou S, Ttooulos C, Economou AS, Rifaki N, Ralli P (2003) In vitro and ex vitro rooting and plantlet acclimatiza tion in Nerium oleander. Acta Horticulturae 616:221225 require protected conditions and bed heating is critical (Jiménez, 1978; Ochoa et al., 2004). When using semi woody cuttings, two or three leaves are left on the upper knot; these leaves may be cut in half in order to reduce the transpiration surface (Standardi and Mariani, 1994). Cuttings prepared in the summer should be set out under mist in a substrate that allows good drainage (García Es paña, 1998; Ochoa et al., 2003). In vitro propagation from leaves has been carried out successfully (Santos et al., 1994), with acclimatisation rates of up to 90 % (Roncasaglia et al., 2002). Hatzi lazarou et al. (2003) have performed ex vitro rooting trials using microcuttings. nesis in oleander cuttings. Proceedings of the International Symposium On the Horizons of Using Organic Matter Subs trates in Horticulture 608:101106 Ochoa J, Bañón S, Fernández JA, Franco JA, MartínezSánchez JJ (2004) Rooting medium temperature and carbohydrates af fected oleander rooting. Acta Horticulturae 659:239244 Pagen FJJ (1988) Oleandres. Nerium L. and the oleander cul tivars. Series of revision of Apocynaceae. Part XX. Agricultural University Wageningen Papers 872, The Netherland Pal D, Gupta SK, Afroz N, Singh C (1988) Regeneration of stem cuttings of Nerium oleander Linn. as influenced by indole ace tic acid and planting posture. Advances in Plant Sciences 1:219222 Patil AA, Shirol AM (1991) Studies on rooting of oleander cut tings. South Indian Horticulture 39:4853 Herrera J (1991) The reproductive biology of a riparian Mediterranean shrub, Nerium oleander L. (Apocynaceae). Botanical Journal of the Linnean Society 106:147172 Rocha SC, Quisen RC, Queiroz JA, Zufellato KC (2004) Propa gaçao vegetativa de espirradeira pela tecnica da estaquia. Scientia Agraria 5:7377 Jiménez R (1978) Ensayo de enraizamiento de esquejes de Ne rium oleander variegatum. Informaciones de Floricultura y Plantas Ornamentales 10:1922 Roncasaglia R, Dradi G, Baggio G (2002) Utilizzo della coltura in vitro per l’ottenimento di piante di oleandro (Nerium ole ander L.) ad elevato accestimento. Italus Hortus 9:7375 Kose H, Kostak S (2000) Panasal zakkumun (Nerium oleander L. cv. Variegata) celikle cogaltlmas ve paclobutrazolun buyume ve ciceklenmeye etkileri. Anadolu 10:3142 Ochoa J, Bañón S, Fernández JA, Franco JA, González A (2003) Influence of cutting position and rooting media on rhizoge Santos I, Guimaraes I, Salema R (1994) Somatic embryogene sis and plant regeneration of Nerium oleander. Plant Cell, Tis sue and Organ Culture 37:8386 Standardi A, Mariani A (1994) Indagine sulla propagazione per talea dell’oleandro. Colture Protette 23:7983 89 Nerium oleander Usually, for ornamental plants, oleander is propagated by cuttings. Some authors achieve better results with lignified material obtained in the winter than with ma terial collected in the summer (Jiménez, 1978; Kose and Kostak, 2000; Patil and Shirol, 1991). However, other studies recommend setting out cuttings in the spring, using new material, and advise against doing so in win ter (García España, 1998; Ochoa et al., 2004; Standardi and Mariani, 1994). Either method achieves results of over 90%. Treatment of oleanders with auxins does not improve rooting rates and may even be counterproduc tive (Jiménez, 1978; Pal et al., 1988; Patil and Shirol, 1991; Rocha et al., 2004). Woody cuttings should be 1 to 2 cm in diameter and must be defoliated. These cuttings Pistacia lentiscus L. Distribution and Ecology General distribution: Southwestern and Southeast ern Europe, Western Asia, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Diagnostic traits Pistacia lentiscus is a perennial shrub, 1 to 3 m in height, or sometimes a small tree of up to 6 m. Its leaves are composed of 2 to 12 oblonglanceolate or elliptic leaflets on a winged rachis. It is easily distin guished from other species of the genus that are found Reproductive biology Sex expression ■ dioecy Flowering small reddish or yellowish flowers, clustered in racemes ■ from March to May ■ Anacardiaceae EN: mastic tree EL: σχίνος ES: lentisco FR: lentisque IT: lentisco PT: aroeira Pollination ■ Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Is rael, Libya, Tunisia, Algeria, Morocco The mastic tree grows on all types of soils. It is a ther mophile species that is found in abundance in garrigues and open forests, in areas that are not excessively dry. It resprouts from stumps. in the Mediterranean region and the Middle East (P. at lantica, P. palaestina, P. terebinthus and P. khinjuk) in that it is the only perennial, and it can be included in a separate group on the basis of characterisation using molecular techniques (GolaGoldhirsh et al., 2004). anemophilous Fruiting Ripening ■ ■ blackish globose drupe ■ 47 mm from October to December ■ dispersal by frugivorous vertebrates Pistacia lentiscus 90 Variation and Hybridisation The mastic tree can be distinguished by molecular techniques from the semideciduous hybrid it forms with P. terebinthus (P. × saportae Burnat.). While this hybrid exhibits larger fruits and a narrower leaf rachis wing, the morphological differences are sometimes not very marked, making identification difficult (Werner et al., 2001). It would also seem that the hybrid tends to produce very few fruits, and when it does they are vain or have unviable seeds (Werner et al., 2001; Montser ratMartí and PérezRontomé, 2002). As a precautionary measure it is advisable to use local material for habitat restoration, since genetic varia tions between different provenances have been estab lished using molecular techniques (Werner et al., 2002; Barazani et al., 2003). Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from October to November ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 60325 g ■ purity: 98100% This species produces a great number of flowers and fruits, but the number of fruits with viable seeds is very low, since many flowers do not produce fruit and a large proportion of fruits do not contain seeds (MartínezPalle and Aronne, 2000). Collection of fruits that are white or reddish at maturity should be avoided, as this is a clear indication of embryo abortion or parthenocarpy (Jordano, 1988; 1989). Black drupes should be harvested, since the proportion of seeds in this type of fruit is always higher than in the former type (Verdú and GarcíaFayos, 2002). Additionally, the ■ gentle mechanical scarification Conditions ■ ■ production of fruits with seeds is highly variable within the plants of a single population (MartínezPalle and Aronne, 2000; Verdú and GarcíaFayos, 2002), a bian nual fluctuation in the production of fruits and in the proportion of seedless fruits or fruits with unviable seeds has also been estimated, and the crop may some times be lost (GarcíaFayos, 2001). It has been deter mined that a balanced proportion of male and female plants and densities of over one hundred individuals per hectare promote good yields (Verdú and García Fayos, 1998). Germination under controlled conditions Pregermination treatments 20 ºC Germination Viability ■ Mechanical scarification is not essential, but it speeds up germination time and homogenises emergence. Nursery production Sowing season ■ autumn, without treatment, or spring, with or without treatment Nursery practice forestpot 300 cm3: 1/0 ■ container 3.5 l: 1/1 ■ T: 4 ºC MC: 48 % ■ airtight container 1025 g 7595 % Emergence ■ in spring; 2 to 4 weeks 91 Pistacia lentiscus Tolerance to desiccation: ORTHODOX Vegetative propagation Type of cutting ■ ■ hardwood semihardwood Position along the shoot terminal terminal Number of internodes Size 10 cm 10 cm Mastic, like other species of the Pistacia genus, does not propagate easily using cuttings (Joley and Opitz, 1971). However, if this method is to be employed, the material should be collected from rejuvenated mother plants (Isfendiyaroglu, 2000; Pignati and Crobeddu, 2005; Viola et al., 2004). Collecting time is a key fac tor in the success of cuttings, but the optimum period varies according to different authors. Thus Isfendi yaroglu (2000) and Viola et al. (2004) recommend the months of January and February, respectively, reporting good results (over 75%). Pignati and Crobeddu (2005), for their part, consider the month of July to be better References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Tutin TG (1968) Pistacia L. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Specific references Barazani O, Dudai N, GolanGoldhirsh A (2003) Comparison of Mediterranean Pistacia lentiscus genotypes by random am plified polymorphic DNA, chemical and morphological analy ses. Journal of Chemical Ecology 29:19391952 Barghchi M, Alderson PG (1983) In vitro propagation of Pista cia species. Acta Horticulturae 131:4960 Crobeddu S, Pignatti G (2005) Propagazione per talea di specie mediterranee prove di substrato. Sherwood Foreste ed Alberi Oggi 114:2731 Pistacia lentiscus 92 Fascella G, Airo M, Zizzo G, Ruffoni B (2004) Prime osser vazioni sulla coltivazione in vitro di lentisco (Pistacia lentis cus L.). Italus Hortus 11(4):141143 Collecting time winter summer Auxin concentration 1% 1% than April, since successful results exceed 80% in the summer. Rooting under mist is recommended, with basal heating, using a peat and perlite substrate (1:1) (Crobeddu y Pignati, 2005). In vitro propagation of mastic and other Pistacia species has been performed successfully (Barghchi and Alderson, 1983; Fascella et al., 2004; Gatti et al., 2004; Onay, 2000). If vegetative propagation is desired, this method is an alternative to the difficulties of repro duction from cuttings. Gatti E, Predieri S, Govoni M (2004) Coltura in vitro di piante mediterranee autoctone: cisto, elicriso, lentisco e rosmarino. Italus Hortus 11:135137 GolanGoldhirsh A, Barazani O, Wang ZS, Khadka DK, Saun ders JA, Kostiukovsky V, Rowland LJ (2004) Genetic rela tionships among Mediterranean Pistacia species evaluated by RAPD and AFLP markers. Plant Systematics and Evolution 246:918 Isfendiyaroglu M (2000) Cutting propagation of mastic tree (Pistacia lentiscus var. Chia Duham.). NUCIS Newsletter 9:4244 Joley LE, Opitz KW (1971) Further experiences with propaga tion of Pistacia. Combined Proceedings of the International Plant Propagators Society 21:6776 Jordano P (1988) Polinización y variabilidad de la producción de semillas en Pistacia lentiscus (L.) (Anacardiaceae). Anales del Jardín Botánico de Madrid 45:213231 Jordano P (1989) Predispersal biology of Pistacia lentiscus L. (Anacardiaceae): cumulative effects on seed removal by birds. Oikos 55:375386 MartínezPalle E, Aronne G (2000) Reproductive cycle of Pistacia lentiscus (Anacardiaceae) in Southern Italy. Plant Biosystems 134:365371 MontserratMartí G, PérezRontomé C (2002) Fruit growth dynamics and their effects on the phenological pattern of na tive Pistacia populations in NE Spain. Flora 197:161174 Pignatti G, Crobeddu S (2005) Effects of rejuvenation on cut ting propagation of Mediterranean shrub species. Foresta 2:290295 (online URL: http://www.sisef.it/) Verdú M, GarcíaFayos P (1998) Ecological causes, function and evolution of abortion and parthenocarpy in Pistacia lentiscus L. (Anacardiaceae). Canadian Journal of Botany 76:134141 Verdú M, GarcíaFayos P (2002) Ecología reproductiva de Pis tacia lentiscus L. (Anacardiaceae): un anacronismo evolutivo en el matorral mediterráneo. Revista Chilena de Historia Na tural 75:5765 Viola F, Forleo LR, Cocozza MA (2004) Propagazione agamica di alcune specie della macchia mediterranea. Italus Hortus 11:186190 Werner O, SánchezGómez P, CarriónVilches MA, Guerra J (2002) Evaluation of genetic diversity in Pistacia lentiscus L. (Anacardiaceae) from the southern Iberian Peninsula and North Africa using RAPD assay. Implications for reafforesta tion policy. Israel Journal of Plant Science 51:1118 Werner O, SánchezGómez P, Guerra J, Martínez JF (2001) Identification of Pistacia x saportae Burnat. (Anacardiaceae) by RAPD analysis and morphological characters. Scientia Hor ticulturae 91:179186 93 Pistacia lentiscus Onay A (2000) Micropropagation of pistachio from mature trees. Plant Cell Tissue and Organ Culture 60:159162 Platanus orientalis L. Distribution and Ecology General distribution: Southeastern Europe, Western Asia Mediterranean region: Italy (incl. Sicilia), Montenegro, Albania, Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel Diagnostic traits Platanus orientalis is a deciduous tree that reaches a height of 30 m, with rhytidome that peels off in sheets. Leaves exhibit 3 to 5 dentate lobes that are greater in length than in width. Female flower heads are normally Reproductive biology Sex expression ■ monoecy Flowering small flowers, clustered in heads ■ from March to May ■ Platanaceae EN: oriental plane tree EL: πλάτανος η ανατολική ES: plátano oriental FR: platane d’Orient IT: platano orientale PT: plátanooriental Pollination ■ The oriental plane grows in humid forests, valley bot toms and riparian areas. arranged in groups of three to six on a long peduncle. Fruits have a more or less pyramidal or wide wedge shaped apex. anemophilous Fruiting Ripening ■ ■ clavate achenes in globose infructescence from October to November, persisting on the tree until the following spring ■ dispersal by wind Platanus orientalis 94 Variation and Hybridisation Platanus acerifolia (Aiton) Willd. is very common in Western Europe as an ornamental species. Popularly known as London plane or hybrid plane, its leaf char acteristics are halfway between those of P. orientalis and P. occidentalis L., with deep lobes that are wider and less deep than those of Platanus orientalis, and its infructescences are arranged in groups of two. Tests using molecular techniques have confirmed the hybrid origin of this species, with P. orientalis possibly acting as the female parental species (Besnard et al., 2002). Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ sequence for dehis cent fruits ■ seed weight / kg fruit: 500600 g (P. occidentalis) ■ purity: 85 % Germination under controlled conditions Pregermination treatments ■ prechilling (612 weeks) Conditions ■ 20 ºC to 25 ºC Pregermination treatments are not strictly required for oriental plane seeds, but prechilling accelerates and Nursery production Sowing season ■ winter, without treatment, or spring, with treatment ■ Germination Viability ■ 3040 % homogenises germination. Nursery practice ■ T: 7 ºC a 4 ºC MC: 48 % ■ airtight container 24 g bareroot: circumference up to 810 cm Emergence ■ in spring, complete in one month 95 Platanus orientalis from late autumn to winter ■ gathering by hand, using longhandled tools, or collecting naturally fallen material Vegetative propagation Type of cutting ■ ■ hardwood semihardwood Position along the shoot basal basal Number of internodes Size 25 cm 10 cm Cuttings from the basal area should be used when the ortet is an adult plant (Nahal and Rahme, 1990; Vla chov, 1988), whereas if it is a young plant, the part of the stem from which the cutting is obtained does not influence rooting capacity as much. Rejuvenation prun ing considerably improves the results (Vlachov, 1988). To propagate adult individuals, Arene et al. (2001) rec ommend using twoyearold material or hardwood mallet cuttings, making the upper cut just above the first bud. According to Vlachov (1998), better results are obtained from hardwood cuttings in winter (80 100%) than from semihardwood material in summer (3060%). Cutting propagation in winter requires pro References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Piotto B, Di Noi A (eds.) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Tutin TG (1993) Platanus L. In: Tutin TG et al. (eds). Flora Eu ropaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Yaltirik F (1982) Platanus L. In: Davis PH (ed). Flora of Turkey and East Aegean Islands. Vol 7. University Press, Edinburgh Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Arene L, Cadic A, Djulbic M, Gros A, Renoux A (2001) Multi plication du platane par bouturage hivernal sur couche et mi crobouturage in vitro. PHM Revue Horticole 423:2326 Platanus orientalis 96 Besnard G, Tagmount A, Baradat P, Vigouroux A, Bervillé A (2002) Molecular approach of genetic affinities between wild and ornamental Platanus. Euphytica 126:401–412 Collecting time DecemberJanuary August Auxin concentration none none tected conditions (Grolli et al., 2005; Nahal and Rahme, 1990; Vlachov, 1988). Treatment with auxin can have negative effects, particularly if combined with bed heating (Grolli et al., 2005; Panetsos et al., 1994; Vla chov, 1988). Micropropagation of P. orientalis appears to be possi ble as P. acerifolia has been multiplied in vitro (Grolli et al., 2004; Liu and Bao, 2003). Likewise, P. orientalis has regenerated satisfactorily from latent buds (Arene et al., 2001) and from calluses that have formed on leaf explants (Qiang et al., 2003). Grolli PR, Morini S, Loreti F (2004) The micropropagation of Platanus acerifolia Willd. Advances in Horticultural Science 18:121126 Grolli PR, Morini S, Loreti F (2005) Propagation of Platanus acerifolia Willd. by cutting. Journal of Horticultural Science and Biotechnology 80:705710 Liu G, Bao M (2003) Adventitious shoot regeneration from in vitro cultured leaves of London plane tree (Platanus acerifo lia Willd.). Plant Cell Reports 21:640644 Nahal I, Rahme A (1990) Le platane d’Orient (Platanus orien talis L.) dans la region du Proche Orient. Forêt Mediterrane ènne 12:115124 Panetsos KP, Scaltsoyiannes AV, Alizoti PG (1994) Vegetative propagation of Platanus orientalis x P. occidentalis F1 hybrids by stem cuttings. Forest Genetics: International Journal of Fo rest Genetics 1:125130 Qiang FG, Ping JJ, Qing JY, Feng L (2003) In vitro efficient plant regeneration with Platanus orientalis L. leaves as explants. Acta Horticulturae Sinica 30:236238 Vlachov DD (1988) Vegetative propagation of sp. Platanus L. through rooting of cuttings. Acta Horticulturae 226:375378 Salicaceae Populus alba L. EN: abele, white poplar EL: λεύκη η λεύκη ES: álamo blanco, chopo blanco FR: peuplier blanc, peuplier de Hollande IT: pioppo bianco, gattice PT: álamobranco, choupobranco Distribution and Ecology General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Caucasus, Western and Middle Asia, Siberia, China, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Turkey, Syria, Lebanon, Libya, Tunisia, Algeria, Morocco The white poplar is a sunloving species that grows on neutral or alkaline substrata and can withstand heavy soils and a certain level of salinity. It gathers in dense stands or grows scattered in low, sometimes swampy riverine areas. In cool environments it may grow in mixed poplar groves with Populus nigra, while in coastal or warmer areas it becomes dominant because it is more thermophile. Diagnostic traits The traits by which P. alba, P. tremula and the spontaneous hybrid of these two species (P. x canescens Sm.) can be distinguished are detailed in a table in an Appendix. Sex expression ■ dioecy Flowering ■ ■ inconspicuous flowers, clustered in pendulous catkins from February to April, before leaf development Pollination ■ anemophilous Fruiting Ripening ■ ■ ■ oblongconic capsule about 4 mm ■ from March to June dispersal by wind 97 Populus alba Reproductive biology Variation and Hybridisation The white poplar is widely used for ornamental pur poses because of its plasticity and its attractive white bark. P. alba cv. ‘Roumi’, commonly known as “Bol leana”, is used a great deal because of its uniform arrangement of branches, growing from the very base of the tree, and its pyramidal shape. Materials from cultivated varieties such as this should be restricted to urban gardens and must not be used for riparian restorations. Preliminary analysis of Spanish populations of Populus alba by molecular techniques reveals a strong geo graphic pattern of genetic variation by hydrological basins (S. GonzálezMartínez, pers. com.). Conse quently, it is advisable to limit the use of reproductive materials to the river basin of origin and to avoid trans ferring materials from one basin to another. The enormous facility with which white poplars re sprout from the roots could lead to a situation where populations of these trees exhibit a low level of genetic variation, as marker studies have shown in some Sar dinian populations, which reveal few genotypes and a tendency to spatial grouping (Zappelli et al., 2005); this clonal gathering is also found in Spanish populations (S. GonzálezMartínez, pers. com). Consequently, when collecting vegetative material of this species it is ad visable to leave a distance of several metres between ortets or groups of suckers and collect relatively few materials from each individual or group of individuals. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight ■ ■ ■ ■ from March to June using longhandled tools or collecting naturally fallen material sequence for dehiscent fruits ■ purity: 4050 % Collection must begin when the capsules start to open; this requires careful field supervision, since seeds are quickly scattered by the wind. Keeping the fruitpro ducing catkins at room temperature for 3 to 5 days al lows the capsules to open up fully and permits seed dehiscence. It is not necessary to remove the tufts of hair that cover the seeds, although doing so does make handling easier. Separation can be performed using finemesh sieves and compressed air. Cleaning and preparation should be carried out in less than a week, ■ without treatment Conditions ■ 0.10.6 g T: 18 ºC MC: 68 % ■ airtight container ■ ■ since the seeds lose their viability rapidly if kept in nor mal temperature and moisture conditions. Seeds with a moisture content of 5 % to 8 % may be preserved for a couple of years in airtight containers at 4 ºC to 5 ºC; for longer periods, temperatures below 0 ºC are recommended. Seeds that have been preserved for a long time must be rehydrated gradually (using moist air, for instance), as they can be damaged by excessi vely rapid moisture uptake. Germination under controlled conditions Pregermination treatments Storage 20 ºC to 25 ºC Germination Viability ■ 8595 % Populus alba 98 Sowing season ■ spring, without treatment, immediately after collecting Nursery practice bareroot: about 3,000 seeds/m2; circumference up to 68 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ The seeds should not be covered or pressed into the substrate after sowing. The seedlings are very delicate and are susceptible to drought during the first month. When plants are produced in containers, it is possible Vegetative propagation Type of cutting ■ ■ hardwood root Position along the shoot basal The possibility of successfully reproducing white poplar using cuttings largely depends on the ortet. Therefore, if working with a large number of clones, a relatively high percentage of losses should be expected (Sekawin, 1975). If working with material from individuals which are difficult to root, results may be improved by using any of the following methods: cut the material just below a knot; submerge the basal end of the cuttings in water, maintaining a temperature of 16 °C and total darkness until the roots begin to emerge (Phipps et al., 1983); plant cuttings with bed heating at 20 °C; or col lect material from parent stocks established for this purpose. Whichever the method, it requires vigorous material from the bottom of the crown or from new References General references Amaral Franco J do (1993) Populus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin ■ 1224 h after sowing to sow in small pots (volume up to 7075 cm3). Once the seedlings have become established in these smaller cells, they can be removed and transplanted into the growth containers. Number of internodes Size 10 15 cm 5 10 cm Emergence Collecting time FebruaryMarch early spring Auxin concentration none or 0.5 % none shoots. The cuttings should be between 8 and 20 mm in diameter (Phipps and Netzer, 1981; Sabatti et al., 2001). Another possible propagation method is derived from the natural ability of this species to sprout from the root. Root segments may be used for rooting and direct plant production or as a source of green shoots for use as cuttings. In vitro propagation is possible and has been carried out successfully using catkins (Good et al., 1992, 2001), stem segments (Sellman et al., 1989) and axillary leaf buds (Bagnaresi and Minotto, 1982). Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Soriano C (1993) Populus L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid 99 Populus alba Nursery production Specific references Bagnaresi U, Minotta G (1982) Ricerche sulla micropropaga zione di pioppi della Sez. Leuce. Annali, Accademia Italiana di Scienze Forestali 31:239254 Bueno MA, Astorga R, Manzanera JA (1992) Micropropagación de Populus alba ‘Siberia Extremeña’ a partir de amentos. Inves tigación Agraria, Sistemas y Recursos Forestales 1:163171 Bueno MA, Manzanera JA, Grau JM, Sánchez N, Gómez A (2001) Propagación in vitro de Populus tremula L. y Populus alba L. In: Actas del I Simposio del Chopo, 911 mayo 2001, Zamora Phipps HM, Hansen EA, Fege AS (1983) Preplant soaking of dor mant Populus hardwood cuttings. Research Paper NC241. USDA Forest Service, North Central Forest Experiment Station, St Paul Phipps HM, Netzer DA (1981) The influence of collection time and storage temperature on Populus hardwood cutting deve lopment. Tree Planters’ Notes 32:3336 Sabatti M, Nardin F, Olivero M, Alasia F, ScarasciaMugnozza G (2001) Propagazione vegetativa del pioppo bianco (Populus alba) mediante talee legnose: variabilità genetica e modalità di trattamento del materiale. Alberi e Foreste per il Nuovo Mi llennio. In: Atti del III Congresso Nazional S.I.S.E.F, 1518 Ottobre 2001, Viterbo Sekawin M (1975) La Génétique du Populus alba L. Annales Forestales 6:157189 Sellmer JC, McCown BH, Haissi BE (1989) Shoot culture dyna mics of six Populus clones. Tree Physiology 5:219227 Zapelli I, Fossati T, Patrignani G, Brundu G, Camarda I, Sala F, Castiglione S (2005) AFLPs to assess the controversial status of Populus alba L. of Sardinia. International workshop: The role of biotechnology for the characterisation and conservation of crop, forestry, animal and fishery genetic resources, 57 March, Turin, Italy (online URL http://www.fao.org/biotech/to rino05.htm) Populus alba 100 Distribución general: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern and Middle Asia, Siberia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Tunisia, Algeria, Morocco Diagnostic traits P. nigra may easily be confused with genotypes origi nated by its hybridisation with P. deltoides, which have been widely cultivated. Traits that allow these two Reproductive biology ■ dioecy Flowering ■ ■ inconspicuous flo wers, clustered in pendulous catkins from February to April, before leaf development Pollination ■ The black poplar is a sunloving species that pioneers riverside forests and prefers alkaline to neutral reac tion soils. It cannot withstand swampy ground for pro longed periods of time. It grows individually or in the form of small stands along the banks of rivers. species and their hybrid (P. x canadensis) to be distin guished are shown in a table in an Appendix. anemophilous Fruiting Ripening ■ ■ ■ ellipsoidal capsule 79 mm ■ from March to June dispersal by wind 101 Populus nigra Distribution and Ecology Sex expression Populus nigra L. EN: black poplar EL: λεύκη η μαύρη ES: chopo FR: peuplier noir IT: pioppo nero PT: choupo negro Salicaceae Variation and Hybridisation Three subspecies are described: P. nigra subsp. nigra, which is found in central and eastern Europe and is characterised by having glabrous twigs and leaves; P. nigra subsp. betulifolia (Pursh), from western Europe, with pubescent twigs and young leaves and noncau date leaves on short shoots; and P. nigra subsp. caud ina, found in the Mediterranean region, which has hispid twigs and young leaves and caudate leaves on short shoots. Several varieties of poplar have been defined. Some of them come from cultivated clones; such as the Lom bardy poplar (P. nigra var. italica Münchh), a fastigiate variety that may result from one or more male geno types and has been spread widely through Europe since the 18th century. Use of this material of uncertain ori gin must be avoided in favour of autochthonous sub species and genotypes. Although the risk of backcrossing of Populus nigra with commercial clones of P. × canadensis seems quite un likely in some populations, due to differences in phe nology (Gebhardt et al., 2001; Fossati et al., 2003), overlapping floral phenology has been observed in oth ers (Vander Broeck et al., 2003). The possibility of in trogression of EuroAmerican hybrids with the autochthonous species has been confirmed in differ ent populations using molecular techniques (Vanden Broeck et al., 2004; Pospíšková and Šálková, 2006); these studies have shown that small isolated popula tions of P. nigra surrounded by more or less extensive commercial plantations are especially vulnerable (Van den Broeck et al., 2005). Introgression of P. trichocarpa genes (Lefèvre et al., 2002) is also possible. Collection of seeds in this type of situation should be avoided in favour of vegetative multiplication, in such a way as to ensure the taxonomical identity of the propagated ma terial and favour the use and preservation of the au tochthonous species. The study of spatial variations of genetic diversity seems to show that there are no great differences be tween regions but there are differences between pop ulations within the same region (Legionnet and Lefèvre, 1996); these differences between populations that are near to each other would seem to indicate limited ge netic flow (Legionnet and Lefèvre, 1996; Imbert and Lefèvre, 2003; Pospíšková and Šálková, 2006), in spite of the fact that the pollen and seeds of this species are dispersed by the wind. However, the highest levels of diversity seem to appear at population level, even in not very extensive populations, as seed propagation predominates over vegetative propagation (Arens et al., 1998; Pospíšková and Šálková, 2006). Considering the results of genetic studies, a seedcollection unit might cover scattered populations and individuals which are not divided by topographical barriers that reduce pollen flow. It should be borne in mind that this species also repro duces naturally by means of vegetative propagation and that there may therefore be ramets of the same clone with varying degrees of spatial aggregation within a given stand or even at a distance of several kilometres. The incidence of such natural vegetative re production seems to vary a great deal (Legionnet et al. 1997; Arens et al., 1998; Barsoum et al., 2004), de pending on the past history of smallscale spatial dis turbances and on available resources in terms of the number and age of trees. It is thus difficult to establish simple recommendations to ensure the collection of different clones. In these cases, molecularmarker char acterisation should be used to differentiate genotypes and guarantee a certain level of genetic variation using a wellbalanced mixture of clones. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ Populus nigra 102 from March to June using longhandled tools or naturally fallen material sequence for dehiscent fruits ■ purity: 4050 % 0.91 g T: 18 ºC MC: 68 % ■ airtight container ■ since the seeds lose their viability rapidly if kept in nor mal temperature and moisture conditions. Seeds with a moisture content of 5 % to 8 % may be preserved for a couple of years in airtight containers at 4 ºC to 5 ºC; for longer periods, temperatures below 0 ºC are rec ommended. Seeds that have been preserved for a long time must be rehydrated gradually (using damp air, for instance), as they can be damaged by excessively rapid moisture uptake. Germination under controlled conditions Pregermination treatments ■ without treatment ■ Nursery production Sowing season ■ Conditions spring, without treatment, immediately after collecting 20 ºC to 25 ºC Nursery practice Type of cutting ■ hardwood Position along the shoot indifferent ■ bareroot: circumference up to 68 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 Populus nigra is very easily propagated by cuttings (Da genbach, 1997). Material collected at practically any time of the year will grow roots, although hardwood cuttings are the best material to use (Blake and Atkin son, 1986; Gunes, 2000). It is advisable to use material taken from sets or oneyearold shoots with a diame ter of 12 to 20 mm (Holzberg, 1999). ■ 1224 h after sowing to sow in small pots (volume up to 7075 cm3). Once the seedlings have become established in these smaller cells, they can be removed and transplanted into the growth containers. Number of internodes Size 20 30 cm 8595 % Emergence ■ The seeds should not be covered or pressed into the substrate after sowing. The seedlings are very delicate, and are susceptible to drought during the first month. When plants are produced in containers, it is possible Vegetative propagation Germination Viability Collecting time February Auxin concentration none In vitro regeneration of this species is also possible; it has been successfully achieved with axillary and apical buds and with stem segments (Kapusta and Skibinska, 1985; Naujoks and Wuhlisch, 2004; Noël et al., 2002). 103 Populus nigra Collection must begin when the capsules start to open; this requires careful field supervision, since seeds are quickly scattered by the wind. Keeping the fruitpro ducing catkins at room temperature for 3 to 5 days al lows capsules to open up fully and permits seed dehiscence. It is not necessary to remove the tufts of hair that cover the seeds, although doing so does make handling easier. Separation can be performed using finemesh sieves and compressed air. Cleaning and preparation should be carried out in less than a week, References General references Amaral Franco J do (1993) Populus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Soriano C (1993) Populus L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid Specific references Arens P, Coops H, Vosman B (1998) Molecular genetic analy sis of black poplar (Populus nigra L.) along Ditch rivers. Mo lecular Ecology 7:1118 Barsoum N, Muller E, Skot L (2004) Variations in levels of clon ality among Populus nigra L. stands of different ages. Evolu tionary Ecology 18:601624 Blake TJ, Atkinson SM (1986) The physiological role of absicic acid in the rooting of poplar and aspen stump sprouts. Physio logia Plantarum 67:638643 Dagenbach H (1997) Praktische Vorschlage zur Nachzucht der einheimischen Schwarzpappel (Populus nigra L.). Holzzucht 51:2326 Fossati T, Grassi F, Sala F, Castiglione S (2003) Molecular analysis of natural populations of Populus nigra L. intermin gled with cultivated hybrids. Molecular Ecology 12:2033 Gebhardt K, Pohl A, Vornam B (2001) Genetic inventory of black poplar populations in the Upper Rhine floodplains: con clusions for conservation of an endangered plant species. In: van Dam BC and Bordács S (eds). Proceedings of the Interna tional Symposium: Genetic diversity in river populations of European Black Poplar. Szeksárd, Hungary, 1620 May 2001. Verlag C. Nyomda, Budapest Gunes T (2000) Peroxidase and IAAoxidase activities during rooting in cuttings of three poplar species. Turkish Journal of Botany 24:97101 Populus nigra 104 Holzberg H (1999) Propagation strategies of Populus nigra under natural environmental conditions and artificial propa gation in the nursery. Holzzucht 52:1416 Imbert E, Lefèvre F (2003) Dispersal and gene flow of Populus nigra (Salicaceae) along a dynamic river system. Journal of Ecology 91:447456 Kapusta J, Skibinska A (1985) Induction of morphogenesis and regeneration in the callus of Populus alba L. and P. nigra L. Journal of Tree Sciences 4:3438 Lefèvre F, Bordács S, Cottrell J, Gebhardt K, Smudlers MJM, Vanden Broeck A, Vornam B, Van Dam BC (2002) Recommen dations for riparia ecosystem management based on the gen eral frame defined in EUFORGEN and results from EUROPOP (2002). In: van Dam B, Bordács S (eds). Genetic diversity in river populations of European Black Poplar. Csiszár Nyomda, Budapest Legionnet A, FaivreRampant P, Villar M, Lefèvre F (1997) Sex ual and asexual reproduction in natural stands of Populus nigra. Botanical Acta 110:257263 Legionnet A, Lefèvre F (1996) Genetic variation of the ripar ian pioneer tree species Pinus nigra L. I. Study of population structure based on isozymes. Heredity 77:629637 Naujoks G, Wühlisch G von (2004) Micropropagation of Po pulus nigra L.: a potential contribution to gene conservation and tree improvement. In: Koskela J, de Vries SMG, Kajba D and von Wühlisch G (comp). Populus nigra Network, Report of seventh (25–27 October 2001, Osijek, Croatia) and eighth me etings (22–24 May 2003, Treppeln, Germany). International Plant Genetic Resources Institute, Rome Noël N, Leplé JC, Pilate G (2002) Optimization of in vitro mi cropropagation and regeneration for Populus x interamericana and Populus x euramericana hybrids (P. deltoides, P. tricho carpa, and P. nigra). Plant Cell Reports 20:11501155 Pospíšková M, Šálková I (2006) Population structure and parentage analysis of black poplar along the Moravia River. Canadian Journal of Forest Research 36:10671076 Vanden Broeck A, Cox K, Quataert P, Van Bockstaele E, Van Slycken J (2003) Flowering phenology of Populus nigra L., P. nigra cv. italica and P. x canadensis Moench. and the poten tial for natural hybridisation in Belgium. Silvae Genetica 52:280283 Vanden Broeck A, Storme V, Cottrell JE, Bockstaele E, Quataert P, Van Slycken J (2004) Gene flow between cultivated poplars and native black poplar (Populus nigra L.): a case study along the river Meuse on the DutchBelgian border. Forest Ecology and Management 197:307310 Vanden Broeck A, Villa M, Van Bockstaele E, Van Slycken J (2005) Natural hybridization between cultivated poplars and their wild relatives: evidence and consequences for native poplar populations. Annals of Forest Science 62:601613 Salicaceae Populus tremula L. EN: European aspen EL: λεύκη η τρέμουσα ES: álamo temblón FR: peuplier tremble IT: pioppo tremolo PT: choupotremedor Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern and Middle Asia, Siberia, Mongolia, China, North ern Africa Mediterranean region: Spain, France (incl. Corse), Italy (incl. Sardegna), Croatia, BosniaHerzegovina, Montene gro, Albania, Greece, Turkey, Syria, Lebanon, Algeria European aspen is a pioneer species that grows in a wide range of climatic conditions on fertile, preferably neutral soils, although it can withstand alkaline reac tion substrates. Its superficial root system allows it to grow on shallow but moist soils. P. tremula does not usually occur in very large populations. It may be found as a pioneer in open, treeless areas or in coniferous, leafy or mixed forests. In the Mediterranean region it is associated with soils with a phreatic water supply and grows on slopes, valley bottoms and the banks of wa tercourses, where it may mix with other riparian ele ments. This taxon is useful in hydrological restoration projects in moist Mediterranean mountain areas. Diagnostic traits The diagnostic traits that make it possible to distin guish this species from Populus alba and their hybrid, P. x canescens, are shown in an Appendix. Sex expression ■ dioecy Flowering inconspicuous flowers, clustered in pendulous catkins ■ from February to April, before leaf development ■ Pollination ■ anemophilous Fruiting Ripening ■ ■ ovate capsule, granular ■ 34 mm from April to June ■ dispersal by wind 105 Populus tremula Reproductive biology Variation and Hybridisation P. tremula has a strong ability to sprout from the root, so within a single stand some individuals may belong to the same genotype, as different genetic studies have confirmed. In addition, it would seem that there is a tendency towards aggregation in the spatial distribu tion of clones (Suvanto and LatvaKarjanma, 2005; LatvaKarjanma, 2006). However, a great deal of ge netic variation between relatively close populations has been observed (Sierra de Grado et al., 2003). In order to increase the genetic variation within batches of repro ductive material, it is advisable to collect such material from several populations that are more or less near to each other; within the populations themselves, mate rial should be collected from individuals that are dis tant from each other or have differently shaped leaves, since this trait seems to be a good criterion for dis crimination between genotypes (López de Heredia et al., 2004). If material is collected for vegetative prop agation, the sex of the ortet must be considered, both male and female material should be produced and the new plantation should be managed in such a way as to promote regeneration through seeds. P. tremula hybridises naturally with P. alba, producing P x canescens (Aiton) Sm.; introgression in this case is unidirectional and the aspen acts as a male parental (Lexer et al., 2005). P. x canescens grows on river banks and in ravines, where it shares its habitat with P. alba, or in somewhat cooler environments at higher alti tudes. Its morphology varies greatly, depending on the degree of backcrossing, and individuals exhibit a gra dation of traits that may be closer to either P. alba or P. tremula. Classification difficulties may be solved using molecular markers (Fossati et al., 2004). P. x canescens is a dioecious species and its seeds have a very low level of viability. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from April to June using longhandled tools or naturally fallen material sequence for dehiscent fruits ■ purity: 4050 % The most common pattern of P. tremula is an imbal ance of the maletofemale ratio within stands (Wor rell, 1995; Worrell et al., 1999), which can lead to limited seed production. Collection must begin when the capsules start to open; this requires careful field supervision, since seeds are quickly scattered by the wind. Keeping fruitproducing catkins at room temperature for 3 to 5 days allows cap sules to open up fully and permits seed dehiscence. It is not necessary to remove the tufts of hair that cover the seeds, although doing so does make handling eas 0.060.16 g T: 18 ºC HC: 68 % ■ airtight container ■ ier. Separation can be performed using finemesh sieves and compressed air. Cleaning and preparation should be carried out in less than a week, since the seeds lose their viability rapidly if kept in normal temperature and moisture conditions. Seeds with a moisture content of 5 % to 8 % may be preserved for a couple of years in airtight containers at 4 ºC to 5 ºC; for longer periods, it is advisable to store them at 20 ºC (Simak, 1982). Seeds that have been preserved for a long time must be rehydrated gradually (using moist air, for instance), as they can be damaged by excessively rapid moisture uptake. Populus tremula 106 Germination under controlled conditions ■ without treatment ■ Nursery production Sowing season ■ Conditions spring, without treatment, immediately after collecting 20 ºC to 25 ºC Nursery practice Type of cutting ■ ■ root softwood Position along the shoot ■ 9095 % Emergence bareroot: 1020 g/m2; cir ■ 1224 h after sowing cumference up to 68 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ The seeds should not be covered or pressed into the substrate after sowing. Seedlings are very delicate and are susceptible to drought during the first month. When plants are produced in containers, it is possible Vegetative propagation Germination Viability to sow in small pots (volume up to 7075 cm3). Once the seedlings have become established in these smaller cells, they can be removed and transplanted into the growth containers. Number of internodes Size 40 cm 2 European aspen and its hybrids are difficult to repro duce using cuttings from branches, since the aerial or gans do not induce root primordia (Blake and Atkinson, 1986; Wyckoff and Zasada, 2003). The more common method of achieving vegetative propagation in European aspen is by means of root cut tings. During the winter, root cuttings are buried hori zontally in boxes with moist sand. Once the shoots are about 5 cm in length, they are cut, treated with indol butyric acid in powder form, planted in a substrate of peat and vermiculite (1:1) and held in a tunnel in a mist atmosphere. Once roots are formed, the plants are gradually hardened off. Later, they are transferred to cultivation beds or, preferably, to containers (Moon Collecting time winter spring or summer Auxin concentration none 0.5 % 2003; Trees for life, 2004). Haapala et al. (2004) sug gest propagating from softwood cuttings approxi mately 23 mm in diameter, obtained from parent plants rejuvenated by means of in vitro cultivation and rooted in forest pots under conditions of high environ mental humidity. Ahuja (1983) describes a method for fast microprop agation of Populus tremula. Cultivation is started with apical or axillary buds in a medium with cytoquinines. Later, the microstems are rooted in a medium with auxins or directly in a substrate under controlled cli mate conditions. This second option reduces the cost considerably. 107 Populus tremula Pregermination treatments References General references Amaral Franco J do (1993) Populus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Soriano C (1993) Populus L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid Specific references Ahuja MR (1983) Somatic cell differentiation and rapid clonal propagation of aspen. Silvae Genetica 32:131135 Blake TJ, Atkinson SM (1986) The physiological role of absicic acid in the rooting of poplar and aspen stump sprouts. Physio logia Plantarum 67:638643 Fossati T, Patrignani G, Zapelli I, Sabatti M, Sala F, Castiglione S (2004) Development of molecular markers to assess the level of introgression of Populus tremula into P. alba natural popu lations. Plant Breeding 123:382385 Haapala T, Pakkanen A, Pulkkinen P (2004) Variation in survi val and growth of cuttings in two clonal propagation methods for hybrid aspen (Populus tremula x P. tremuloides). Forest Ecology and Management 193:345354 LatvaKarjanmaa T (2006) Reproduction and population struc ture in European aspen. Ph.D Thesis. University of Helsinki, Finland Lexer C, Fay MF, Joseph JA, Nica MS, Heinze B (2005) Barrier to gene flow between two ecologically divergent Populus species, P. alba (white poplar) and P. tremula (European aspen): the role of ecology and life history in gene introgression. Mo lecular Ecology 14:1045–1057 López de Heredia U, Sierra de Grado R, Cristóbal MD, Martínez Zurimendi P, Pando V, Martín MT (2004) A comparison of isozyme and morphological markers to assess the within pop ulation variation in small populations of European aspen (Pop ulus tremula L.) in Spain. Silvae Genetica 53:227233 Luna T (2003) Propagation protocol for aspen using root cut tings. Native Plants Journal 4:129131 Sierra de Grado R, Martínez Zurimendi P, López de Heredia La rrea U (2003) Reproducción sexual y diversidad genética de Populus tremula. In: Sierra de Grado R (coord). El álamo tem blón (Populus tremula L.). Bases para su cultivo, gestión y con servación. Ediciones MundiPrensa, Madrid Simak M (1982) Germination and storage of Salix caprea L. and Populus tremula L. seeds. In: Wang BSP, Pitel JA (eds). Proceed ings of the international symposium on forest tree seed storage. IUFRO Canadian Forestry Service, Chalk River: 142160 Suvanto LI, LatvaKarjanmaa TB (2005) Clone identification and clonal structure of the European aspen (Populus tremula). Molecular Ecology 14:28512860 Trees for life (2004) The propagation of aspen from root cut tings. (online URL http://www.treesforlife.org.uk/tfl.aspen_propagation.html) Worrell R (1995) European aspen (Populus tremula L.): a review with particular reference to Scotland I. Distribution, ecology and genetic variation. Forestry 68:93105 Worrell R, Gordon AG, Lee RS, McInroy A (1999) Flowering and seed production of aspen in Scotland during a heavy seed year. Forestry 72:2734 Wyckoff GW, Zasada JC (2003) Populus L. In: Bonner FT (ed). Woody Plant Seed Manual. USDA Forest Service. Reforesta tion, Nurseries and Genetics Resources, Connecticut. (online URL http://www.nsl.fs.fed.us/wpsm/Populus.pdf) Populus tremula 108 Prunus mahaleb L. EN: mahaleb cherry, Saint Lucie cherry EL: αγριοκέρασο αχαλέμπιο; κεράσι μικρόκαρπο ES: cerezo de Santa Lucía, cerecino FR: bois de SainteLucie, cerisier de SainteLucie IT: ciliegio di Santa Lucia, ciliegio canino PT: cerejeiradeSanta Lúcia, cerejeira mahaleb Distribution and Ecology General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Caucasus, Western and Middle Asia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Lebanon, Morocco Diagnostic traits Prunus mahaleb is a deciduous shrub that usually reaches a height of 2.5 m, although it can sometimes grow higher. Its leaves are broadly ovate or subcordate, sometimes suborbicular, up to 7 cm long, glabrous Reproductive biology Sex expression ■ gynodioecy Flowering white flowers, clustered in short corymbiform, racemiform cymes ■ from May to June ■ Pollination ■ The St. Lucie cherry prefers calcareous, alkaline to neu tral soils and cool, moist environments. It is found as scattered individuals or in small groups in thorny thick ets, humid forest glades, next to streams and ravines, and on cliffs and rocky, shady slopes. above and glabrous o slightly pubescent beneath. Its flowers have glabrous ovaries and are arranged in groups of three to eleven in short corymbiform, racemi form cymes. entomophilous Fruiting Ripening ■ ■ ■ glossy black drupe 610 mm from June to September ■ dispersal by frugivorous vertebrates 109 Prunus mahaleb Rosaceae Variation and Hybridisation Functionally female individuals seem to have greater advantages than hermaphrodites as regards traits as sociated with fertility and tend to produce more fruit and heavier seeds, possibly due to higher levels of crossfertilisation, especially in good fruitproducing years (Jordano, 1993). Their progeny also have a higher degree of genetic variation due to the absence of self fertilisation and the contribution of a greater number of parents to pollination, particularly in more or less isolated individuals and lowdensity populations (Gar cía et al., 2005). The number of fruits produced varies depending on genotype and plant size. Genetic studies show that the seeds of this species are efficiently spread by frugivores, which helps to preserve high levels of genetic diversity within populations (Jor dano and Godoy, 2000). However, it would seem that the nonrandom behaviour of pollinators and dispersers might give the gene flow a certain spatialdistribution pattern, thus producing genetic structuring within a single population or between geographically close pop ulations (García et al., 2007). In particular, seedmigra tion distances vary depending on the frugivorous species that acts as a carrier (Jordano et al., 2007), but dispersal within short distances from the mother tree seems to be the most frequent pattern (Godoy and Jordano, 2001). All these factors make it advisable for fruit collection not to concentrate solely on individuals of greater size but to cover a high number of individuals, which should be somewhat distant from each other, and to include a high proportion of functionally female trees. In addi tion, in order to ensure that batches will have a rea sonable level of genetic variation, it is advisable to collect material from different more or less neighbour ing populations within a region of provenance. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight ■ ■ ■ ■ from July to August gatherIng by hand or beating branches sequence for fleshy fruits ■ seed weight / kg fruit: 130265 g ■ purity: 100 % Fruits must be fully mature when collected, but to pre vent losses by birds, harvesting should not be delayed. 4893 g Storage T: 5 ºC to 4 ºC MC: 48 % ■ airtight container ■ ■ Prunus mahaleb 110 Germination under controlled conditions ■ prechilling (816 weeks) Conditions ■ ■ 21 / 16 ºC light Like those of other Prunus species, the seeds of the St. Lucie cherry have dormant embryos and thus require prolonged cold stratification. They may enter a second period of dormancy (secondary dormancy) if this cold stage is interrupted by drying at room temperature (Baskin and Baskin, 1998) or by a rise in temperature. However, induction of secondary dormancy by raising the temperature is used in Prunus avium to achieve better germination percentages. Suszka et al. (1994) recommend applying a stratification system that in Nursery production Sowing season ■ late winter or early spring, with treatment Vegetative propagation Type of cutting ■ semihardwood Position along the shoot terminal or subterminal Germination Viability ■ volves successive hot and cold phases, as happens in the wild. Optimal treatments are lengthy, lasting for periods of 24 to 28 weeks, and shorter periods of treat ment are suggested (2 weeks at 25 ºC + 2 weeks at 3 ºC + 2 weeks at 25 ºC + 12 to 16 weeks at 3 ºC), al though they may not be suitable for all seed lots. See ley and Damavandy (1985) estimate that cold stratification at 4 ºC for 100 days is the optimal treat ment for ending dormancy. Nursery practice ■ ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Number of internodes Size 12 Although it is hard to propagate the Saint Lucie cherry from cuttings, some selected genotypes are multiplied regularly for use as rootstocks for Prunus avium vari eties. The cuttings should be buried 10 cm deep in a perlite substrate or a mix of peat and perlite under a mist system (Bush, 1978; Vlasic, 1972) and hormones, which are indispensable for root formation, should be applied (Lipecki and Selwa, 1978). Ford et al. (2002) 4089 % Emergence ■ late spring, may be completed in the second spring Collecting time JulyAugust Auxin concentration 0.5 1 % recommend treating the parent plants with gibberellin to obtain rejuvenated material. In vitro propagation is the method used commercially for the production of Prunus mahaleb for use as a root stock. To initiate the culture, shoots obtained at the start of budding are used as explants (Dradi et al., 1996; Saponari et al., 1999). 111 Prunus mahaleb Pregermination treatments References General references Blanca G, Díaz de la Guardia C (1998) Prunus L. In: Muñoz Garmendia F, Navarro C (eds). Flora Ibérica. Vol 6. CSIC, Madrid Catalán G (1991) Semillas de árboles y arbustos forestales. Ministerio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Baskin CC, Baskin JM (1998) Seeds. Ecology, biogeography, and evolution of dormancy and germination. Academic Press, San Diego Bush R (1978) Summer rooting of stone fruit understock cut tings. Combined Proceedings of the International Plant Pro pagators Society 28:6364 Dradi G, Vito G, Standardi A (1996) In vitro mass propagation of eleven Prunus mahaleb ecotypes. Acta Horticulturae 410:477483 Ford YY, Taylor JM, Blake PS, Marks TR (2002) Gibberellin A3 stimulates adventitious rooting of cuttings from cherry (Pru nus avium). Plant Growth Regulation 37:127133 García C, Arroyo JM, Godoy JA, Jordano P (2005) Mating pat terns, pollen dispersal, and the ecological maternal nei ghbourhood in a Prunus mahaleb L. population. Molecular Ecology 14:1821–1830 García C, Jordano P, Godoy JA (2007) Contemporary pollen and seed dispersal in a Prunus mahaleb population: patterns in dis tance and direction. Molecular Ecology 16:19471955 Godoy JA, Jordano P (2001) Seed dispersal by animals: exact identification of source trees with endocarp DNA microsatel lites. Molecular Ecology 10:2275–2283 Jordano P (1993) Pollination biology of Prunus mahaleb L.: de ferred consequences of gender variation for fecundity and seed size. Biological Journal of the Linnean Society 50:6584 Jordano P, García C, Godoy JA, GarcíaCastaño, JL (2007) Dif ferential contibution of frugivores to complex seed dispersal patterns. Proceedings of the National Academy of Sciences of the USA 104:32783282 Jordano P, Godoy JA (2000) RAPD variation and population genetic structure in Prunus mahaleb (Rosaceae), an animal dispersed tree. Molecular Ecology 9:12931305 Lipecki J, Selwa J (1978) The effect of coumarin and some re lated compounds on the rooting of softwood cuttings of Pru nus mahaleb. Acta Horticulturae 80:7981 Saponari M, Bottalico G, Savino V (1999) In vitro propagation of Prunus mahaleb and its sanitation from prune dwarf virus. Advances in Horticultural Science 13:5660 Seeley SD, Damavandy H (1985) Response of seed of seven deciduous fruits to stratification temperatures and implica tions for modelling. Journal of The American Society for Hor ticultural Science 110:726729 Suszka B, Muller C, BonnetMasimbert M (1994) Graines des feuillus forestiers, de la récolte au semis. INRA, Paris Vlasic A (1972) Mahaleb propagation by cuttings. Jugoslo vensko Vocarstvo 6:693698 Prunus mahaleb 112 Prunus spinosa L. EN: blackthorn, sloe EL: τσαπουρνιά, προύμνη η ακανθώδης ES: endrino, espino negro FR: prunellier, épine noire IT: prugnolo, pruno selvatico PT: abrunheirobravo, ameixeira Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Northern Africa Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Diagnostic traits P. spinosa is a shrub, usually 1 to 3 m in height al though it can sometimes reach 6 m. It is a spiny de ciduous plant with blackish bark and many twisting branches. Its leaves are obovate, oblanceolate or al most elliptic, up to 4 cm long, glabrescent or pubes Reproductive biology Sex expression ■ hermaphroditism Flowering white flowers, solitary or in fascicles of two or three ■ from (January) February to May, before or at the same time as leaves ■ Pollination ■ ■ Montenegro, Albania, Greece, Turkey, Tunisia, Algeria, Morocco The blackthorn is found in thorny thickets, glades and forest fringes, on riversides and bordering paths. It grows on different types of soil but prefers alkaline to slightly acid substrates. cent above and more or less pubescent beneath. Flow ers are mostly solitary, sometimes arranged in clusters of two to three, with white petals that are occasionally veined with red. Pedicels are glabrous or puberule and are shorter than the ripe fruit. entomophilous selfincompatible Fruiting Ripening ■ ■ dark blue or blackish violet, subglobose or ovoid drupe, pruinose ■ 720 mm from September to December ■ dispersal by frugivorous vertebrates 113 Prunus spinosa Rosaceae Variation and Hybridisation Prunus spinosa is an allotetraploid species that may have derived from a cross between Prunus cerasifera and some other unknown species (ReyndersAloisi and Grellet 1994). It has a high degree of morphological and genetic variation (Mohanty et al., 2000). This vari ation could be due to the fact that P. spinosa does not seem to exhibit apomixis, and its reproductive system would therefore only be associated with pollinators (Guitian et al, 1993). The species also seems to be self incompatible and thus requires crosspollination in order to bear fruit (Yeboah Gyan and Woodell, 1987). It intercrosses with P. insititia, producing hybrids (P × fruticans Weihe) that are difficult to recognise. Studies using molecular techniques have shown that interpopulation variation is relatively low in the black thorn when compared to other woody species and that it does not exhibit any kind of spatial structuring pat tern, perhaps because of the rapid and easy dispersal of the species by animals. However, it would seem that southern populations – possible refuges during glacia tions – tend to have higher levels of diversity, and in clude specific genetic variants (Mohanty et al., 2002). This makes it advisable to be cautious when moving re productive materials between areas; using local mate rial is recommended. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from late summer to autumn ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 84160 g ■ purity: 100 % Fruit abortion during the initial stage of development seems to be frequent in the blackthorn, to a degree that varies from one plant to another (Guitián et al., 1992). ■ ■ prechilling (1224 weeks) preheating (24 weeks) + prechilling (4–18 weeks) Conditions ■ 18 ºC to 22 ºC Prunus spinosa 114 Blackthorn seeds, like those of other Prunus species, have dormant embryos, and thus require prolonged cold stratification. They may enter a second period of dormancy (secondary dormancy) if this cold stage is in terrupted by drying at room temperature (Baskin and Baskin, 1998) or by a rise in temperature. However, in duction of secondary dormancy by raising the temper ature is used in Prunus avium to achieve better germination percentages. Suszka et al. (1994) recom mend applying a stratification system that involves T: 5 ºC to 4 ºC MC: 48 % ■ airtight container ■ Collection of material should not concentrate only on the most productive individuals. Germination under controlled conditions Pregermination treatments 89250 g Germination Viability ■ 7090 % successive hot and cold phases, as happens in the wild. Optimal treatments are lengthy, lasting for periods of 24 to 28 weeks, and shorter periods of treatment are suggested (2 weeks at 25 ºC + 2 weeks at 3 ºC + 2 weeks at 25 ºC + 12 to 16 weeks at 3 ºC), although they may not be suitable for all seed lots. Seeley and Dama vandy (1985) estimate that cold stratification at 4 ºC for 100 days is the optimal treatment for ending dormancy. Sowing season ■ late winter or early spring, with treatment Vegetative propagation Type of cutting ■ hardwood Position along the shoot basal or middle Nursery practice ■ ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Number of internodes Size 10 15 cm The blackthorn is normally propagated from seed al though occasionally it is multiplied using hardwood cuttings taken from parent plants grown for that spe cific purpose. Results obtained using material from wild individuals display great variability (Ruiz, 1989). References General references Blanca G, Díaz de la Guardia C (1998) Prunus L. In: Muñoz Gar mendia F, Navarro C (eds). Flora Ibérica. Vol 6. CSIC, Madrid Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Webb DA (1968) Prunus L. In: Tutin TG et al. (eds). Flora Eu ropaea. Vol 2. Cambridge University Press, Cambridge Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Baskin CC, Baskin JM (1998) Seeds. Ecology, biogeography, and evolution of dormancy and germination. Academic Press, San Diego Battistini A, Paoli G (2002) Large scale micropropagation of several peach rootstocks. Acta Horticulturae 592:2933 Guitián J, Guitián P, Sánchez JM (1993) Reproductive biology of two Prunus species (Rosaceae) in the Northwest Iberian Peninsula. Plant Systematics and Evolution 185:153165 Guitián J, Sánchez JM, Guitián P (1992) Niveles de fructifi cación en Crataegus monogyna Jacq., Prunus mahaleb L. y Prunus spinosa L. (Rosaceae). Anales del Jardín Botánico de Madrid 50:239245 Emergence ■ late spring, may be completed in the second spring Collecting time winter Auxin concentration 0.5 1 % Trials of in vitro propagation of hybrids between this species and other Prunus, used as rootstock for plum and peach varieties, have been conducted (Battistini and Paoli, 2002; Krizan et al., 2007). Krizan B, Ondrusikova E, Trckova K, Benedikova D (2007) Ef fects of paclobutrazol and indole3butyric acid on in vitro rooting and growth of some rootstocks of the genus Prunus L. Europena Journal of Horticultural Science 72:198201 Mohanty A, Martín JP, Aguinagalde I (2000) Chloroplast DNA diversity within and among populations of the allotetraploid Prunus spinosa L. Theoretical and Applied Genetics 100:1304–1310 Mohanty A, Martín JP, Aguinagalde I (2002) Population genetic analysis of European Prunus spinosa (Rosaceae) using chloro plast DNA markers. American Journal of Botany 89:12231228 ReyndersAloisi S, Grellet F (1994) Characterisation of the ri bosomal DNA units in two related Prunus species (P. cerasifera and P. spinosa). Plant Cell Reports 13:641646 Ruiz J (1989) Cultivo del endrino (Prunus spinosa L.) en Nava rra. Navarra Agraria 44:58 (online URL http://www.grn.es/fl/public/a10.htm) Seeley SD, Damavandy H (1985) Response of seed of seven deciduous fruits to stratification temperatures and implica tions for modelling. Journal of The American Society for Hor ticultural Science 110:726729 Suszka B, Muller C, BonnetMasimbert M (1994) Graines des feuillus forestiers, de la recolte au semis. INRA, Paris Yeboah Gyan K, Woodell SRJ (1987) Flowering phenology, flower colour and mode of reproduction of Prunus spinosa L. (Blackthorn), Crataegus monogyna Jacq. (Hawthorn), Rosa canina L. (Dog Rose) and Rubus fruticosus L. (Bramble) in Ox fordshire, England. Functional Ecology 1:261268 115 Prunus spinosa Nursery production Rubus ulmifolius Schott Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Western Asia, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Diagnostic traits Rubus ulmifolius is a spiny, semideciduous bush. It is one of the few European species of the genus that re produces sexually, and is diploid. Its diagnostic traits include dark mauve, pruinose turions; alternate leaves, with five leaflets, white tomentose beneath (with stel late hairs); stipules linear, with the upper side of the Reproductive biology Sex expression ■ hermaphroditism Flowering ■ ■ pink, sometimes white flowers, clustered in cymes from May to August Rosaceae EN: elmleaf blackberry EL: βάτος ES: zarzamora FR: ronce (commune) IT: rovo PT: silva Pollination ■ Greece (incl. Kriti), Turkey, Tunisia, Algeria, Morocco The elmleaf blackberry grows in glades and forest fringes, humid thickets, hedges bordering roads and cultivated land, ravines and riverside areas. It is indif ferent to the mineral content of the substrate, and prefers warm temperate climates. petioles sulcate on the lower half only; smooth, pink or sometimes white petals. It produces abundant shiny black drupes. It is, however, a very polymorphic species, particularly as regards traits such as leaf shape, rami fication of inflorescences or petal colour. entomophilous Fruiting Ripening ■ ■ ■ shiny, black polydrupe about 10 mm from August to November ■ dispersal by frugivorous vertebrates Rubus ulmifolius 116 Variation and Hybridisation It is sometimes difficult to identify species of the Rubus genus. Many taxa have been included under Rubus ul mifolius because of its high level of polymorphism, the result of its phenotypic plasticity and facility for pro ducing lowstability hybrids. Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from late summer to autumn ■ gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 255 g ■ purity: 6098 % Large intra and interindividual differences exist in fruit characteristics of the species, which may exhibit large 23 g fruits with few seeds or small fruits with many seeds (Jordano, 1982). Germination under controlled conditions Pregermination treatments ■ ■ prechilling (1216 weeks) preheating (812 weeks) + prechilling (812 weeks) Conditions ■ ■ 30 / 15 ºC; 25 / 10 ºC light (12 h/day) The seeds of the elmleaf blackberry germinate with difficulty, due to their hard coat. Scarification followed by cold stratification has achieved good results in other Rubus species. Moore et al. (1994) and Peacock and Nursery production Sowing season ■ spring, with treatment ■ Germination Viability ■ 65 % Hummer (1996) used concentrated sulphuric acid. However, Campbell et al. (1988) obtained the best re sults by scarifying manually or treating the seeds with a 15% sodium hypochlorite solution for 18 hours. Nursery practice ■ T: 4 ºC MC: 48 % ■ airtight container ■ forestpot 300 cm3: 1/0 or 2/0 container 3.5 l: 1/1 Emergence ■ 1 to 3 months 117 Rubus ulmifolius Tolerance to desiccation: ORTHODOX Vegetative propagation Type of cutting ■ ■ root semihardwood Position along the shoot basal or middle Number of internodes Size 8 10 cm 12 The most common way of propagating most species of the genus Rubus is to use root cuttings. Semihardwood cuttings can be taken from parent plants or from shoots obtained from root cuttings. If mother plants are used, the cuttings should come from short shoots as they are more vigorous and form better roots than those obtained from very long shoots (Busby and Himelrick, 1999). Cut tings should be placed under mist in an aerated sub References General references HeslopHarrison Y (1968) Rubus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 2. Cambridge University Press, Cambridge Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin MonasterioHuelin E (1998) Rubus L. In: Muñoz Garmendia F, Navarro C (eds). Flora Ibérica. Vol 6. CSIC, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Broome OC, Zimmerman RH (1978) In vitro propagation of blackberry. HortScience 13:151153 Busby AL, Himelrick DG (1999) Propagation of blackberries (Rubus spp.) by stem cuttings using various IBA formulations. Proceedings of the Seventh International Rubus Ribes Sympo sium 505:327332 Campbell PT, Erasmus DJ, van Staden J (1988) Enhancing seed germination of sand blackberry. HortScience 23:560561 Collecting time spring JuneAugust Auxin concentration none 0.5 % strate. It is also possible, but not very common, to use hardwood cuttings (Zimmerman et al., 1980). A variety of trials of in vitro propagation of the genus Rubus have been carried out. Regeneration is per formed using meristems (Bromme and Zimmerman, 1978; Ferradini et al,. 1997) or leaf explants (Graham et al, 1997; Jun et al., 2006). Ferradini N, Effati M, Standardi A (1997) Propagazione in vitro di alcuni genotipi di Rubus. Italus Hortus 4:38 Graham J, Iasi L, Millam S (1997) Genotypespecific regene ration from a number of Rubus cultivars. Plant Cell Tissue and Organ Culture 48:167173 Jordano P (1982) Migrant birds are the main seed dispersers of blackberries in southern Spain. Oikos 38:183193 Jun WY, Ming X, Hua JG, Bo SC, Qin ZH, Le HP (2006) In vitro organogenesis and plant regeneration from leaves of blackberry (Rubus occidentalis). Journal of Fruit Science 23:468470 Moore JN, Brown GJ, Lundergan C (1974) Effect of duration of acid scarification on endocarp thickness and seedling emer gence of blackberries. HortScience 9:204205 Peacock DN, Hummer KE (1996) Pregermination studies with liquid nitrogen and sulphuric acid on several Rubus species. HortScience 31:238239 Zimmerman RH, Galletta GJ, Broome OC (1980) Propagation of thornless blackberries by onenode cuttings. Journal of the American Society for Horticultural Science 105:405407 Rubus ulmifolius 118 EN: willow, osier EL: ιτιά ES: sauce, mimbre FR: saule, osier IT: salice PT: salgueiro, borrazeira Salix spp. Salix alba L. Salicaeae The most common species of willow in the Mediter ranean region are found in riparian areas and wetlands, on many different types of soil. They can easily with stand waterlevel fluctuations and usually remain on river banks permanently, behaving like pioneers due to their facility for vegetative propagation and their abil ity to take root again after periodic floods. Among the species included in this guide, S. fragilis and S. triandra are present in the Mediterranean region but are more common in other, cooler areas of their distribution range. S. atrocinerea and S. eleagnos are also species that tend to grow in cooler environments than S. pur Diagnostic traits Willows are trees or shrubs with alternate, rarely op posed, deciduous leaves with short petioles and winter buds coated with a single scale. Willows exhibit a wide range of morphological variations at intraspecific level, especially as regards vegetative structures, and deter purea, S. salviifolia and S. pedicellata. Of these three, the latter two are the most thermophilous and are only found in the Mediterranean region. Willows grow on alkaline to neutral soils but some species have clear preferences. This is the case of the calcicole S. eleagnos, or of S. salviifolia, which thrives on acid substrates, while S. fragilis and S. purpurea prefer neutral soils; S. atrocinerea avoids salty ground, but S. alba can with stand a certain level of salinity. The distribution of the Salix species that occur in the Eu ropean Mediterranean Region is given in an Appendix. mination can thus be somewhat complex in young in dividuals or outside the flowering season. Traits that make it possible to distinguish the riparian species found in the Mediterranean Region can be found in an Appendix. 119 Salix Distribution and Ecology Reproductive biology Sex expression ■ dioecy Flowering flowers clustered in catkins ■ from January to March, from February to April, from March to May (from more to less thermophile) ■ Pollination ■ entomophilous and anemophilous Although willowflowers produce nectar, it has been shown that they may also be pollinated by the wind. The effectiveness of anemophile pollination seems to Variation and Hybridisation Within the Salix genus, dioecy, intraspecific morpho logical variation and the relatively frequent occurrence of natural hybridisation, which may even produce fer tile descendants, often make it difficult to determine taxonomical limits and assign individuals to a particu lar species. Thus, S. amplexicaulis is very close to S. pur purea, differing only in the morphological traits of its leaves. S. atrocinerea exhibits a high level of morpho logical variation and may hybridise with willows of cooler climates such as S. aurita or S. caprea or, in areas of contact, with its vicariant S. cinerea L., from which it differs in the reddish colouring of the hairs on its leaves. S. purpurea frequently hybridises with S. vimi nalis, while S. salviifolia might hybridise with S. pedi cellata in some areas of its distribution range. Another complex situation is that of S. × rubens, a species that comprises the hybrids of Salix alba and Salix fragilis; it seems to have two genetically differ entiated groups, each similar to one of the parent species, but this division may or may not match the at tributions based on morphological traits (Triest et al., 2000; De Cock et al., 2003). Notwithstanding the pos sibility of hybridisation, the genetic similarity to one or the other parent species would be the consequence of a low level of genomic affinity between these, which would in turn result in low recombination potential, thereby preventing introgression (Barcaccia et al., 2003). Another example of variation in willows is the recog nition of subspecies in Salix alba, S. triandra and S. purpurea. Fruiting Ripening ■ ■ ■ capsule 24 mm from March to June, one to two months after flowering ■ dispersal by wind vary a lot between species, possibly in relation to the morphological characteristics of female aments and flowers (Karrenberg et al, 2002). Some of the species have in the past been widely dis seminated by man, given their use in basketry, and may have become naturalised in many areas of Europe; this could be the case of some populations of Salix fragilis and S. triandra. There are many ornamental varieties and there are even hybrids resulting from artificial crossing of different species (Newsholme, 1992). Other taxa have also been introduced into the Mediterranean region, either for ornamental purposes (most com monly, S. babylonica) or for use in basketry (S. viminalis L., S. eriocephala Michx.). The use of these types of ma terial in revegetation and restoration projects is not recommended. Although willows reproduce easily by means of vege tative propagation, they are also scattered by the wind and, secondarily, by water during spring floods, so a certain degree of intrapopulational variation and gene flow between populations is to be expected. Thus, fruits or cuttings collected from populations that are close to each other need not be identified as different lots. However, it should be remembered that populations may be less variable in river basins with alterations in the natural flowregime, as these promote vegetative regeneration of populations at times of unseasonal floods (Basroum, 2002), or increase genetic isolation by reducing the level of gene flow between populations (Lascoux et al., 1996). Salix 120 Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ sequence for dehiscent fruits ■ purity: 6070 % Collecting must be carried out when the capsules ripen, taking on a yellowishbrown colour, and the hair tufts of the seeds begin to emerge. This requires close con trol in the field, as seeds are soon scattered by the wind. Once the fruits have been harvested, they are left to dry at room temperature for one or two days until they open. Although it is not strictly necessary, the tufts of hairs can be removed by straining the seeds through a fine mesh with the aid of compressed air. 0.060.08 g (S. alba), 0.14 g (S. fragilis) Cleaning and preparation should be carried out in less than a week, since the seeds soon lose their viability if kept in normal temperature and moisture conditions. If they are not to be used immediately, the seeds can be kept in airtight containers at 4 ºC for a month; storage for longer periods (3 to 5 years) will require moisture control and storage in airtight containers at below 0 ºC (Maroder et al., 2000). Germination under controlled conditions Pregermination treatments ■ without treatment Nursery production Sowing season ■ spring, without treatment, immediately after collecting Conditions ■ 20 ºC to 25 ºC Nursery practice bareroot: circumference up to 68 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ The seeds should not be covered or pressed into the substrate after sowing. Seedlings are very delicate and are susceptible to drought during the first month. When plants are produced in containers, it is possible T: 18 ºC MC: 68 % ■ airtight container ■ Germination Viability ■ 9095 % Emergence ■ 1224 h after sowing to sow in small pots (volume up to 7075 cm3). Once the seedlings have become established in these smaller cells, they can be removed and transplanted into the growth containers. 121 Salix from March to June, variable by species and by site ■ gathering by hand or using longhandled tools Vegetative propagation Type of cutting ■ hardwood Position along the shoot indifferent Number of internodes Size 30 50 cm Vegetative propagation of willows growing in riparian areas is generally easy. Chmelar (1974) establishes two groups of willows according to the manner of rooting: the most common group that roots extensively along virtually the entire stem, as in S. alba, S. purpurea or S. eleagnos, and the group in which roots are formed only at the base, as in S. atrocinerea (Vieitez and Peña, 1968). In willows it is possible to use material of over a year in age with a diameter larger than 20 mm. Har vested material may be stored at 4 ºC for two months without problems (Chmelar, 1974; Volk et al., 2004). In References General references Blanco P (1993) Salix L. In: Castroviejo S et al. (eds). Flora ibérica. Vol. 3. CSIC, Madrid Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Christensen K.E (1997) Salix L. In: Strid A, Tan K (eds). Flora Hellenica. Vol 1. Koeltz Scientific Books, Königstein Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Rechinger KH, Akeroyd JR (1964) Salix L. In: Tutin TG et al. (eds). Flora Europaea. Vol 1. 2nd edn. Cambridge University Press, Cambridge Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Barcaccia G, Meneghetti S, Albertini E, Triest L, Lucchin M (2003) Linkage mapping in tetraploid willows: segregation of molecular markers and estimation of linkage phases support Collecting time December to March Auxin concentration none species which root easily, it is possible to use minicut tings (813 mm thick and 8 cm long) and root them di rectly in forest pots (Dumroese et al., 2003; Mathers, 2003). It is also feasible to use softwood cuttings in the summer under conditions of high relative humidity (Newsholme, 1992). There are many studies of micropropagation of the genus Salix. Regeneration is possible from meristems (Chung and Carrasco, 2001) and from axillary buds (Bergmann et al., 1985). an allotetraploid structure for Salix alba x Salis fragilis inter specific hybrids. Heredity 90:169180. Basroum N (2002) Relative contribution of sexual and asex ual regeneration strategies in Populus nigra and Salix alba during the first years of establishment on a braided gravel bed river. Evolutionary Ecology 15:255279 Bergman L, Von Arnold S, Eriksson T (1985) Effects of N6 benzyladenine on shoots of five willow clones (Salix spp.) cul tured in vitro. Plant Cell Tissue and Organ Culture 4:135144 Chmelar J (1974) Propagation of willows by cuttings. New Ze aland Journal of Forestry Science 4:185190 Chung P, Carrasco B (2001) Micropropagation of Salix spp. for foliate meristems. Report of the 21st session of the Interna tional Poplar Commission and 40th session of its Executive Committee, 2428 September 2000, Portland De Cock K, Lybeer B, Vander Mijnsbrugge K, Zwaenepoel A, Van Peteghem P, Quataert P, Breyne P, Goetghebeur P, Van Slycken J (2003) Diversity of the willow complex Salix alba S. x rubens S. fragilis. Silvae Genetica 52:148153 Dumroese RK, Wenny DL, Morrison SJ (2003) Propagation pro tocol for container willows and poplars using minicuttings. Native Plants Journal 4:137139 Karrenberg S, Kollmann J, Edwards PJ (2002) Pollen vectors and inflorescence morphology in four species of Salix. Plant Systematics and Evolution 235:181188 Lascoux M, Thorsén J, Gullberg U (1996) Population structure of a riparian willow species, Salix viminalis L. Genetical Re search, Cambridge 68:4554 Salix 122 Mathers T (2003) Propagation protocol for bareroot willows in Ontario using hardwood cuttings. Native Plants Journal 5:134136 Newsholme C (1992) Willows. The genus Salix. Timber Press, Portland Triest L, De Greef B, De Bondt R, Van Slycken J (2000) RAPD of controlled crosses and clones from the field suggests that hy brids are rare in the Salix albaSalix fragilis complex. Hered ity 84:555563 Vieitez E, Peña J (1968) Seasonal Rhythm of Rooting of Salix atrocinerea cuttings. Physiologia Plantarum 21:544555 Volk TA, Ballard B, Robison DJ, Abrahamson LP (2004) Effect of cutting storage conditions during planting operations on the survival and biomass production of four willow (Salix L.) clones. New Forests: International Journal on the biology, bio technology and management of afforestation and reforesta tion 28:6378 123 Salix Maroder HL, Prego IA, Facciuto GR, Maldonado SB (2000) Sto rage behaviour of Salix alba and Salix matsudana seeds. An nals of Botany 86:10171021 Sambucus nigra L. Distribution and Ecology General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Tunisia, Algeria, Morocco Sambucus nigra is found as scattered trees on the edge of humid forests, among spiny deciduous bushes and, Diagnostic traits The black elder is a deciduous shrub or small tree that can reach a height of 10 m. The pith in stems and branches is large, white and spongy. Its leaves are op posite, composed of 3 to 9 elliptic, ovate or ovate lanceolate leaflets, usually asymmetric at the base, Reproductive biology Sex expression ■ hermaphroditism Flowering small white or creamy flowers, clustered in corymbs ■ from April to July ■ Caprifoliaceae EN: common elder EL: κουφοξυλιά ES: saúco FR: sureau noir IT: sambuco PT: sabugueiro Pollination ■ in Mediterranean environments, in valleys and thal wegs outside riparian areas or associated with perma nent watercourses. It is indifferent to the mineral nature of the substrate but requires loose, humid soils. It grows well on eutrophic and disturbed areas and re sprouts from the stump. The natural distribution range of the species is difficult to establish accurately, since the black elder has been widely cultivated for its fruit. with serrate margins. It is easily distinguished from Sambucus racemosa in that the latter has red fruits, its racemose inflorescences have smaller, greenish coloured flowers and it requires cooler, more humid climates. entomophilous Fruiting Ripening ■ ■ ■ black, globose drupe 68 mm Sambucus nigra 124 from August to September ■ dispersal by frugivorous vertebrates Variation and Hybridisation There is no information on intraspecific variation and hybridisation for this taxon. Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from August to October gathering by hand or using longhandled tools sequence for fleshy fruits ■ seed weight / kg fruit: 35110 g ■ purity: 9899 % Common elder usually bears abundant fruit every year; however, fruit production can be low in very adverse climates or in individuals that grow in the shade. The 23 g proportion of fruits with viable seeds varies between individuals, as parthenocarpy and embryo abortion can both occur (Bolli, 1994; Atkinson and Atkinson, 2002). Germination under controlled conditions Pregermination treatments preheating (612 weeks) + prechilling (12 weeks) ■ prechilling (12 weeks) + freezing (1 day) ■ Conditions ■ ■ 30 / 15 ºC; 20 / 10 ºC light (14 h/day) Common elder seeds experience morphophysiological dormancy; at the time of fruit ripening, the embryo is not fully developed. It requires a period of hot stratifi cation to elongate, followed by a period of cold Nursery production Sowing season ■ early autumn, without treatment, or spring, with treatment Germination Viability ■ 4585 % stratification to elicit germination. The hot stratifica tion phase may be replaced by the use of gibberellic acid solution at a concentration of 1,000 mg/l (Hiday ati et al., 2000). Nursery practice forestpot 300 cm3: 1/0 ■ container 3.5 l: 1/1 ■ T: 4 ºC MC: 48 % ■ airtight container ■ Emergence ■ the first spring, may be completed in the second spring 125 Sambucus nigra Tolerance to desiccation: ORTHODOX Vegetative propagation Type of cutting ■ ■ semihardwood hardwood, heeled Position along the shoot indifferent basal Number of internodes Size 10 cm 15 cm The common elder propagates very easily from cuttings, even when adult individuals are used (Good and Bellis, 1978; Legind and Kaak, 2002). Semihardwood cuttings can be obtained from almost the whole plant, but should be taken before they become very lignified and the spongy pith begins to form (Sandrap, 2000). The leaves on the upper internode should be left on, as this improves the quality of the plant obtained (Ventrella et al., 1998). It is recommended that cuttings be kept References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Ferguson IK (1976) Sambucus L. In: Tutin TG et al. (eds). Flora Europaea. Vol 4. Cambridge University Press, Cambridge Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Ruiz Téllez T, Devesa JA (2007) Sambucus L. In: Castroviejo S (coord). Flora Ibérica. Vol 15. CSIC, Madrid Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Atkinson MD, Atkinson E (2002) Sambucus nigra L. Journal of Ecology 90:895923 Bolli R (1994) Revision of the genus Sambucus. Dissertationes Botanicae 223:1227 Brassard N, Richer C, Charlebois D (2004) Micropropagation of elderberry (Sambucus nigra ssp. canadensis). Agriculture and AgriFood Canada/ Horticulture Research and Development Collecting time AprilSeptember winter Auxin concentration none none under mist (Gupta, 1994). In the event of using hard wood material, the cuttings should be cut with a heel so that the spongy pith is not exposed at the base (Legind and Kaak, 2002). In vitro regeneration of the common elder is possible and is carried out using internodal segments (Brassard et al., 2004). Centre. (online URL http://www.cshs.ca/brassard/200407Mi cropropagationelderberryv3files/slide0001.htm) Good JE, Bellis JA, Munro RC (1978) Clonal variation in roo ting of softwood cuttings of woody perennials occurring na turally on derelict land. International Plant Propagators Society Combined proceedings 28:192201 Gupta VN (1994) Effect of growth regulators on rooting in Sambucus nigra L. semihardwood cuttings under intermit tent mist. Horticultural Journal 7:145149 Hidayati SN, Baskin JM, Baskin CC (2000) Morphophysiologi cal dormancy in seeds of two North American and one Eurasian species of Sambucus (Caprifoliaceae) with underde veloped spatulate embryos. American Journal of Botany 87: 1669–1678 Legind E, Kaack K (2002) Propagation of elder. Gron Viden, Havebrug 143 Sandrap A (2000) La culture des sureaux (Elder). Fruit Belge 68:130132 Ventrella MC, Alves LOLR, Garcia VB, Amaral JP, Buim ARG (1998) Efeito das folhas e do tipo de estaca no desenvolvi mento do sistema radicular em estacas de sabugueiro (Sam bucus nigra L.). UNIMAR Ciencias 7:8185 Sambucus nigra 126 EN: saltcedar, tamarisk EL: αρμυρίκι ES: taray FR: tamaris IT: tamerice PT: tamargueira Tamarix spp. Tamarix gallica L. Tamaricaceae Tamarisks are species that grow in arid and semiarid climates but require temporary edaphic humidity from surface or ground water. They are found in riverine areas with water regimes ranging from permanent wa tercourses to ephemeral streams, in humid depressions and in sandy shoreline areas, as scattered individuals or in continuous formations depending on water avail ability. Tamarix boveana, T. canariensis and T. dalmat ica withstand salinity very well and may be found next to swamps and saltmarshes in inland and coastal Diagnostic traits Tamarisks are freelybranching shrubs with small leaves that look like scales and glands that secrete salt. The taxonomy of the genus is quite complex, since its members exhibit very few external traits that are dis tinctive and easy to see. Diagnostic traits are usually related to the morphology of the small flowers, espe cially the androecium and the bracts that subtend the flowers (see the table of diagnostic traits in the Ap pendix), so it is difficult to classify individuals as be longing to a certain species unless they are flowering. Tamarix inflorescences can form on currentyear branches (aestival inflorescences) or on the previous year’s (vernal inflorescences). However, this trait can not be used for diagnosis since it is heavily influenced by local and annual weather conditions. Flowers may be tetramerous or pentamerous, but the number of flo ral parts is of no use as a diagnostic characteristic on its own, as it may be inconsistent. areas. T. canariensis, T. africana, T. tetranda and T. smyr nensis can withstand the cold relatively well and occur in more continental environments. The distribution of the Tamarix species that occur in the European Mediterranean Region is given in an ap pendix. Maps of the Eastern Mediterranean tamarisks should be taken as only approximate because of the lack of precise information about their distribution. The difficulty of assigning individuals to certain species on the basis of morphological traits, as in the case of Tamarix gallica and T. canariensis, is corroborated by molecular techniques. Thus Gaskin and Schaal (2003) were unable to distinguish between these two species by means of these techniques, perhaps because the species turned out to be the same taxon or because they were intercrossing. T. gallica and T. canariensis are also difficult to distinguish morphologically from T. africana in its summer forms (Baum, 1978). Some Asiatic species of the genus are cultivated for or namental purposes. These include T. ramosissima, which can be confused with T. smyrnensis (Baum, 1978). They should not be employed in restoration projects, since they may hybridise with native species. Indeed, evi dence has been found of hybridisation between T. ramosissima and T. canariensis or T. gallica (Gaskin and Schaal, 2003). 127 Tamarix Distribution and Ecology Reproductive biology Sex expression ■ hermaphroditism Flowering Pollination white or pink flowers, clustered in racemes ■ from March to June, some species sometimes also in autumn ■ ■ entomophilous Fruiting Ripening ■ ■ ■ capsule from 2 to 8 mm from May to August, some species sometimes also in autumn ■ dispersal by wind Variation and Hybridisation There is no information on intraspecific variation and hybridisation for natural populations of the Tamarix species in question. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ from May to August, sometimes in autumn ■ gathering by hand sequence for dehiscent fruits Sexual propagation of tamarisks is not commonly used in plant production, since vegetative propagation of the species is easily achieved. Collection should begin when capsules ripen; the catkins are briefly left to dry, to allow for full opening of the fruits. The small seeds are ■ without treatment Conditions ■ ■ ■ T: 18 ºC airtight container difficult to handle and it is therefore not necessary to separate them from their open capsules. These seeds rapidly lose their viability at room temperature, but may be preserved for 1 to 2 years if kept at tempera tures below 0 ºC. Germination under controlled conditions Pregermination treatments 0.031 g (T. gallica) 20 ºC to 25 ºC light Germination Viability ■ 8090 % Tamarix 128 Nursery production Sowing season ■ spring, without treatment, immediately after collecting Nursery practice bareroot: circumference up to 46 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ Early seedling growth is very slow. The substrate must be kept continually moist during seedling development. Once the seedlings become established they can with stand severe drought. When plants are produced in Vegetative propagation Type of cutting ■ hardwood Position along the shoot indifferent ■ 24 h after sowing containers, it is possible to sow in small pots (volume up to 7075 cm3). Once the seedlings have become es tablished in these smaller cells, they can be removed and transplanted into the growth containers. Number of internodes Size 20 30 cm Emergence Collecting time winter Auxin concentration none Planting minicuttings (8–13 mm diameter, 8 cm long) directly in forestpot is also possible. General references Baum BR (1968) Tamarix L. In: Tutin, TG et al. (eds). Flora Eu ropaea. Vol 2. Cambridge University Press, Cambridge Cirujano S (1993) Tamarix L. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Specific references Baum BR (1978) The genus Tamarix. The Israel Academy of Sciences and Humanities. Central Press, Jerusalem Gaskin JF, Schaal BA (2003) Molecular phylogenetic investi gation of U.S. Invasive Tamarix. Systematic Botany 28:8695 129 Tamarix References Ulmus minor Mill. Distribution and Ecology Distribución general: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Turkey, Cyprus, Libya, Tunisia, Algeria, Morocco Diagnostic traits Ulmus minor is a deciduous tree that can reach a great height (25 to 30 m). Its leaves range from ovallance olate to suborbicular, acute at apex, very asymmetrical at base, with the basal lobe shorter than the petiole and the margin irregularly dentate. The seeds are con Reproductive biology Sex expression ■ androdioecy Flowering inconspicuous flowers, clustered in glomerules ■ from February to April, before leaf development ■ Ulmaceae EN: common elm, field elm EL: φτελιά, καραγάτσι ES: olmo común, álamo negro FR: orme champêtre, ormeau IT: olmo campestre, olmo comune PT: negrilho, ulmeiro The elm is a typical species of the Mediterranean ri parian forest, where it grows in stands or as more or less scattered individuals in areas where the phreatic water levels are deepest or the water supply is lowest in the summer, in contact with the zonal vegetation. It prefers cool, deep, baserich soils. Cultivated elms are commonly seen next to roads and ditches, or near rural buildings. tained in the upper third of the samara. It should not be confused with the Asiatic Ulmus pumila, which is in widespread gardening use because of its resistance to Dutch elm disease. The latter’s leaves are barely asym metrical and their margins have simple teeth. Pollination Fruiting Ripening ■ ■ ■ ■ anemophilous selfincompatible Ulmus minor reproduces naturally through seeds and by resprouting from the root; genotypes with sterile fe male flowers tend to produce a large number of empty ■ samara up to 20 x 17 mm from March to April ■ dispersal by wind fruits due to lack of pollination and to seed abortion (LópezAlmansa and Gil, 2003). Ulmus minor 130 Ulmus minor Miller (emend. Richens sensu latissimo) is a complex with great morphological variation (Richens, 1983) in which some authors have distinguished sev eral taxa (Melville, 1975). Among these, U. minor var. vulgaris (Aiton) Richens, accepted by some authors as Ulmus procera Salisb., can be distinguished from Ulmus minor var. minor in that its leaves are rough on their upper side, with wide teeth and a short, hairy petiole, while the type variety has smooth, lustrous leaves with a long, glabrescent petiole. Another similar taxon is Ulmus canescens Melville (=Ulmus minor subsp. canescens (Melville) Bowicz & Ziel.), which is found in the central and eastern Mediterranean region. Its young twigs and the reverse of its leaves are densely pubescent. There are numerous intermediate forms among varieties, as well as hybrids with Ulmus glabra (U. x holandica Mill.) or Ulmus pumila, often including strong introgression and backcrosses, making identifi cation difficult. The species has been widely disseminated in the past and it is often difficult to determine whether a given population is indigenous or has become naturalised. Some authors doubt that the tree is native in certain northern areas of its current range of distribution (Richens and Jeffers, 1985). On the other hand, studies performed using molecular techniques seem to confirm the massive propagation in Spain and Great Britain of a sterile clone of the vulgaris variety which grows very fast but is particularly susceptible to Dutch elm dis ease. This expansion could be due to the Romans’ use of trees of this clone for vinetraining (Gil et al., 2004). There is also evidence that both Ulmus plotii Druce (= U. minor Mill. var. lockii (Druce) Richens) and Ulmus an gustifolia (Weston) Weston (= U. minor Mill. subsp. an gustifolia (Weston) Stace) are varieties that have been disseminated in Great Britain because of the unique ness of some of their morphological traits and their ease of vegetative propagation (Coleman et al., 2000; Hollingsworth and Armstrong, unpublished data – cited in Coleman et al., 2000). In spite of its intensive use by humans, a geographic pattern of genetic variation has been assessed in the common elm, according to the results of molecular studies. This is possibly due to events in natural history, having to do with different refuges during glaciations, migration pathways and genetic isolation (Collin et al., 2002). The existence of geographic differences of ori gin is also reflected in the dissimilar behaviour of clones from disparate regions as regards traits of adap tive significance such as phenology (Ghelardini et al., 2006). Analyses using molecular techniques have also been performed in apparently natural Spanish popula tions, not made up of specimens of the abovemen tioned nonautochthonous clone of the vulgaris variety. These studies reveal a certain genetic variation and thus the existence of sexual propagation mechanisms in the dynamics of such populations (FuentesUtrilla, pers. com.). Dutch elm disease, a malady transmitted by several scolytids, has wiped out whole populations and nu merous individuals throughout the range of distribu tion of the species, leading to the disappearance of most adult elms. Populations have remained in the form of young plants that resprout from the roots of the tree but die once they have reached a certain size. To this should be added the ageold destruction of elms in fertile waterside habitats cleared for farming. The preservation of the species is thus considered a prior ity in several European countries. Several hybrids of Ulmus minor with Asiatic and Amer ican species that are resistant to the disease exist on the market, as well as some genotypes of the species that have shown their resistance in several selection programmes. Genetic transformation has been achieved in genotypes of the vulgaris variety and their resistance to Dutch elm disease is being evaluated (Gartland et al., 2005). The use of elms in restoration and reforestation proj ects can be controversial and some precautions must be taken. The first is to make sure that the material of choice is free from disease; the second, to ensure that new plantations do not jeopardise the survival and characteristics of natural populations that may be lo cated in neighbouring areas. In accordance with cur rent knowledge, with a view to complying with a series of basic principles that are essential for the preserva tion of the species, it is advisable to bear in mind the following recommendations: whenever possible, only use materials from riparian populations or individuals that exhibit signs of being indigenous and show no symptoms of Dutch elm dis ease. Even so, the use of materials that have not been tested can never guarantee resistance; avoid using the susceptible clone of the vulgaris vari ety that has been massively disseminated in the past in some countries, especially in grapegrowing areas. Other varieties should be used instead. If genetic 131 Ulmus minor Variation and Hybridisation identification is not possible, seed production may be used as a distinguishing trait to discriminate the un desirable, diseaseprone genotype, which is sterile; vegetative rather than seed propagation must be used when specimens of U. pumila or its hybrids are pres ent near the collection area, since U. minor can suf fer introgression by the Asiatic species; when there is no other option but to harvest from pop ulations that include individuals with symptoms of Dutch elm disease, only collect the seeds, as the veg etative material might be infected; genetic variation among lots should be encouraged by collecting materials from few individuals per popu lation in as many different populations as possible, especially when phenotypic homogeneity gives rea son to suspect that individuals belong to the same genotype; given the occurrence of varieties whose distribution is limited to certain areas and the estimated existence of a certain geographical pattern in the genetic vari ation of this species, it is advisable not to transfer materials over long distances; the use of genetically modified materials should be considered, with due regard to sterility or invasive behaviour patterns; finally, if healthy populations are found near the restoration area, the risk of introducing new individ uals which could act as a ‘bridge’ between diseased and healthy specimens must be carefully assessed. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ from April to May using longhandled tools or beating branches sequence for fruits that can be sown ■ purity: 8598 % Elm seeds quickly lose their viability at room tempera ture and ambient moisture conditions. In small lots, full Germination under controlled conditions Pregermination treatments ■ without treatment Conditions ■ 20 ºC Samara wings can be removed manually for germina tion in controlled conditions. 68 g (samara) T: 13 ºC to 0 ºC MC: 27 % ■ airtight container ■ seeds can be separated from empty seeds by means of visual inspection. Germination Viability ■ 1050 % Ulmus minor 132 Nursery production Sowing season ■ spring, without treatment, immediately after collecting Nursery practice bareroot: 40 g/m2; circumference up to 68 cm or total height up to 100150 cm 3 ■ forestpot 300 cm : 1/0 ■ container 3.5 l: 1/1 ■ When plants are produced in containers, it is possible to sow in small pots (volume up to 7075 cm3). Once the seedlings have become established in these smaller Vegetative propagation Type of cutting ■ ■ root semihardwood Position along the shoot basal or middle The common elm is propagated very easily using root segments and fairly easily when semihardwood cut tings are used (Kobert, 1979). The root cuttings should not be more than 15 mm in diameter. The semihard wood cuttings should be put to root in an environment with high relative humidity as elm leaves are particu larly sensitive to drying (Mittempergher et al., 1992). Hardwood material gathered in winter and put to root with bed heating does form roots, but has very low sur vival rates at the hardening off stage (Bartolini et al., 1997; Griffin and Schroeder, 2004). References General references ■ 1 to 2 weeks after sowing cells, they can be removed and transplanted into the growth containers. Number of internodes Size 5 8 cm 10 15 cm Emergence Collecting time early spring JuneJuly Auxin concentration none 0.5 % Owing to damage in natural populations caused by Dutch elm disease, in vitro propagation is a promising method for regenerating and conserving indigenous specimens. In recent years, a variety of regeneration trials have been conducted using cotyledons (Corre doira et al., 2002), leaves (Conde et al., 2004; Dorion et al., 2004) and segments of internodes (Diez and Gil, 2004; Dorion et al., 1993). Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Nicolás JL, Iglesias S, Alía R (2001) Fichas descriptivas de es pecies. In: García del Barrio JM et al. (coord). Regiones de identificación y utilización de material forestal de reproduc ción. Ministerio de Medio Ambiente, Madrid Christensen KI (1997) Ulmus L. In: Strid A, Tan K (eds). Flora Hellenica. Vol 1. Koeltz Scientific Books, Königstein Piotto B, Di Noi A (eds) (2001) Propagazione per seme di alberi e arbusti della flora mediterranea. ANPA, Roma Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Tutin TG (1993) Ulmus L. In: Tutin TG et al. (eds). Flora Euro paea. Vol 1. 2nd edn. Cambridge University Press, Cambridge 133 Ulmus minor Navarro C, Castroviejo S (1993) Ulmus. In: Castroviejo S et al. (eds). Flora Ibérica. Vol 3. CSIC, Madrid Specific references Bartolini G, Fagnani A, Mittempergher L, Panicucci M (1997) Propagazione del l’olmo (Ulmus spp.) per talea legnosa. Monti e Boschi 48:4851 Coleman M, Hollingsworth ML, Hollingsworth PM (2000) Application of RAPDs to the critical taxonomy of the English endemic Ulmus plotii Druce. Botanical Journal of the Linnean Society 133:241–262 Collin E, Santini A, Hollingsworth P (compilators) (2002) Final report RES GEN CT9678 (online URL http://www.cemagref.fr/Informations/Actualites/elm/final rap.htm) Gartland KMA, McHugh AT, Crow RM, Garg A, Gartland JS (2005) Biotechnological Progress in dealing with Dutch Elm Disease. In Vitro Cellular Development Biology Plant 41:364–367 Ghelardini L, Falusi M, Santini A (2006) Variation in timing of budburst of Ulmus minor clones from different geographical origins. Canadian Journal of Forest Research 36:19821991 Gil L, FuentesUtrilla P, Soto A, Cervera MT, Collada C (2004) English elm is a 2,000yearold Roman clone. Nature 431:1053 Griffin JJ, Schroeder KR (2004) Propagation of Ulmus parvifo lia `Emerald Prairie’ by Stem Cuttings. Journal of Environ mental Horticulture 22:5557 Conde P, Loureiro J, Santos C (2004) Somatic embryogenesis and plant regeneration from leaves of Ulmus minor Mill. Plant Cell Reports 22:632639 Kobert H (1979) Vegetative Vermehrung von Waldbaumen durch Triebstecklinge. Berichte der Eidgenossische Anstalt fur das Forstliche Versuchswesen 201:8 Corredoira E, Vieitez AM, Ballester A (2002) Somatic embryo genesis in elm. Annals of Botany 89:637644 LópezAlmansa JC, Gil L (2003) Empty samara and partheno carpy in Ulmus minor s.l. in Spain. Silvae Genetica 52:241243 Diez J, Gil L (2004) Micropropagation of Ulmus minor and U. minor x U. pumila from 4yearold ramets. Investigacion Agra ria, Sistemas y Recursos Forestales 13:249254 Dorion N, BenJouira H, Jouanin L (2004) Optimization of elm regeneration in vitro using leaf explants and evaluation of the process in the transformation experiments. Investigacion Agraria, Sistemas y Recursos Forestales 13:237247 Dorion N, Godin B, Bigot C (1993) Physiological state and clo nal variability effects on low temperature storage of in vitro shoot cultures of elms (Ulmus spp.). Scientia Horticulturae 56:5159 Melville R (1975) Ulmus. In: Stace CA (ed). Hybridisation and the flora of the British Isles. Academic Press, London Mittempergher L, Bartolini G, Ferrini F, Panicucci M (1992) As pects of elm propagation by soft and hardwood cuttings. Suelo y Planta 2:129137 Richens RH (1983) Elms. Cambridge University Press, Cambridge Richens RH, Jeffers JNR (1985) (publ. 1986) Numerical taxonomy and ethnobotany of the elms of northern Spain. Anales del Jardín Botánico de Madrid 42:325341 Ulmus minor 134 EN: laurustinus EL: άγρια δάφνη ES: durillo FR: lauriertin, viornetin IT: lentaggine PT: folhado Distribution and Ecology General distribution: Southwestern and Southeastern Europe, Western Asia, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, Albania, Greece, Turkey, Lebanon, Israel, Libya, Tunisia, Algeria, Morocco This thermophile shrub is typical of holmoak and Mediterranean pine forests, but may also grow in Diagnostic traits Viburnum tinus is an evergreen shrub that does not ex ceed 3 to 4 m in height. Its leaf traits make it easy to distinguish from other species found in Europe and in cluded in different sections of the genus. The leaves of V. tinus are entire, shiny green and persistent, while those of V. lantana and V. opulus, both of which are deciduous, have dentate margins and are very hairy in the former and palmatelobed in the latter. Moreover, Viburnum tinus L. maquis on cool and rather moist soils and in more humid Mediterranean forests. It is indifferent to bedrock type, although it prefers loose, rich soils. Laurustinus is not specifically a waterside species but it is worth considering for this use because of its need for some humidity as well as its interaction with ani mals. It could be planted in areas of transition between riparian and zonal vegetation. V. opulus produces fruits that are bright red instead of black when mature. The differences between V. tinus, V. lantana and V. op ulus have been also determined in phylogenetic stud ies using molecular markers (Donoghue et al., 2004; Winkworth and Donoghue, 2005). V. tinus is the most thermophile of the three species. 135 Viburnum tinus Caprifoliaceae Reproductive biology Sex expression ■ hermaphroditism Flowering ■ ■ Pollination white flowers clustered in cymes anthesis from November to June, immature inflores cences throughout the year ■ ■ entomophilous selfcompatible Variation and Hybridisation Three subspecies have been described: V. tinus subsp. rigidum (Vent.) P. Silva and Viburnum tinus subsp. sub cordatum (Trel.) P. Silva, which are found in the Canary Fruiting Ripening ■ ■ dark blue or black, ovoid drupe ■ 58 mm length from August to September, may remain on the shrub until winter ■ dispersal by frugivorous vertebrates Islands and the Azores, respectively, and Viburnum tinus L. subsp. tinus L., which occurs in the rest of the distribution range. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ autumn gathering by hand sequence for fleshy fruits ■ seed weight / kg fruit: 355650 ■ purity: 9598 % V. tinus exhibits annual fruitproduction fluctuations and bears a more abundant crop every three years (Herrera, 1998). Germination under controlled conditions Pregermination treatments ■ preheating (812 weeks) + prechilling (8–12 weeks) Conditions ■ ■ 30 / 20 ºC light Seeds of Viburnum tinus are very difficult to germinate. They have a combination of weak morphophysiologi cal dormancy and slow germination and require cyclic temperatures, as in the wild (Karlsson et al., 2005). In conventional hot and coldstratification treatment procedures, prechilling can be replaced by the applica 3980 g T: 0 ºC to 4 ºC MC: 48 % ■ airtight container ■ Removal of pulp is necessary for germination of Vibur num tinus seeds. Germination Viability ■ 4060 % tion of alternating temperatures in an incubator, with a lowtemperature peak of less than 15 ºC (García Fayos, 2001). A daily temperature regime of 20 ºC / 10 ºC (light/dark) in an incubator for 5060 weeks could be suitable for dormancy reduction and germination in seeds without pretreatment (Karlsson et al., 2005). Viburnum tinus 136 Sowing season ■ early autumn, without treatment, or spring, with treatment Vegetative propagation Type of cutting ■ semihardwood Position along the shoot terminal Nursery practice ■ ■ forestpot 300 cm3: 1/0 container 3.5 l: 1/1 Number of internodes Size 34 Cuttings of laurustinus can be collected almost all the year round, except when the plant is flowering (Cervelli, 2005; Lamb and Kelly, 1988). Application of a rejuve nation treatment to the parent plants speeds up and homogenises the rooting of cuttings (Pignatti and Crobeddu, 2005). The rooting process works better under mist; depending on weather conditions, bed heating may be recommended (Giroux et al., 1999). References General references Catalán G (1991) Semillas de árboles y arbustos forestales. Mi nisterio de Agricultura Pesca y Alimentación. ICONA, Madrid Ferguson IK (1976) Viburnum L. In: Tutin TG et al. (eds). Flora Europaea. Vol 4. Cambridge University Press, Cambridge Ruiz Téllez T, Devesa JA (2007) Viburnum L. In: Castroviejo S (coord). Flora Ibérica. Vol 15. CSIC, Madrid Specific references Cervelli C (2005) La specie arbustive della macchia mediterranea. Un patrimonio da valorizzare. Collana Sicilia Foreste 26:39154 Donoghue MJ, Baldwin BG, Winkworth RC (2004) Viburnum phylogeny based on chloroplast trnK intron and nuclear ribo somal ITS DNA sequences. Sysematic Botany 29:188198 GarcíaFayos P (coord) (2001) Bases ecológicas para la reco lección, almacenamiento y germinación de semillas de espe cies de uso forestal en la Comunidad Valenciana. Banc de Llavors Forestals, Generalitat Valenciana, Valencia Giroux GJ, Maynard BK, Johnson WA (1999) Comparison of perlite and peat:perlite rooting media for rooting softwood stem cuttings in a subirrigation system with minimal mist. Journal of Environmental Horticulture 17:147151 Emergence ■ the first spring, slow and irregular, and may be completed in the second spring Collecting time May to September Auxin concentration 0.5 % Rooting rates are usually over 80%, although high in dividual variation should be expected if working with a large number of clones (Cervelli, 2005; Piccioni et al., 1996; Pignatti and Crobeddu, 2005). Micropropagation of V. tinus has been carried out suc cessfully by Nobre et al., (2000) using internodal seg ments of young plants. Herrera CM (1998) Longterm dynamics of Mediterranean fru givorous birds and fleshy fruit: a 12year study. Ecological Monographs 68:511538 Karlsson LM, Hidayatu SN, Walck JL, Milberg P (2005) Complexe combination of seed dormancy and seedling devel opment determine emergence of Viburnum tinus (Caprifoli aceae). Annals of Botany 95: 323330 Lamb JG, Kelly JC (1988) Propagating viburnums. Plantsman 10:101103 Nobre J, Santos C, Romano A (2000) Micropropagation of the Mediterranean species Viburnum tinus. Plant Cell Tissue and Organ Culture 60:7578 Piccioni E, Longari F, Standardi A, Ciribuco S (1996) Propaga zione per talea e allevamento in vaso di alcune specie arbus tive. Informatore Agrario 52:8791 Pignatti G, Crobeddu S (2005) Effects of rejuvenation on cut ting propagation of Mediterranean shrub species. Foresta 2:290295 (online URL http://www.sisef.it/) Winkworth RC, Donoghue MJ (2005) Viburnum phylogeny based on combined molecular data: implications for taxon omy and biogeography. American Journal of Botany 92:653–666 137 Viburnum tinus Nursery production Vitex agnuscastus L. Distribution and Ecology Distribución general: Southwestern, Southeastern and Eastern Europe, Caucasus, Western and Middle Asia, Northern Africa Mediterranean region: Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel, Tunisia, Al geria, Morocco Diagnostic traits The chaste tree is a deciduous shrub or small tree that does not usually exceed 4 to 5 m in height. It is the only species of its genus that grows naturally in Eu Reproductive biology Sex expression ■ hermaphroditism Flowering Vitex agnus-castus 138 bluish, rarely white, flowers, clustered in superimposed cymes forming a long panicle ■ from June to September ■ Verbenaceae EN: vitex, chastetree EL: λυγαριά, λυγιά ES: sauzgatillo, agnocasto FR: gattilier, poivre des moines IT: agnocasto, lagano, aino PT: agnocasto, árvore da castidade Pollination ■ This is a thermophile species that occurs in the form of isolated specimens in willow and oleander formations next to rivers and temporary watercourses, occasionally giving rise to very dense, more or less pure stands. Al though V. agnuscastus is a typical Mediterranean species it does not grow in especially dry areas, as it requires a certain level of environmental humidity. It prefers well drained soils and cannot withstand high salinity. rope. Its leaves are opposite, petiolate and compound palmate with five to seven linear lanceolate leaflets. entomophilous Fruiting Ripening ■ ■ blackish, globose drupe ■ 34 mm from October to December ■ dispersal by frugivorous vertebrates Variation and Hybridisation There is no information on intraspecific variation and hybridisation for this taxon. Seed propagation Seed handling and storage Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ autumn gathering by hand sequence for indehiscent dry fruits ■ seed weight / kg fruit: 750 g ■ purity: 80 % 713 g Germination under controlled conditions Pregermination treatments ■ prechilling (12 weeks) Nursery production Sowing season ■ autumn, without treatment or spring, with treatment Vegetative propagation Type of cutting ■ ■ hardwood semihardwood Position along the shoot indifferent indifferent Conditions ■ ■ Germination Viability 30 / 20 ºC light ■ Nursery practice ■ Number of internodes Size Chastetree is readily reproduced by vegetative propa gation from cuttings collected in winter as well as in summer (Dirr and Heuser, 2006; Mac Carthaig and Spethmann, 2000). 6070 % Emergence forestpot 300 cm3: 1/0 or 2/0 15 cm 23 T: 4 ºC MC: 48 % ■ airtight container ■ ■ the first spring Collecting time winter summer Auxin concentration none or < 0.5 % none or < 0.5 % Economou et al. (2000) and Varma et al. (1991) have reproduced this species by in vitro cultivation of axillary buds. 139 Vitex agnus-castus Tolerance to desiccation: ORTHODOX References General references Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Tutin TG (1972) Vitex L. In: Tutin TG et al. (eds). Flora Euro paea. Vol 3. Cambridge University Press, Cambridge Young JA, Young CG (1992) Seeds of woody plants in North America. Dioscorides Press, Portland Specific references Dirr MA, Heuser CW (2006) The Reference Manual of Woody Plant Propagation: From Seed to Tissue Culture. A Practical Working Guide to the Propagation of over 1100 Species, 2nd. ed. Varsity Pr Inc, Athens Economou A, Hatzilazarou S, Karahalios V, Ralli P (2000) Pro pagation of Vitex agnuscastus by tissue culture. Acta Horti culturae 541:147151 Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Gehölzvermehrung. Parey Buchverlag, Berlin Varma PN, Vikramaditya, Sarka M (1991) A preliminary report on the in vitro culture of Vitex agnuscastus. Journal of Eco nomic and Taxonomic Botany 15:687694 Vitex agnus-castus 140 General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Caucasus, Western and Middle Asia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Diagnostic traits The wild grapevine is a deciduous, woody climber that can reach 30 m in height. In old stems, the bark peels off in long shreds. Its leaves exhibit wide variations within the same individual but are normally palmately lobed, more deeply so in male plants. It is commonly a Reproductive biology ■ dioecy Flowering greenish flowers, clustered in panicles ■ from April to June ■ Pollination ■ Turkey, Syria, Lebanon, Israel, Tunisia, Algeria, Morocco This is a typically Mediterranean species that is found on cool soils, preferably as a climber on trees and shrubs in riverside areas and groves. It also grows in leafy woods and colonises rocky areas and slopes in cooler climates. dioecious taxon although hermaphrodite flowers have been reported in some cases (Failla et al., 1992). This trait distinguishes this taxon from cultivars, which pro duce hermaphrodite flowers. entomophilous Fruiting Ripening ■ ■ red or black, globose or ellipsoidal berry ■ 58 mm from September to November ■ dispersal by frugivorous vertebrates 141 Vitis vinifera Distribution and Ecology Sex expression Vitis vinifera L. subsp. sylvestris EN: wild vine EL: αμπέλι, κλήμα ES: parra borde, vid salvaje FR: lambrusque, vigne sauvage IT: vite selvática PT: labrusca, videira brava Vitaceae Variation and Hybridisation Accurate determination of the range of distribution of this species is difficult, since its domestication began between 2500 and 2000 BC. Archaeobotanical studies seem to show that domestication of the wild grape vine took place independently in the eastern and west ern areas of what is believed to be its natural distribution range (Núñez and Walker, 1989), which would imply that it was native to both regions. This hy pothesis has been confirmed by comparative studies which have used molecular techniques to analyse ma terials from different points of the distribution range. Such studies have revealed genetic differences between western and eastern populations (Imazio et al., 2003; ArroyoGarcía et al., 2006), possibly because these pop ulations originated along different colonisation routes after the glaciations (Imazio et al., 2003). Furthermore, molecular studies of local grapevine cultivars from dif ferent European regions have pointed to a correlation between genetic distance and geographical distribu tion, suggesting that grapevine domestication basi cally took place in situ, mainly using local wild specimens (Sefc et al., 2003; ArroyoGarcía et al., 2006). Even if cultivars were introduced, they must have undergone very strong introgression from local wild provenances (Sefc et al., 2003). In any event, fos sil grapevine leaves found in southeast France which date from about 6900 BC (Roiron et al., 2004) are evi dence of the spontaneous occurrence of the species in its western distribution range. The existence of genetic differences between regions makes it advisable to exercise caution when collect ing and using reproductive materials, which should be of local provenance whenever possible. Such precau tions are further underscored by the existence of adaptations to cold and drought (Sefc et al., 2003) which make it inadvisable to introduce cultivars from other climates. The wild grapevine was already a threatened species by the middle of the 19th century, when pests like phyl loxera developed. It has also suffered the constant de struction of its habitat (Arnold et al., 1998; López et al., 2004). Today it is difficult to find pure populations of V. vinifera subsp. sylvestris, as they are often found to be a mixture of wild stock, cultivars, rootstock varieties of American species and hybrids of all these (Sefc et al., 2003). The wild grapevine is particularly threat ened in some natural populations with low levels of ge netic variation, possibly as a result of habitat destruction and a reduction in the number of individ uals (Imazio et al., 2003). In fact, populations of this species do not generally exceed ten individuals and in some cases are made up of specimens of only one sex (Arnold et al., 1998). It might therefore be of interest to use the species in hydrological restoration projects, in such a way as to reverse the trend towards reproduc tive isolation of populations and thereby decrease their degree of discontinuity. Seed propagation Seed handling and storage Tolerance to desiccation: ORTHODOX Collecting Cleaning 1,000 seed weight Storage ■ ■ ■ ■ ■ autumn gathering by hand or using longhandled tools sequence for fleshy fruits seed weight / kg fruit: (data not found) ■ purity: (data not found) ■ 31 g T: 4 ºC MC: 8 % ■ airtight container ■ Vitis vinifera 142 Germination under controlled conditions Pregermination treatments ■ prechilling (812 weeks) Conditions ■ ■ 30 / 20 ºC; 30 / 15 ºC; 25 ºC light Germination Viability ■ (data not found) Coldstratification time can be reduced if seeds are treated with a 1,000 ppm solution of gibberellic acid for 24 hours (Ellis et al., 1983). Sowing season ■ autumn, without treatment, or spring, with treatment Vegetative propagation Type of cutting ■ hardwood Position along the shoot basal or middle Nursery practice ■ forestpot 300 cm3: 1/0 or 2/0 Number of internodes Size 20 30 cm Traditionally, hardwood cuttings are used for vine multiplication. The material is normally harvested be tween December and January and stored temporarily. In the spring, when the temperatures begin to rise (Muñoz and Villalobos, 1976), the cuttings are planted after overnight rehydration (Alley and Christensen, 1974; Balo and Balo, 1968). The effects of rooting hormones vary greatly between individuals and in some cases can even have negative effects (Alley, 1979). It is also possible to propagate vines in sum mer, using softwood cuttings from one to two intern odes in length (Muñoz and Valenzuela, 1978; Stefanini and Iacono, 1998; Thomas and Schiefelbein, 2004). Mac Cárthaig and Spethmann (2000) recom mend the use of bud cuttings. The material is col lected in late November and stored until it is Emergence ■ (data not found) Collecting time DecemberJanuary Auxin concentration < 0.1 % processed and planted in February. In this technique, the bestdeveloped lateral buds are chosen and the upper and lower internodes are cut through transver sally at a distance of 1.5 to 2 cm from the bud. In the opposite side of the stem from the bud, a sloping cut is made lengthwise from top to bottom. It is recom mended that cuttings be treated with 1% indolbutyric acid. The cuttings are then planted at a slight angle, leaving only the bud protruding from the substrate, in boxes containing a mixture of peat and sand. Vines can also be propagated by layering. The methods for in vitro propagation of vines are well developed. Stem segments with a lateral bud are often used as explants. (Mhatre et al., 2000; Singh et al., 2004). 143 Vitis vinifera Nursery production References General references Ellis RH, Hong TD, Roberts EH (1985) Handbook of Seed Tech nology for Genebanks Volume II. Compendium of Specific Germination Information and Test Recommendations Hand books for Genebanks: No. 3. IPGRI, Rome Piotto B, Di Noi A (eds) (2001) Propagazione per seme di al beri e arbusti della flora mediterranea. ANPA, Roma Webb DA (1968) Vitis L. In: Tutin TG et al. (eds). Flora Euro paea. Vol 2. Cambridge University Press, Cambridge SSR analysis. Proceedings of the Eighth International Confer ence on grape genetics and breeding. Acta Horticulturae 603:4957 López MA, Ocete R, Gallardo A, Cantos A, Troncoso A (2004) Ecological aspects and conservation of wild grapevine popu lations in the S.W. of the Iberian Peninsula. Acta Horticulturae 652:8185 Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Specific references Mhatre M, Salunkhe CK, Rao PS (2000) Micropropagation of Vitis vinifera L. towards an improved protocol. Scientia Horti culturae 84:357363 Alley CJ (1979) Grapevine propagation. XI. Rooting of cuttings: Effects of indolebutyric acid (IBA) and refrigeration on roo ting. American Journal of Enology and Viticulture 30:2832 Muñoz IH, Valenzuela JB (1978) Rooting capacity of softwood cuttings in three grape cultivars: Effect of the position on the cane and time of collection. Agricultura Técnica 38:1417 Alley CJ, Christensen LP (1974) Rooting of ‘Thompson See dless’ Cuttings. V. Rooting of Fresh and Stored Cuttings when Cut November to April. American Journal of Enology and Vi ticulture 25:168173 Muñoz IH, Villalobos AP (1976) Enraizemiento de estaces de vid. I. Capacidad natural de dos especies de Vitis, efecto de ubicacion en el sarmiento y de epoca de recoleccion. Agricul tura Técnica 36:2530 Arnold C, Gillet F, Gobat JM (1998) Situation de la vigne sau vage Vitis vinifera ssp. sylvestris en Europe. Vitis 37:159170 Nuñez DR, Walker MJ (1989) A review of palaeobotanical find ings of early Vitis in the Mediterranean and of the origin of cultivated grapevines, with special reference to new pointers to prehistoric exploitation in the Western Mediterranean. Re view of Paleobotany and Palynology 61:205237 ArroyoGarcía R, RuizGarcía L, Bolling L, Ocete R, López MA, Arnold C, Ergul A, Söylemezoğlu G, Uzun HI, Cabello F, Ibáñez J, Aradhya MK, Atanassov A, Atanassov I, Balint S, Cenis JL, Costantini L, Gorislavets S, Grando MS, Klein BY, McGovern PE, Merdinoglu D, Pejic I, Pelsy F, Primikirios N, Risovannaya V, RoubelakisAngelakis KA, Snoussi H, Sotiri P, Tamhankar S, This P, Troshin L, Malpica JM, Lefort F, MartínezZapater JM (2006) Multiple origins of cultivated grapevine (Vitis vinifera L. ssp. sativa) based on chloroplast DNA polymorphisms. Mo lecular Ecology 15:3707–3714 Balo E, Balo S (1968) Connection between the water level during soaking and the water level of cuttings and their rooting when planted in nurseries. Szoeloees Gyuemoelcsterm 4:183188 Failla O, Anzani R, Scienza A (1992) La vite selvatica in Italia: diffusione, carateristiche e conservazione del germoplasma. Vignevini 1/2:3746 Imazio S, Grassi F, Scienza A, Sala F, Labra M (2003) Vitis vinifera ssp. sylvestris: the state of healt of wild Italian and Spanish populations estimated using nuclear and chloroplast Roiron P, Ali AA, Guendon JL, Carcaillet C, Terral JF (2004) Preuve de l’indigénat de Populus alba L. dans le Bassin médi terranéen occidental. Comptes Rendus Biologies 327:125132 Sefc KM, Steinkellner H, Lefort F, Botta R, Da Câmara Machado A, Borrego J, Maletić E, Glössl J (2003) Evaluation of the gene tic contribution of local wild vines to European grapevine cul tivars. American Journal of Enology and Viticulture 54:1521 Singh SK, Khawale RN, Singh SP (2004) Technique for the rapid in vitro multiplication of Vitis vinifera L. cultivars. Jour nal of Horticultural Science and Biotechnology 79:267272 Stefanini M, Iacono F (1998) Nuove tecnologie per la produ zione di barbatelle. Informatore Agrario 54:5356 Thomas P, Schiefelbein JW (2004) Roles of leaf in regulation of root and shoot growth from single node softwood cuttings of grape (Vitis vinifera). Annals of Applied Biology 144:2737 Vitis vinifera 144 3 147 Appendices Variation and adaptation Trees possess hereditary systems that resemble those of other living organisms. The variation we see both be tween species (interspecific) and within species (in traspecific) is attributable to two main causes: environmental conditions, which have long been known to man and are the basis for forestry activities, and the genetic makeup of individuals, which is fre quently ignored. However, this latter source of variation is so important that we may say that no two trees are the same. Forests develop in highly heterogeneous environments, in terms of both space and time, and generally exhibit a wide range of genetic variation, both geographically (between populations) and locally (within populations). The transmission of this variation from one generation to the next and its variability ensure the continuous evolution of species and populations (Morgenstern, 1996). Geographical origin is one of the most relevant levels of genetic variation between trees, since it de Factors determining genetic variation The evolution of riverside forests does not depend solely on genetic heritage and on the surrounding environ ment, but is also influenced by human activity. Ecosys tem fragmentation is one of the main and most common manmade changes, altering local conditions and causing the isolation of tree populations. Reduc tions in the area of the remaining local populations, together with their increased spatial isolation and the decrease in the number of reproductive individuals per unit of surface, can affect genetic processes such as the flow of pollen, fruits and seeds, crossfertilisation and naturalselection efficiency; all of which are fac tors that determine the degree and pattern of distri bution of genetic diversity among species (Young, 1995). The viability of these populations can be com promised as a result of disturbances in their reproduc tive processes and a loss of adaptability, which is very often associated with a loss of genetic variation. Population evolution also depends on the gene flow taking place through pollen or seed migration, which attenuates the effect of selection and influences the effective population size (Ne). When populations are very small and gene flow is low or totally absent, chance may prevent individuals from adapting to envi termines adaptability (Zobel and Talbert, 1984; Müller Starck, 1991). The genetic quality of forest reproductive materials is often not taken into account in ecosystem restoration activities, including riparian habitat recovery projects; cheaper seeds and plants are used without due regard for their origin. These practices are revealed as partic ularly mistaken when we consider the climate changes that have been taking place in the Mediterranean re gion in recent decades. Such changes have led to an aggravation of environmental conditions due to an in crease in temperatures, a significant drop in springtime rainfall levels and an increase of interannual variations in winter rains. Practice has shown that the use of plants that are adapted to local conditions is one of the factors that have a positive influence on the suc cess of forestation and on the evolution of new popu lations, which grow and develop dynamically in a process of interaction with their environment. ronmental conditions (Wright, 1976; Zobel and Talbert, 1984). In Figure 1, subpopulations A’ and A” are the result of a not too severe fragmentation of a former population A. Here, gene flow has not been prevented and the ge netic differentiation is lower than in subpopulations B’ and B”, shown in Figure 2, which have resulted from the fragmentation of a riparian population B. Gene flow between B’ and B” has been limited by the geo graphical distance that sets them apart. In this case, genetic differentiation is a function of the distance be tween the two subpopulations. The effect of this dis tance may be attenuated by the watercourse, which provides a transfer route for fruits and seeds, or even parts of plants. On the other hand, the small size of subpopulation B” would have a direct effect on the number of individuals taking part in the reproductive process. If gene migration is insufficient, population B’’ will tend to undergo a dramatic decrease in variation as a result of random loss of genes (genetic drift). This could gradually become more marked in successive generations, due to depression through inbreeding. These two factors, drift and inbreeding, might induce a lower degree of adaptability in subpopulation B”. 149 Variation and adaptation Reproductive materials and adaptability Figure 1 Fragmentation undergone by a primitive population A, divided into two subpopulations of similar size, with a distance between them that allows gene flow. Figure 2 Fragmentation undergone by a primitive population B leading to two populations – one of which is very small – separated by a considerable distance. Variation and adaptation 150 The spatial structure of these populations increases the fragility of riverside forests, especially in the case of dioic species or vegetatively propagated species, where a group of trees that are close together may all be of a single genotype. Genetic quality of reproductive materials An issue that frequently arises is the minimum number of trees from which material must be collected to pre serve adequate genetic variation in new populations. Eriksson et al. (1995) report that, in a given population, fifty unrelated individuals are enough to capture the genetic variants that are most common and presum ably offer adaptive advantages over other less frequent variants. Reproductive materials should thus be col lected from individuals that are separated by a certain References Eriksson G, Namkoong G, Roberds J (1995) Dynamic Conser vation of Forest Tree Gene Resources. Forest Genetic Re sources, 23:28 Morgenstern EK (1996) Geographic Variation in Forest Trees: Genetic Basis and Application of Knowledge in Silviculture. UBCPress, Vancouver MüllerStarck G (1991) Survey of genetic variation as inferred from enzyme gene markers. In: MüllerStarck G, Ziehe M (eds). Genetic Variation in European Populations of Forest Trees. JD Sauerländer, Frankfurt distance, which in practice is about fifty to one hun dred metres, in order to minimise kinship relations. Collection of materials from many individuals is par ticularly important in order to ensure a wide genetic base. In the case of vegetative propagation species, the use of a limited number of clones with high rooting rates can be convenient from the practical and cost point of view but makes the adaptability of the result ing new populations unpredictable. Identifying popu lations with a significant number of welldeveloped, healthy individuals is of the utmost importance, since the areas in which they are found will be potentially good sites to collect materials. Funding of forestation projects on private property through regional, national or European Community ini tiatives and the efforts of public institutions with re gard to certification processes for forest reproductive materials contribute to more responsible action and to marketing seeds and plants that meet appropriate quality standards in compliance with the law. European Union directive 1999/105/EC highlights the importance of forest reproductive material quality in relation to the stability, adaptation, resistance and productivity of forests. In the short term, adequate implementation of these standards involves good management of mate rialproduction areas with a view to covering market demands through the skilful use of handling and prop agation techniques. Wright JW (1976) Introduction to Forest Genetics. Academic Press, New York Young A (1995) Forest Fragmentation: Effects on Population Genetic Processes in Caring for the Forest: Research in a Changing World. In: Koorpilahti E, Mikkelä H, Salonen T (eds). Proceedings of IUFRO XX World Congress, vol. 2, Tampere, Finland Zobel B, Talbert J (1984) Applied Forest Tree Improvement. J. Wiley & Sons, Inc., New York 151 Variation and adaptation Delimitation of regions of provenance is a procedure that allows reproductive materials to be characterised with a view to promoting their adaptation to planta tion areas. This system has been adopted for a great many forest species. The delimitation is based on envi ronmental and genetic parameters that make it possi ble to identify the populations that are best suited to each different area. This requires knowledge garnered from trials and studies, which have already been con ducted for many decades in the case of certain species. However, the genetic variation and adaptability of most riverside trees are not known and regions of prove nance at species level have therefore not been deter mined. Furthermore, limited production of plants of these species in local and regional nurseries in the Mediterranean region, and at a higher price than in other production areas, is one of the factors that en courage the use of plants of inappropriate origin in riverine forestation operations. Seed handling Seed handling and storage One of the decisive phases for the quality of reproduc tive materials and, consequently, for the success of the plant production phase, is the treatment they receive between collection and storage for future use. Fruits and seeds are living, perishable matter and should therefore be handled with care; whatever damage is caused might be irreversible and in most cases will cer tainly affect quality. Seed lot quality will depend not only on factors that have to do with the material it self, which is difficult to control, but also on aspects which are more controllable, such as the presence of microorganisms, insect attacks and mechanical and physiological damage during handling and storage. Once they have been harvested, the materials must be transported as quickly as possible to the processing fa cility, avoiding direct heat and mechanical damage and making sure that labelling is adequate at all times in order to ensure correct lot identification. Seeds and fruits are transported in paper or cloth bags, or in sacks made of jute or plastic mesh in the case of large volumes. Seed handling and storage involve a series of sequen tial processes (Figure 3), which require the application of different methods, as well as the control of environ mental conditions, which vary depending on the type of fruit and seed. collecting fruit processing packaging storage plant production testing periodic testing conservation seed processing cleaning and conditioning preprocessing storage pregermination treatments sowing Figure 3 Sequence of activities from collecting to sowing Seed handling 152 One of the most important aspects to bear in mind is the degree of desiccation tolerance of the seeds. One group of species has seeds that are called recalcitrant because they lose viability if their moisture content falls below a relatively high threshold, which varies by species (Quercus, Aesculus, Castanea, Corylus or a great variety of tropical taxa). Many other seeds, known as orthodox, can stand moisture levels of less than 10% and may be kept in cold storage for many years. There are also seeds that display intermediate behaviour and are classified into what is known as the suborthodox group, which includes Juglans, Caria and Fagus and some riparian taxa like Populus, Salix and Ulmus. Once the material has been taken to the processing fa cility, operations should begin as soon as possible. Seeds must be weighed and visually inspected to detect the presence of fungi and insects so that lot handling priority may be determined and the necessary meas ures can be taken. At this stage, the material should be kept in the shade, in a cool place or in a coldroom, especially when it has to wait a few days before cleaning begins. In the case of recalcitrant seeds, this stage should be as short Extraction and cleaning The harvested material never arrives pure from the field, so it must be cleaned to rid it of debris. Seed ex traction and cleaning tasks are generally laborious, al though some species require greater effort than others, especially when no specific mechanical means are available for this kind of work. From the practical point of view, the methods used to obtain a seed lot of suitable external quality depend to a great extent on the shape and size of the material. The processing stages and the methods employed for each different species must be based on separation ef ficiency: impurities must be eliminated without loss of viable seed and cleaning work should be minimised to reduce damage potential and costs. Preliminary cleaning When the material is fruits that must be processed for seed extraction, preliminary cleaning is usually per formed by flotation or by manual or mechanical siev ing, both to eliminate large debris and other impurities as possible and special care must be taken to avoid both moisture content loss and the proliferation of fungi. In general, it is also advisable to shorten the stor age time of fleshy fruits, in the meantime making sure that they do not lose moisture while at the same time avoiding fermentation. Dryfruit species and orthodox seeds can be dried out gradually; in some cases it is ad visable to give them a preliminary airing to allow the seed to ripen (Fraxinus angustifolia, F. excelsior), or to ensure initial drying in the case of fruits that are to be opened by heating. Seeds of trees and shrubs normally used in Mediter ranean afforestation projects can be grouped into four large categories for the purposes of establishing com mon extraction and cleaning protocols (Figure 4): seeds that need not be extracted from their fruits (Acer, Fraxinus, Quercus, Ulmus) seeds in capsules and indehiscent dry fruits (Cistus, Colutea) seeds in cones and dehiscent fruits (Pinaceae, Cu pressus, Tetraclinis, many Fabaceae, Alnus, Atriplex, Betula, Carpinus, Carya, Casuarina, Eucalyptus, Fagus, Liquidambar, Platanus, Populus, Tilia) seeds in fleshy strobili and fruits (Caprifoliaceae, Rosaceae, Rhamnaceae, Oleaceae, Juniperus, Taxus, Cornus, Ribes) and also to separate and collect seeds that may have fallen free during transport and temporary storage of the lots, as may be the case with cones and dehiscent fruits. 153 Seed handling Temporary storage Seed handling 154 fruit opening dry dewinging final drying washing liquid separation (recalcitrant: surface only) final drying sifting blowing sifting blowing (recalcitrant) cleaning drying liquid separation final drying (recalcitrant: surface only) sifting blowing dry dewinging drying wet dewinging sifting blowing cleaning seed extraction (cold: orthodox and recalcitranthot: some orthodox) (except recalcitrant) fruit drying cones and dehiscent dry fruits fruits that can be sown sifting blowing cleaning fruit cracking fruit drying indehiscent dry fruits and seeds in capsules Figure 4 Suggested sequences for handling seeds (some steps may not be necessary for each lot; final drying may not be essential for immediate stratification or sowing) final drying sifting blowing drying washing liquid separation cleaning depulping maceration fleshy fruits In some cases the seeds need not be extracted from the fruits, which can be sown directly. However, in most species extraction is necessary, since the fruit could be a physical impediment to germination or could contain germination inhibitors; it is also necessary to avoid rotting in the case of fleshy fruits. Fruits can be opened manually by splitting the coat, with the aid of pincers, rubber mallets, lancets or other tools if necessary. This is an intensely laborious method and is usu ally only employed with very small lots. Mechanised crush ing is done with different kinds of threshers and other mechanical tools, or with kitchen utensils such as grinders or blenders that have been adapted for the purpose. Dehiscent fruits and cones can be opened through spon taneous drying and opening, by spreading the material out in thin layers under cover or in the sun. Forced hotair ventilation or a kiln with controlled temperature and moisture can also be used for some species. Al Fractioning though Mediterranean species are well adapted to the heat, a temperature of 30 to 40ºC should not be ex ceeded and fluctuations in the moisture content of the seeds should be avoided. To ensure this, the materials must be protected from the rain and if they are spread out to dry the seeds should be collected as the fruits open. The use of perforated trays, to retain the fruit and let the seeds gradually drop through, can make subse quent cleaning easier. In the case of fruits with explosive dehiscence, like some leguminous taxa, they should be covered to avoid scattering. It is sometimes necessary to shake the material after it opens in order to extract seeds that may still remain within the open fruit; this can be done manually or by using tumblers of different sizes, depending on the volume of material being processed. The pulp of fleshy fruits can be removed by manual rub bing, using a sieve or a bag, after soaking the material in water. Sand can be added to increase friction. Mechani cal instruments such as mixers or shakers are also used. This stage eliminates fruit remnants, infected, damaged and unviable seeds and other inert matter. In some species, wings must also be discarded. This step helps to reduce the size and heterogeneity of seed lots, optimises sam pling, increases testing reliability and facilitates sowing. to use flotation, or to place the material in sieves and wash it with pressurised water. Facilities that process many seed lots or large seed lots use specially designed machinery, including scalpers, blowers, aspirators, de bearders, indented cylinders and gravity tables. Cleaning methods are based on external characteristics and on the physical properties that differentiate seeds from impurities: size, length, shape, colour, density, tex ture or rate of fall. There are many cleaning methods, including visual inspection, screening or sieving, win nowing, and flotation. Cleaning equipment varies ac cordingly and may be manual or mechanical, adapted for small or large volumes and different types of seed. This equipment can be used alone or in combination to improve lot quality throughout the cleaning process. In some species, wings must be removed from the seeds (Pinus, Abies). In some others this is not strictly necessary but may be done in order to reduce lot volume, as in the fruits of Fraxinus, Liquidambar or Acer. There are several dewinging methods, ranging from the simplest, such as manual rubbing in cloth sacks, to mechanical systems using debearders, or rotating containers in the case of large lots, that can carry out dewinging either dry or wet. The simplest tools are manual screens or sieves, which are normally used in a sequence of increasingly large or small mesh sizes. For some species it is more practical After wet processes like depulping or flotation frac tioning the seeds must be dried gently for a short pe riod of time before handling continues. It is advisable to clean the sieves and machinery after processing each seed lot. 155 Seed handling Fruit opening Drying The moisture content of preserved seeds is of great im portance, since it has a direct influence on longevity. Re calcitrant seeds must only be dried briefly, spread out in a cool area, to rid them of excess surface water. Ortho dox seeds can be air dried in a cool, shaded place if no appropriate purposemade facility exists. In any event, direct sunlight, hot air or central heating is not recom mended. If a drying room is available, it should be kept at a temperature of 15 to 20 ºC and a relative humidity Testing It is advisable to test seed lots to ascertain whether their moisture contents are suitable for storage and to determine their external quality in terms of germina tion capacity or viability, purity and seed size. These test results will indicate whether the lot should be dis carded, improved by more cleaning, or may be stored as it is. The values determined by the tests will also give an idea of expected performance during the plant pro Storage As with drying, storage conditions depend on the des iccation tolerance of the seed. Recalcitrant seeds are kept in porous bags such as cloth, jute or plasticmesh sacks, or in perforated plastic containers that allow for air circulation. They are usually mixed in with inert ma terials, like peat, coconut fibre, sawdust or vermiculite, which are maintained at moisture levels similar to those of the seeds. In environments that are not specif ically controlled, it is advisable to moisten the seeds frequently, although they will rapidly lose their viabil ity in such conditions. In controlled environments they must be kept at relative humidity levels of 85 to 90 %, of 15 to 25 %. In these conditions, the seeds of a great many species reach a moisture content that is quite suit able for storage. When working with small seed lots, small drying rooms can be used; silica gel is placed in the rooms and gradually replaced as it changes colour. Seeds should be spread out on trays, in thin layers, to allow for air circulation. Conventional drying limits for orthodox seeds range from 5 to 10 % moisture content, although it may sometimes reach 15 %. duction stage. If the necessary facility is not available there are laboratories, both official and private, that provide this kind of service. When sampling and test ing lots, it is advisable to follow the standardised pro tocols that make it possible to compare the results of different lots. In Europe, the protocols most commonly used are the International Seed Testing Standards of the International Seed Testing Association (ISTA). at a temperature of –3 to 0 ºC for temperate species; this will preserve seed viability for 1 to 2 years. When relative humidity in the place of storage is not controlled, orthodox seeds must be kept in airtight re ceptacles made of metal, plastic or glass. If appropriate facilities are not available, it is advisable to keep these containers in a cool, dry place, protected from sunlight. If coldrooms are available, the conventional storage temperature is 4 to 5 ºC, and up to –4 ºC for some species. For longterm conservation, the seeds of many species can be kept at –18 ºC. Seed handling 156 The seeds of many species germinate without difficulty in favourable temperature and humidity conditions. Sowing in a nursery during the appropriate season or subjecting seeds to defined conditions in an incubator – after soaking in water for 24 to 48 hours if the seeds are dehydrated – is enough to obtain good perform ance from lots with a high percentage of viable seeds. However, many species have dormant seeds that need to be pretreated before they can germinate. The meth ods most commonly employed to break dormancy are as follows: mechanical scarification: this method is used to allow water to penetrate seeds with an impermeable coat. The seed coat is cut or abraded using manual tools such as files, small pliers, knives or mechanical scar ifiers. If treatment is manual, the ideal application site to avoid damaging the embryo is the part of the seed coat that is located just over the tips of the cotyledons. chemical scarification: the seeds are soaked in a 95% sulphuricacid solution at room temperature (18 to 27 ºC). The treatment period will depend on the de gree of impermeability of the seeds, which varies ac cording to the species, the lot, and any treatment applied when handling the material. If the seeds have been kept in cold storage, it is advisable to first let them return to room temperature. After treating the seeds with acid, they must be washed carefully with plenty of running water for 5 to 10 minutes. This treatment is also designed to let water penetrate the seed coats more easily. soaking in water: the seeds are placed in a water bath at an initial temperature of 80 to 100 ºC and left to cool gradually. The volume of water should be 2 to 10 times greater than that of the seeds. This method is also used to increase seed coat permeability. cold stratification and hot stratification: cold stratifi cation requires keeping the seeds moist, at a tempera ture of 2 to 5 ºC, in an environment that allows a certain degree of air circulation. The seeds are hydrated for 24 to 48 hours and placed between layers of a moist, inert substrate (peat, sand, vermiculite, etc.). Containers should be covered to avoid loss of moisture, but care must be taken to ensure adequate air circula tion. They are then left at the required temperature for the necessary length of time. Stratification is also pos sible without a substrate, by placing the moist seeds in plastic bags, Petri dishes or other containers which must be opened periodically to let in some air. However, stratification in such containers should be carried out with great care in order to avoid not only seed desic cation but also the proliferation of fungi, especially in the case of long treatment periods. This type of cold stratification often makes it possible to break a dor mancy which is due to physiological causes. When mor phological dormancy is present in the seeds, in species in which the embryo has not developed at the time of fruit ripening, it may be advisable to apply hot stratifi cation before cold stratification in order to stimulate embryo development. Hot stratification is also carried out in a moist environment, but at a temperature of no more than 30 to 35 ºC; 15 to 20 ºC is normally enough. use of hormones and other chemical compounds: some cases require the use of hormones or com pounds such as gibberellic acid (GA3) or ethylene, or other substances that have a positive or stimulating effect on germination. These products should be em ployed at appropriate concentrations for periods of time that are not harmful to the seeds. 157 Seed handling Pregermination treatments Nursery culture Nursery cultivation regime Generally, each nursery develops a system of cultivation based on its own experience, which leads to different, sometimes very different, cultivation regimes for the same species depending on the nursery in question. Al though this is inevitable, since each nursery has its own particular characteristics, it is also necessary for the various systems to result in a final product which is rel atively uniform and in accordance with a specific qual ity of plant for a particular purpose. To this end, the nursery needs to know the influence of the different cultivation variables on the development and final quality of each species. Therefore, the main variables in nursery cultivation and the basic relationship of each with plant development need to be identified. Each variable of the nursery cultivation system must be considered individually in relation to the whole regime. The variables or, rather, the groups of variables which define the cultivation of plants in containers are: forest reproductive material (seeds, cuttings, etc.), en Environmental conditions The environmental conditions to be managed in nurs eries are temperature, humidity and light (CO2 can also be controlled). Substrate temperature plays a role in the absorption of water and transpiration and the as similation of essential nutrients. Environmental tem perature (and its diurnal variation or periodicity) affects metabolic processes such as photosynthesis and respi ration and biophysical processes such as transpiration (Landis et al., 1992). Also of interest are the degree of light (affects plant growth), its intensity (required to stimulate photosynthesis and prolong active growth), its duration (involved in the induction of dormancy), and its quality (different wave lengths activate differ ent plant functions) (Landis et al., 1992). Containers Nursery culture 158 The receptacle or container is one of the variables with more obvious effects on the crop. The size of the con tainer (volume, height, diameter and shape) and its den sity (number of cells per unit area) are the two basic factors that control plant growth in nurseries as well as the possible posttransplant response (Landis et al., 1990a). Low density containers control the balance be tween the aerial and radical parts of the plant better, thus vironmental conditions, containers, substrates, fertil ization, irrigation and pest and disease control (Bris sette et al., 1991; Landis et al., 1989, 1990a, 1990b, 1992, 1994, 1998; Peñuelas and Ocaña, 1996). The cultivation regime for a species, a group of species, or plants of a particular type consists of a definition of the groups of characteristics or classes to be satisfied by these variables, giving a detailed description of each and of plant development throughout the regime (Lan dis et al., 1998). These features should be included in a calendar or overall schedule of the cultivation regime, which in its simplest version is a chart of the condi tions to be maintained and operations to be carried out in the nursery from planting until the eventual release of the plant (Brissette et al., 1991). The growing period is divided according to the different stages of plant de velopment in the nursery, normally restricted to three: the germination and/or establishment phase, the ac tive (or rapid) growth phase and the hardening phase. The climatic conditions of the area in which the nursery is located will have a determining influence on the type of cultivation and the planting timetable. The most com mon facilities for controlling environmental factors are greenhouses and shade screening. Providing shade re sults in decreased levels of radiation (preventing possi ble leaf burning), reduced air and leaf temperatures (enhancing photosynthesis), lower substrate tempera tures (reducing irrigation requirements) and altered shoot/root ratio relationships, which can cause morpho logical imbalances (Svenson, 2000). Some species can be grown without shade while others need some protec tion (especially in the early stages of cultivation) to avoid possible damage to the photosynthetic system. preventing the tendency of some species to grow tall and branchless due to the density of planting. Another im portant aspect of the container is its influence on the sub strate properties, especially its waterretention capacity (Ansorena, 1994). Further considerations are that the con tainer should avoid root malformations by means of anti spiralling systems, encourage good aerial root pruning and have sufficient depth for deeprooting species. The substrate supplies water, air, nutrients and support to the plant and determines the practical implementa tion of other important variables such as irrigation and fertilization (Landis et al., 1990a). Not without reason is it said that this is the main factor which determines the success of cultivation in containers (Ansorena, 1994). In general, the composition of substrates used in both horticulture and forest cultivation is mainly peat, to which an aerator component such as perlite or ver miculite is added (Fonteno, 1993; Burés, 1997). In ad dition to these components, nurseries often use pine bark, sand, Litonita, topsoil or mulch, whose properties and characteristics are well reflected in the literature (Burés, 1997). Irrigation Unlike containers, irrigation is not a fixed variable but a part of daily management in the nursery. It is one of the most important and sensitive variables in the whole process of nursery cultivation, due to the small volume of the containers, the difficulty of rehydrating com monly used substrates and the influence of irrigation on plant nutrition and on the properties of the sub strate (Landis et al., 1989). There are two main factors to be considered with regard to this variable: the quan tity and the quality of the water. Both are influenced by the growth stage of the crop and must conform to the requirements of the plant at all times. Water quality can vary with the source, but irrigation with water of good quality is a requirement for high quality plant production (Will and Faust, 1999). The main water quality parameters are salinity, pH, hard ness and macroand micronutrient content. All of these parameters can affect plant growth either di rectly, by creating toxicity (such as that caused by Na+, Cl, B and heavy metals) and deficiencies, or in directly, by altering the availability of other plant nu Although they will depend on cultivation requirements, the properties of an ideal substrate may be summarised as: slightly acidic pH (5.56.5); high cation exchange capacity; low inherent fertility (which presupposes that the nursery uses fertilisation); proper balance of pore sizes (macropores and micropores) and a sterile envi ronment (freedom from pests and diseases) (Landis et al., 1990a). Aeration porosity (which depends on the macropores), is considered the most important prop erty of a cultivation substrate or growing medium (Bernier and González, 1995). trients. The most important factor in irrigation water is its alkalinity, which affects the pH of the substrate. Carbonates and bicarbonates cause an increase in the pH of the substrate over time due to their ability to neutralise H+ ions. The quantity of irrigation water depends on two dis tinct factors: watering frequency and the amount used at each watering. The two are closely intertwined and depend on the season (evaporationtranspiration) and the growing phase (Landis et al., 1989). Crucially for the growth and development of the plant, repeated ex posure of the substrate to intensive irrigation followed by no less intense desiccation significantly affects the availability of water and oxygen to the roots in the sub strate (Timmer and Miller, 1991; Miller and Timmer, 1994; Heiskanen, 1993). Irrigation needs may be es tablished by tactile and visual examination of the sub strate, TDR or gravimetry. The difficulty of managing this variable often leads nursery operators to irrigate too much, which results in a loss of efficiency (Karam and Nieman, 1994). 159 Nursery culture Substrate Fertilization The addition of nutrients to the plant, or fertilization, is one of the most important factors in the entire process of cultivation. This variable, along with irriga tion, makes it possible to manipulate the amount and quality of growth and accelerate or delay it, and may also alter the nutrient composition of the plant tissues, with effects on the level of reserves, rooting capacity and resistance to water stress, cold and disease. Nutrients are added by implementing a programme that sets out the following basic characteristics (Oliet, 1998): the type and composition of the fertilizer, the way in which it is applied (irrigation, incorporation into the substrate, etc.), the relative proportion of nutrients and the timing of fertilizer application (periodic, con stant or exponential) (Landis et al., 1989). In practice, the relative proportion of nutrients should be main tained by means of appropriate concentrations of the different minerals in solution in the medium, varying with the phase of plant growth (Ingestad, 1979; Lan dis et al., 1989; Van den Driessche, 1991). References Ansorena J (1994) Sustratos. Propiedades y caracterización. Editorial Mundi–Prensa, Madrid Bernier PY, González A (1995) Effects or physical properties of Sphagnum peat on the nursery growth of containerized Picea marianan and Picea glauca seedlings. Scandinavian Journal of Forest Research 10:176183 The application of slowrelease fertilizers is more ef ficient than fertirrigation, since the loss due to leach ing is smaller (Broschat, 1995) and there is less effect on salinity. However, in the early stages of cultiva tion, slowrelease fertilizer can produce a relatively high release of nutrients that are not taken up by the plant, with the opposite occurring towards the end of cultivation (Cabrera, 1997). On this basis, a com bination of controlledrelease fertilizers and fertirri gation is recommended by many authors (King, 1997; Eymar et al., 2000). The pH is regarded as the factor most involved in the availability of nutrients for plants, although in organic substrates with low fer tility an adequate supply of nutrients allows proper plant growth in a wide range of pH values (Whit comb, 1988). The availability of phosphorus may di minish with an alkaline pH in the presence of calcium and magnesium, since insoluble phosphates may form (Edwards, 1985). Fonteno WC (1993) Problems and considerations in deter mining physical properties of horticultural substrates. Acta Horticulturae 342:197204 Heiskanen J (1993) Variation in water retention characteris tics of peat growth media used in tree nurseries. Silva Fen nica 27:7797 Brissette JC, Barnett JP, Landis TD (1991) Container seedlings. In: Duryea ML, Dougherty PM (eds) Forest Regeneration Man ual. Kluwer Academic Publishers, The Netherlands Ingestad T (1979) Mineral nutrient requirement of Pinus sylvestris and Picea abies seedlings. Physiologia Plantarum 45:373380 Broschat TK (1995) Nitrate, phosphate and potassium leach ing from container grown plants fertilized by several meth ods. HortScience 30:7477 Karam NS, Niemiera AX (1994) Cyclic sprinkler irrigation and preirrigation substrate water content affect water and N leaching from containers. Journal of Enviromental Horticul ture 12:198202 Burés S (1997). Sustratos. Ediciones agrotécnicas SL, Madrid Cabrera RI (1997) Comparative evaluation of nitrogen release patterns from controlled release fertilizers by nitrogen leach ing analysis. HortScience 32:669673 Edwards IK (1985) How to maximize efficiency of fertilizers in a forest tree nursery. Proceedings of the Intermountain Nurserymens Association Meeting, Fort Collins Nursery culture 160 Eymar E, Cadahia C, Sánchez A, LópezVela A (2000) Com bined effect of slow release fertilizer and fertigation on nu trient use of Cupressus glabra grown in nursery conditions. Agrochimica, Vol XLIV 12:3948 Landis TD, Tinus RW, McDonald SE, Barnett JP (1989) The Con tainer Tree Nursery Manual. Vol 4 Seedling nutrition and irri gation. Agric. Handbk. 674. U.S.D.A, Forest Service, Washington (online URL http://www.rngr.net/Publications/ctnm) Landis TD, Tinus RW, McDonald SE, Barnett JP (1990a) The Container Tree Nursery Manual. Vol 2 Containers and growing media. Agric. Handbk. 674. U.S.D.A, Forest Service, Washing ton (online URL http://www.rngr.net/Publications/ctnm) Landis TD, Tinus RW, McDonald SE, Barnett JP (1990b) The Con tainer Tree Nursery Manual. Vol 5 Biological influences: nursery Landis TD, Tinus RW, McDonald SE, Barnett JP (1992) The Con tainer Tree Nursery Manual. Vol 3 Atmospheric environment. Agric. Handbk. 674. U.S.D.A, Forest Service, Washington (on line URL http://www.rngr.net/Publications/ctnm) Landis TD, Tinus RW, McDonald SE, Barnett JP (1994) The Con tainer Tree Nursery Manual. Vol 1 Nursery planning, development and management. Agric. Handbk. 674. U.S.D.A, Forest Service, Washington (online URL http://www.rngr.net/Publications/ctnm) Landis TD, Tinus RW, McDonald SE, Barnett JP (1990a) The Container Tree Nursery Manual. Vol 6 Containers and growing media. Agric. Handbk. 674. U.S.D.A, Forest Service, Washing ton (online URL http://www.rngr.net/Publications/ctnm) Miller BD, Timmer VR (1994) Steady – state nutrition of Pinus resinosa seedlings: response to nutrient loading, irrigation and hardening regimes. Tree Physiology 14:13271338 Oliet J (1998) La fertilización en el cultivo de los brinzales fo restales. In: Curso superior de viveros y producción de planta forestal autóctona para colonización de ecosistemas medite rráneos. Ministerio Medio Ambiente Fondo Social Europeo, ValsaínEl Serranillo Peñuelas JL, Ocaña L (1996) Cultivo de plantas forestales en contenedor. Principios y fundamentos. Ministerio de Agricul tura Pesca y Alimentación. Editoral MundiPrensa, Madrid Rey F (1997) Current trends in nutrition of container stock. In: Forest seedling nutrition from the nursery to the field. Symposium Proceedings. Haase DL, Rose R (eds). NTC. Oregon State University, Corvallis Svenson SE (2000) Comparing shade cloth and poly film for shading nursery crops. Nursery Management and Production 16:3942, 44 Timmer VR, Miller BD (1991) Effects of contrasting fertilization and moisture regimes on biomass, nutrients and water relations of container grown red pine seedlings. New Forests 5:335348 van den Driessche R (1991) Effects of nutrients on stock per formance in the forest. In: van den Driessche R (ed). Mineral nutrition in conifer seedlings. CRC Press Whitcomb CE (1988) Plant production in containers. Lacebark Inc, Stillwater Will E, Faust JE (1999) Irrigation water quality for greenhouse production. PB 1617 Agricultural Extension Service. Univer sity of Tennessee, Knoxville (online URL http://www.utexten sion.utk.edu/publications/pbfiles/pb1617.pdf) 161 Nursery culture pests and mycorrhizae. Agric. Handbk. 674. U.S.D.A, Forest Service, Washington (online URL http://www.rngr.net/Publications/ctnm) Cutting propagation Vegetative propagation by cuttings Vegetative propagation, as a production method for plants that are intended to be used for restoring natu ral areas, should be considered with precaution because of the risk of reducing the genetic diversity of new pop ulations. Nevertheless, in certain taxa with seeds that are delicate to manage, such as Salicaceae, or when the production of viable seeds is low, as frequently hap pens with Ulmus minor; or simply because for certain taxa this is the cheapest way of producing plants, veg etative propagation may be a useful alternative. Cutting propagation is a method commonly used for mass producing plants of many riparian species, taking advantage of their suitability for this type of propaga tion owing to the fact that they require high moisture content soils and are adapted to periodic flooding. In any event, if this method is used, special attention Types of cutting In highly simplified terms, three types of aerial cuttings can be differentiated: softwood cuttings: in woody plants, cuttings obtained from branches or flexible apexes that have still not lignified (normally in the months of May and June, or July). In general, cuttings of this type root rapidly, but it is important not to let them dry out. semihardwood cuttings: partially lignified, rigid cut tings obtained from the current year’s growth in hardwood plants during the period of vegetative ac tivity (in general, from midJuly to the beginning of the autumn). hardwood cuttings: lignified cuttings obtained from the previous year’s growth in hardwood plants dur ing the rest period (end of autumn, winter or the be ginning of spring). There are three types of hardwood cutting: straight cuttings, mallet cuttings and heel cuttings. The latter two are used for propagating species that root with difficulty. Mallet cuttings re should be paid to dioic species and to producing mate rial of both sexes in order to maintain the balance of male and female individuals. The determining factor in propagation by cuttings is correct adventitious root formation. This is a complex process in which a number of factors come into play. The success of the rooting process and the survival of the new plants depend on the combination of those factors. The aptitude of the species, the genetic fac tors of the individual, the physiological conditions of the parent plant, the type of cutting and its position on the plant, the time when the material is obtained, the treatments it undergoes and rooting conditions are the main factors to take into account (Hartmann and Kester 1987; Mac Cárthaig and Spethmann 2000). tain, at their base, a segment of the branch into which they are inserted, whereas the heel cutting only retains at its base a small portion of that branch, in the form of a heel, as its name indicates. Mention should be made of the ease with which some species can be multiplied using root segments. This type of material can be used in species that resprout from the root naturally, such as Populus tremula or Ulmus minor. However, the drawback to this propaga tion approach is that root segments are harder to ob tain than aerial cuttings, added to which it is not possible to extract a large quantity of material from the same individual. Some species can be propagated using more than one type of cutting, although this might pose the need for appropriate facilities, as cuttings taken in spring or summer are more delicate and require an environment with controlled humidity and temperature conditions. Cutting propagation 162 Material gathered from parent plants in a juvenile state usually forms roots more easily than material taken from adult plants. In turn, in adult individuals, cuttings taken from lower branches take root more easily than those taken from upper branches (Mac Cárthaig and Speth mann, 2000). This difference in behaviour is due to the phenomenon known as cyclophysis, which is the loss of juvenile potential – such as the capacity to form adven titious roots – which tissues suffer as their cells undergo a greater number of divisions. The lower branches in a tree come from tissues with a younger physiological age, despite the fact that they are chronologically older than the upper branches. It should be borne in mind, more Preparation of the cuttings over, that this variable behaviour according to the posi tion and hierarchy of the branches at the top persists for a time in the material gathered from them, a phenome non known as topophysis. As a result, in order to ensure successful cutting prop agation, parent plants in which tissues with an adult physiological age predominate should undergo rejuve nating treatments. The most common way to achieve rejuvenation is by severe pruning, although there are other alternatives, such as serial cutting propagation or etiolation, among others (Davis and Hartmann, 1988; Howard et al., 1988). Cuttings should be taken from healthy, vigorous plants, as far as possible avoiding or eliminating any buds or flowers on the stems or shoots that are gathered. The material that has been collected should be kept per manently in a cool, moist atmosphere, particularly in the case of softwood or semihardwood cuttings, which are highly susceptible to drying out. If the shoots are not processed immediately, they should be wrapped in plastic bags and kept at a low temperature (14 ºC). transmitting diseases. Making a bevel cut at the base of the cutting is recommended, as it helps to enlarge the surface area of bare tissue with the potential to send out roots and makes it easier to insert the cutting into the substrate. It is advisable to make a straight cut in the upper part of material removed from the middle and basal part of shoots, i.e. material that does not have an apical bud, to ensure that the correct orienta tion is maintained when the cutting is planted. Pruning shears or sharp knives should be used to take the cuttings, to produce clean cuts. The tools should be sterilised fairly frequently by submerging them in al cohol or a mixture of bleach and water (1:9) to avoid In cuttings with leaves, those in the middle or basal third are eliminated to avoid excess water loss from transpiration; likewise, half of the remaining leaves are cut if they are very big. Treatment with hormones Hormones are applied for the purpose of promoting or speeding up the production of roots or improving their quality. The hormone most often used is indolebutyric acid, in powder or in solution. When the powder form is used, the cuttings should be lightly shaken to elimi nate surplus hormone. When the liquid form is used, the immersion time for the cuttings will depend on the concentration of the solution. The hormone preparation that is used should be free from residues, so it is advisable to prepare the solutions just before using them and always dispose of any so lution that is left over once the cuttings have been treated. 163 Cutting propagation Topophysis and cyclophysis Rooting conditions The most appropriate conditions for stimulating root formation vary according to the type of cutting. Semi hardwood and softwood cuttings are kept at high rel ative humidity in a tunnel with mist, with bed heating at a temperature of approximately 20 ºC, using a sub strate that allows good aeration of the roots, such as a mixture of peat and perlite in a 1:1 proportion (Hart mann and Kester, 1987). Hardwood cuttings, in most cases, are planted directly into the growing substrate in a container. However, the most difficulttoroot species also require bed heating. Acclimatisation One of the most delicate processes in vegetative prop agation using cuttings is the acclimatisation stage. Once the material has taken root, it should gradually be introduced to more demanding temperature and hu References Davis FT, Hartmann HT (1988) The physiological basis of ad ventitious root formation. Acta Horticulturae 227:113120 Hartmann HT, Kester DE (1987) Propagación de plantas. Com pañía Editorial Continental, SA de CV, México DF The substrate should always be sterile, with good aer ation and low fertility. The cuttings are buried up to a third or half of their length. They should be watered at regular intervals, keeping the substrate permanently moist but avoiding saturation and direct sunlight. The planting method for root segment cuttings varies according to the species; some are buried horizontally in the medium and others are treated as if they were aerial cuttings. midity conditions. If the cuttings have been planted in trays or boxes or in small cell pots, the plants should be transplanted into containers of a suitable size to enable them to develop well. Howard BH, HarrisonMurray RS, Vasek J, Jones OP (1988) Techniques to enhance rooting potential before cutting co llection. Acta Horticulturae 227:176186 Mac Cárthaigh D, Spethmann W (eds) (2000) Krüssmanns Ge hölzvermehrung. Parey Buchverlag, Berlin Cutting propagation 164 Stool beds Planning and management of nursery stoolbeds Nursery stoolbeds are plantations for producing cut tings to be used for vegetative propagation of clones. These cuttings are taken from stool shoots, known as sets. some other existing production models are different, mainly with regard to the type of machinery and equip ment used for cultivation operations, the principles de scribed here are applicable to all of them. The present model may also be applied to the production of mate rials from other species, such as the genus Tamarix, in which reproduction through vegetative propagation is employed. This section describes the basic principles for setting up and operating a nursery stoolbed model to produce reproductive materials from Populus clones. Although Planning A stool duration of 2 to 4 years is recommended. Yearly renewal of all stools is more onerous and offers no added advantages. On the other hand, stump removal becomes more difficult and costly with increasing stool age. Stoolbeds require the same ground conditions as other forestplant production nurseries. Stoolbed size will depend on expected levels of pro duction, which in turn depend on the species or clone that is used and on the growing conditions that apply. In order to avoid soil exhaustion and allow for aera tion, as well as for the physical recovery of soil ele ments, it is advisable to leave areas fallow for a year. Following the first cut back, all the viable buds on a stool sprout the following spring, when a varying num ber of sets may be taken. At the end of the cycle, those that meet the cutting criteria – in terms of size (length and diameter), straightness, adequate lignification, the presence of welldefined buds and absence of damage – are selected. Production must be adequate to provide the required amounts of cuttings for plants and stool renewal. To this end, the first stage is to determine the necessary quantity of stools, planting distance and stool duration (that is, how many years the stools are to remain in production). Allowance must be made for a percentage of failures when planting cuttings for stools; in the case of poplars, less than 5% of the plants fail to root if conditions are appropriate. Stool planting distances vary according to the man agement methods and machinery. In general, stools are set out very close, in rows with paths between them for the passage of machinery and equipment. An estimate of the annual production in number of poplar sets and cuttings by age of stools is shown in Table 1. Table 2 gives an estimate of the surface areas and number of stools needed for a given output, with several examples of stool duration. Firstyear sets are cut level with the ground, or about 1 cm above it, to allow for adequate resprouting the following year. Table 1 Number of poplar sets and cuttings produced by age of stool Number of sets Number of cuttings 1 year old 1 3 2 years old 2 8 3 years old 3 12 4 years old 3 12 165 Stool beds Age of the stool Table 2 Amount of stools and surface area required to produce 1,000 poplar clone cuttings, based on nursery stoolbed rotation interval (plant ing distance: 2 m x 0.125 m) Stoolbed rotation interval Annual number Annual number Total cuttings of stools for of stools for to plant production of stool allowing for cuttings replacement 5% failure rate 1 year 2 years 3 years 4 years 333 91 43 29 111 8 2 1 467 104 48 32 Cultivation stages Site preparation Soil preparation begins with deep groundworking, in cluding one or two passes with the subsoiler, depend ing on ground conditions. If two passes are needed, the second pass should cross the first. This helps to aerate the soil, making it easier for water to reach the roots and allowing adequate drainage. Subsoiling is done in September or October, provided the weather conditions make it possible. The second task to be undertaken at the same time of year is harrowing. This should be done immediately after subsoiling, using one pass or two crisscrossing passes to grind down all the plant debris remaining on the land. The next step is organic composting. The compost is spread and ploughed in to a depth of 30 to 40 cm, making sure that the time between spreading the com post and burying it is as short as possible to avoid dry ing out and evaporation. At the end of the winter, when temperature and soil moisture conditions are appropriate, shallow harrowing is carried out to break up clods and lumps of soil and provide a finer finish and a good soil structure. In April, before setting out the cuttings, chemical com post is added. The soil is then harrowed immediately and left ready for planting. Taking cuttings Once the sets have been purchased or produced, the cuttings are made by selecting a bud (which becomes the terminal one) and cutting right above it; the basal end is then cut at the predetermined length. Cuttings should be at least 20 cm in length, with a straight Final number Surface area Total stool Total surface of stools by stool bed surface area (stool in stoolbed age(m2) area (m2) bed + fallow) (m2) 444 116.75 135 12.00 198 120 26.00 8.00 116.75 52.00 36.00 32.00 233.50 78.00 48.00 40.00 upper cut and a chamfered lower cut. In poplars, such a length ensures that each cutting has 3 or 4 viable, well developed buds. The upper cut is made 5 to 10 mm from the new terminal bud in order to make sure that it does not get buried when planted, since that would hinder sprouting and future stem growth, but in such a way that the bud is not affected by an excessively short cut. The cuttings should be about 10 to 20 mm in diameter and the material should be checked for proper lignification to ensure adequate reserves for subse quent plant growth. Rejects are discarded and the selected cuttings are tied into equal bundles. They are then put into cold storage at a temperature of 2 to 4ºC, making sure that the air circu lation is good and the minimum relative humidity is 85 %. The cuttings will be kept in storage until the time comes to set them out, when soil conditions are optimum. Cuttings may be colourcoded to identify different species and clones. Planting cuttings The cuttings are taken out of cold storage and soaked in clean water for 24 to 48 hours to ensure rehydration. They are then taken out of the water and planted. When planting, special care should be taken to leave at least one bud exposed. Mechanised planting proce dures often bury the cuttings completely, so only one shoot is obtained for each cutting planted. The problem of leaving only one bud exposed is that it may get dam aged by frost. When several viable buds are left on the cutting, it is advisable to select the strongest shoot and remove the rest so that the sets obtained are of uni form size and suitable for cutting production. Stool beds 166 Cultural treatments Control of competing vegetation Preemergence herbicides should be applied both at the time of planting cuttings and after the first cut back. After setting up the nursery stoolbed, weeding is not necessary when fallen leaves remain on the ground for long periods of time, as they prevent competing vegetation from growing. Stoolbed weeding also depends on the weather, which can cause different degrees of weed proliferation. If herbicides have been applied, paths are normally ma chineweeded once or twice during the vegetative pe riod and planted areas are weeded once by hand. Harrowing During the first year, paths are harrowed to facilitate aeration and irrigation or rainwater penetration. Sub sequent harrowing operations will be performed throughout the vegetative cycle, depending on the amount of grass on the paths and how much the soil has been compressed by watering. In established stoolbeds, the initial tillage should go deeper to break down the soil that has hardened since the previous year. Definitive groundworking is performed at this point, since machines will no longer be able to ac cess pathways when the plants have grown in size. Ridging When floodirrigation is to be used the land is divided Activities up by making ridges, to make it easier to control the watering operations. If spray or drip irrigation systems are used, no ridging is necessary. Chemical composting After soil preparation, chemical composting varies de pending on soil characteristics. It is important to re member that excessive fertiliser use will produce sets that are too thick and thus unsuitable for taking cut tings. It will also cause more sprouting and reduce the number of dormant buds. Watering Watering periods usually last for 5 to 7 months in Mediterranean climates, but will always depend on the weather and on soil characteristics. Although water needs vary, initial watering usually takes place every 15 days. The interval can then grad ually be increased, since evapotranspiration decreases as the stoolstems close the gaps between stools and the pathways. Treatment of pests and diseases Stools should be monitored at all times to avoid the appearance and proliferation of pests and diseases. All preventive and curative treatment procedures must be applied. Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Soil preparation Subsoiling and harrowing Organic composting and ploughing Harrowing Chemical composting and harrowing Taking material Cutting sets and cuttings Treatments Applying herbicide Harrowing Ridging Weeding Watering Plant health treatments Planting 167 Stool beds Figure 5 Sequence and duration of activities for the management of a poplar nursery stoolbed (operations can be brought forward or moved back in time depending on the vegetative period, which varies from year to year and from one place to another) Harvesting Once the vegetative cycle is over, once the stools have shed their leaves, the amount of available sets is counted. Sets that are good for highquality cuttings are selected visually on the basis of size, straightness, ade quate lignification and bud viability. After counting the sets, the number of cuttings produced can be estimated. When the material is to be used at the nursery itself, the sets are cut and the cuttings are prepared as de scribed in the section on nursery stoolbeds. When the material is intended for production elsewhere, it can be stored in the form of sets or cuttings. Sets are cut, tied in equal bundles and stored in shaded, soilcov ered ditches until ready for dispatch. In the case of poplars, the materials produced must comply with Eu ropean standards (Tables 3 and 4). Sets that are not selected for cuttings are taken from their stools and discarded. The stools are then ready to sprout new shoots in the next vegetative period. Clear ing all debris from the bed concludes the work until the next cycle. Table 3 External quality standards for cuttings and sets of Populus spp. as required by Directive 1999/105/EC Type of material Cuttings Maximum age of the wood Sets 2 Minimum number of well formed buds 3 2 Free from necroses or damage by harmful organisms Free from signs of desiccation, overheating, mould or decay Free from injuries other than pruning cuts 5 √ √ √ √ √ Only a single stem √ No excessive stem curvature √ Table 4 Dimensions for cuttings and sets of Populus spp. as required by Directive 1999/105/EC Type of material Class Cuttings Sets Minimum length top (cuttings) / midlength (sets) (mm) 0.20 10 3.00 15 EC1 0.20 Non Mediterranean N1 1.50 Mediterranean 3.00 EC2 regions N2 regions S2 S1 Minimum diameter at (m) 4.00 8 6 25 30 Stool beds 168 Master certificate European regulations governing the marketing of forest reproductive material Reproductive materials used in forestation projects must be adapted to the conditions of the area into which they are to be introduced. If production is envis aged, the materials must have undergone selection, and in some cases improvement, for traits of interest. In connection with this, the European Union has issued a set of standards for the marketing of forest reproductive materials belonging to the species most commonly em ployed for reforestation in Europe. These rules are de scribed in Directive 1999/105/EC and related decisions and compliance by member states is compulsory. These standards are designed to promote transparency in the market for reproductive forestry materials by guaranteeing their quality, in terms of physical condi tions, whatever genetic selection and improvement the plants may have undergone and, in some instances, their geographical origins. To this end, the directive in troduces a system for the approval of basic materials from which seeds or parts of plants may be collected for subsequent plant production, and certificates and control mechanisms to ensure traceability throughout the collection, production and marketing process up to delivery to the final user. The sphere of application of these rules comprises re productive materials, intended for forestry purposes, of a series of species. They include typical riverine vege tation taxa such as Alnus glutinosa, Alnus incana, Frax inus angustifolia, Populus spp., Tilia cordata and Tilia platyphyllos and species that could be used in foresta tions in this type of habitat, such as some Quercus, Juglans spp or Robina pseudoacacia, among others. Each member state may also add further taxons for in ternal marketing purposes. For instance, Spain has in cluded other species, some of which are riparian (Ulmus glabra, Ulmus minor or Tamarix gallica). When the material is to be used in riparian restoration projects and is of no interest for propagation, the seeds are collected from basic materials which may be taken from seed sources or, possibly, stands; that is to say, sourceidentified or selected seeds respectively (Table 5). If the material follows vegetative propaga tion patterns, the Council Directive limits its produc tion to the selected (masspropagated from plants obtained from seeds), qualified or tested categories (Table 6). In the case of certain species of no market ing interest that traditionally propagate through parts of plants, such as some native poplars, it is impossi ble to comply with the requirements established for these categories, which are aimed at genetically im proved material. This difficulty may be solved by con sidering the sustainable use of such types of nonimproved materials as adapt naturally to local or regional conditions. In accordance with article 4.4 of Directive 1999/105/EC, such sustainable use could be based on promoting in situ conservation by avoiding nonautochthonous materials that might introgress into local populations. For nonregulated species, it would also be advisable to apply some of the criteria envisaged under these rules, especially as regards source control and traceability though to planting out. In any event, together with these rules and regula tions governing basic protocols it would be highly ad visable to consider a set of best practices for the production of materials, such as collection from pop ulations of a certain size and from different individ uals more or less distant from each other, or the promotion of clonal mixtures in the case of vegetative propagation, as a means to guarantee a certain de gree of genetic variation. Table 5 Category under which reproductive material from the different types of basic material may be marketed Category of forest reproductive material ■ ■ ■ ■ sourceidentified selected qualified tested Seed source √ Stand Seed orchard Parents of family Clone Clonal mixture √ √ √ √ √ √ √ √ √ √ √ 169 Master certificate Type of basic material Table 6 Category under which different types of reproductive material may be marketed Type of reproductive material Listed species (except artificial hybrids and GMO) Category ■ ■ ■ Artificial hybrids ■ ■ ■ Genetically modified organisms ■ ■ sourceidentified Fruits and seeds Parts of plants Plants selected √ qualified √ √* √ √ tested √ √ √ selected √ √ √ qualified √ √ √ tested √ √ √ tested √ √ √ √ √ √ * mass propagated from seeds Master certificate 170 Plant passport European Union regulations regarding phytosanitary cer tificates and plant passports include a series of direc tives that aim to avoid the introduction into member states and the propagation inside the Community of or ganisms that are harmful to plants or plant products. The basic plant health passport rules are described in two directives: Council Directive 2000/29/EC of 8 May 2000 on pro tective measures against the introduction into the Community of organisms harmful to plants or plant products and against their spread within the Com munity; Commission Directive 92/90/EEC of 3 November 1992 establishing obligations to which producers and im porters of plants, plant products or other objects are subject and establishing details for their registration. These regulations are based on the compilation of an inventory of harmful organisms that are considered es pecially hazardous and whose introduction into the Community must be forbidden. The inventory also in cludes harmful organisms whose introduction through the medium of certain plants must also be forbidden. Since the detection of some of these organisms is not simple, the introduction into the European Union of plants or plant products from certain countries is for bidden in some cases, or certified proof of the applica tion of special controls in the producing country is demanded. These controls are not only applicable to plants and plant products from outside the Community: internal production is also subject to inspection. In this case, the plant passport is the document that certifies that the plants have undergone the required official checks and are free from the harmful organisms described in the above regulations. The passport does not guarantee that they are free from diseases and pests, only that none of the diseases and pests listed in the regulations has been found in the plant health inspection of the plant materials. Plant passports, whose contents are standardised, are issued by the responsible official bodies of member states. With a view to protecting crops or natural populations that are especially sensitive or whose production or ecological value is considered a priority, the European regulations state that special protection must be given to certain geographical areas. A protected zone may be a region, a country or a group of countries of the Eu ropean Union in which one or several harmful organisms which are found in other EU countries are not endemic or do not usually occur. The checks appli cable to plant materials intended for a given protected zone are specific to that destination and are listed under the requirements for a special plant passport known as the ‘ZP passport’. Inspections that do not refer to these specific requirements are not valid for the rel evant protected area. This passport must bear the let ters ‘ZP’ followed by the code of the country or region of destination of the plant materials to prove that plant health inspection has been carried out for that destination. Plant passport regulations are very detailed and subject to constant updating. Frequent reference to legislation databases is therefore advisable to check for possible changes. The EuroLex web page (http://europa.eu.int/eurlex/lex/RECH_menu.do) pro vides all recent updates. As regards the production of plants for riverine restoration projects, the species in this handbook that would be affected by these regulations are: Arbutus unedo, Humulus lupulus, Laurus nobilis, Platanus ori entalis, Populus spp., Prunus mahaleb, Prunus spinosa, Rubus ulmifolius, Viburnum tinus and Vitis vinifera. Plants and other plant products of the above species must be accompanied by a plant passport when circu lating within the Community. For plants and part of plants of Populus spp. to enter into or circulate within protected areas, the ‘ZP’ passport is required. Regarding the entry of products from outside the Com munity, the regulations should be consulted in each in dividual case to check for any restrictions. Depending on the country of origin, the introduction of certain products into the European Union may be forbidden. 171 Plant passport European plant health regulations Populus spp. Diagnostic traits for Populus alba, P. tremula and P. x canescens Taxon Rhytidome Winter buds Leaves Petioles Catkins Male flowers P. alba L. ■ ■ ■ not viscid initially white tomentose, later reddish glabrescent short shoots: suborbicu lar, subelliptic or subpentagonal, entire or sinuatedentate ■ long shoots: palmately lobed, deltoid or ovate oblong; base generally cordate ■ initially whitetomen tose; later dark green, glabrous above, white or greengreyish, tomentose beneath ■ short shoots: 23 cm; long shoots: up to 17 cm ■ not much flattened ■ ■ ■ ■ ■ Stigmas white or greyish ■ ■ female: up to 12 cm long scales in female catkins crenate or subentire, hairy; scales in male catkins: irregularly crenatedentate or subentire, hairy (3)8(10) stamens anthers purple at first, later yellow greenyellowish bipartite P. tremula L. ■ ■ ■ light greygreenish short shoots: ovate orbicular, obtuse, base truncate or cordate, irre gularly dentatecrenate ■ long shoots: larger, ovatetriangular, apex acute, base truncate or cordate ■ initially more or less hairy; later both sides green, quite discolorous, glabrous ■ ■ ■ ■ ■ ■ ■ ■ ■ whitish frequently slightly viscid initially rather pubes cent, later brownish glabrescent or glabrous ■ ■ P. x canescens (Aiton) Sm. ■ ■ ■ short shoots: veins prominent, glandulose (2,5)46(8) cm strongly flattened laterally 512 cm long scales hairy, palmatelaciniate (4)8(12) stamens anthers purple purple bifid ■ ■ ■ ■ ■ short shoots: oval or suborbi cular, sinuatedentate long shoots: deltoidovate to cordate short shoots: initially greyish pubescent; later more or less concolorous, glabrous or glabrescent; long shoots: greytomentose beneath short shoots: more than 5 cm strongly flattened laterally female: 46 cm long scales in female catkins irregularly laciniate 815 stamens Populus 172 Diagnostic traits for Populus nigra, P. deltoides and P. x canadensis Trunk Twigs Leaves Female catkins Male flowers Capsules P. nigra L ■ ■ soon blackish, furrowed often with large bosses with epicormic shoots terete or slightly angled at apex ■ first yellowish, later greyish ■ long shoots: 510 x 48 cm; short shoots: smaller and broader ■ short shoots: rhombic, base broadly cuneate or more or less rounded; long shoots: trullate ■ margin not ciliate ■ without glands at base ■ ■ ■ ■ 715 cm long 625 stamens 2 valves P. deltoides Marshall ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ without bosses strongly angled P. x canadensis Moench. ■ ■ without bosses usually slightly angled at apex first greenish, later greenishbrown to greyishbrown 1018 cm, longer than wider ovatecordate or deltoid, base usually truncate margin densely ciliate glands at base ■ ■ ■ deltoid or ovate margin shortly ciliate usually glands at base 1520 cm long 3060 stamens ■ 1525 stamens 34 valves 173 Populus Taxon Salix spp. Distribution Salix alba L. General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Caucasus, Western and Middle Asia, Siberia, China, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, Bosnia Herzegovina, Montenegro, Albania, Greece, Cyprus, Tur key, Syria, Lebanon, Israel, Tunisia, Algeria, Morocco Salix amplexicaulis Bory General distribution: Southwestern Europe, Northern Africa Mediterranean region: Italy, Montenegro, Albania, Greece, Turkey Salix atrocinerea Brot. General distribution: Southwestern, Middle and North ern Europe, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corsica), Italy (Sardegna), Tunisia, Algeria, Morocco Salix 174 Distribution Salix eleagnos Scop. General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Western Asia, Northern Africa Mediterranean region: Spain, France (incl. Corse), Italy, Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Morocco Salix fragilis L. General distribution: Southwestern, Southeastern, Middle and Eastern Europe, Caucasus, Western Asia Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, Bosnia Herzegovina, Montenegro, Albania, Greece, Turkey Salix pedicellata Desf. General distribution: Southwestern and Southeastern Europe, Northern África 175 Salix Mediterranean region: Spain, France (Corse), Italy (Sardegna and Sicilia), Tunisia, Algeria, Morocco Distribution Salix purpurea L. General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern Asia, Mongolia, Northern Africa Mediterranean region: Portugal, Spain, France (incl. Corse), Italy (incl. Sardegna and Sicilia), Croatia, Bo sniaHerzegovina, Montenegro, Albania, Greece, Tur key, Syria, Lebanon, Tunisia, Algeria, Morocco Salix salviifolia Brot. General distribution: Southwestern Europe Mediterranean region: Portugal, Spain Salix triandra L. General distribution: Southwestern, Southeastern, Middle, Northern and Eastern Europe, Caucasus, West ern, Middle and Eastern Asia, Siberia, Russian Far East, Mongolia, China, Northern Africa Mediterranean region: Portugal, Spain, France, Italy, Croatia, BosniaHerzegovina, Montenegro, Albania, Greece, Turkey, Israel, Tunisia, Algeria Salix 176 7 mm 1 cm Salix alba L. 177 Salix 5 mm 5 mm 3 mm 1 cm Salix amplexicaulis Bory Salix 178 5 mm 1 cm 1 cm 179 Salix Salix atrocinerea Brot. 1 cm 1 cm 5 mm Salix eleagnos Scop. Salix 180 5 mm 1 cm 5 mm 181 Salix Salix fragilis L. 1 cm 1 cm 1 cm Salix pedicellata Desf. Salix 182 5 mm 5 mm 1 cm 183 Salix Salix purpurea L. 1 cm 5 mm 1 cm Salix salviifolia Brot. Salix 184 5 mm 1 cm 5 mm 185 Salix Salix triandra L. Salix 186 ▪ trunk: greyishbrown, deeply longitudinally furrowed ▪ 210 x 12 cm ▪ linear or linearlanceolate ▪ base cuneate ▪ margin revolute, finely glanduloseserrate ▪ glabrous above; densely tomentose beneath ▪ base cuneate ▪ margin serrate ▪ silky or glabrescent, rarely glabrous, glaucous ▪ glabrescent or glabrous, rarely pubescent ▪ terete, very fragile at junctions ▪ branches: glabrous, orange, greenish or reddishbrown ▪ trunk: greyish or greyishbrown, becoming fissured ▪ tree to 825 m S. fragilis L. ▪ alternate ▪ 210 x 0.52 cm ▪ lanceolate, oblonglanceolate, obovatelanceolate, oblongobovate or linearlanceolate ▪ glabrous ▪ angled ▪ glabrous ▪ smooth, reddishbrown, sometimes almost black, greenish or brown, flaking off in irregular patches ▪ shrub to 46(10) m S. triandra L. …/… ▪ base rounded, rarely cuneate or quite attenuate ▪ margin glanduloseserrate, ▪ margin not revolute, sometimes subserrate glanduloseserrate ▪ glabrous, shiny above; ▪ glabrous, rarely quite hairy beneath glaucescent or pale green beneath ▪ 516 x 13 cm ▪ lanceolate to ovatelanceolate ▪ glabrescent, slightly pubescent ▪ initially glabrescent, then at base and/or apex glabrous, shiny ▪ alternate ▪ alternate ▪ pubescent or glabrescent, orange or yellow ▪ glabrous, reddishbrown ▪ shrub up to 6 m, rarely tree S. eleagnos Scop. ▪ up to 10 x 12.5 cm ▪ lanceolate ▪ alternate ▪ silky Buds Leaves ▪ silky Twigs ▪ branches: smooth, brown, reddishbrown or orangeyellow ▪ tree up to 25 m Bark Habit S. alba L. Taxon Leaves linear, lanceolate or ovatelanceolate Diagnostic traits for species of Salix L. distributed in the Mediterranean region 187 Salix 27 x 1 cm peduncle long loose appearing at the same time as leaves ▪ ▪ ▪ ▪ filaments free filaments hairy 2 stamens 2 nectaries ▪ outer side glabrescent; inner side pubescent ▪ caducous ▪ apex acute ▪ uniformly yellowish ▪ margin entire or serrate ▪ ▪ ▪ ▪ ▪ 25(7) mm ▪ pubescent ▪ margin dentade ▪ caducous ▪ linearlanceolate S. alba L. Female flowers ▪ pistil glabrous, sessile or shortly stipitate ▪ style short ▪ stigmas bifid ▪ 1 nectary Male flowers Floral bracts Catkin bracts Catkins Petioles Stipules Taxon …/… filaments free filaments hairy 3 stamens 2 nectaries ▪ persistent ▪ ▪ ▪ ▪ ▪ style medium ▪ stigmas bifid ▪ 2 nectaries ▪ style short ▪ stigmas bifid ▪ 1 nectary filaments free filaments hairy at base 2 stamens 2 nectaries ▪ style long ▪ stigmas bifid ▪ 1 nectary ▪ ▪ ▪ ▪ ▪ appearing at the same time as leaves ▪ (2)3.5(7) x 1 cm ▪ pistil glabrous, stipitate filaments united at lower third filaments hairy 2 stamens 1 nectary ▪ 510 mm ▪ glabrous or glabrescent, sometimes glandulose at the junction of leaf blade ▪ pistil glabrous, shortly stipitate ▪ pistil glabrous, stipitate ▪ ▪ ▪ ▪ ▪ uniformly pale yellow, brownish ▪ uniformly coloured when adult, sometimes apex red ▪ apex obtuse, rarely emarginate ▪ margin hairy ▪ margin hairy ▪ outer side hairy; inner side glabrescent ▪ persistent ▪ caducous ▪ margin entire ▪ > 5 mm ▪ glabrescent or glabrous ▪ semireniform, large S. triandra L. ▪ caducous; present in young shoots ▪ persistent ▪ semicordate, very asymmetric, broad S. fragilis L. ▪ 27 x 0.51 cm ▪ peduncle long ▪ dense ▪ appearing just before the leaves ▪ appearing at the same time or at the same time as leaves ▪ up to 3 x 1 cm ▪ sessile or peduncle very short ▪ < 5 mm ▪ hairy ▪ absent or reduced to glands S. eleagnos Scop. Salix 188 ▪ pubescent ▪ alternate ▪ 210 x 12 cm ▪ 510 x 13 cm ▪ 210 x 12 cm ▪ oblongobovate, elliptic, ▪ elliptic, oblongelliptic, ▪ oblongobovate, oblong obovateelliptic, lanceolate lanceolate or obovate lanceolate, obovate or obovatelanceolate lanceolate lanceolate or linea lanceolate ▪ base rounded, cuneate ▪ base rounded or shortly ▪ base rounded or or shortly attenuate attenuate, rarely cuneate shortly attenuate ▪ margin revolute, entire, ▪ margin revolute, entire, ▪ margin revolute, dentade paucidentate or paucidentate or serrate, sometimes dentateserrate dentateserrate paucidentate or entire ▪ glabrous or tomentose ▪ glabrescent above; ▪ tomentose or glabrescent above, reddish and white thinly pubescent or sometimes glabrous, hairs; tomentose beneath, glabrescent, glaucous above; densely reddish and white hairs, beneath tomentose beneath sometimes glabrous, glaucous ▪ veins prominent beneath ▪ veins prominent beneath ▪ pubescent ▪ alternate ▪ shrub up to 6 m S. purpurea L. …/… ▪ base rounded, sometimes shortly attenuate or cuneate ▪ margin not revolute, dentate towards apex, entire towards base ▪ glabrous above; glaucescent beneath ▪ base cordate semiamplexicaul ▪ margin serrate towards apex, entire towards base ▪ glabrous, dark green above; glabrous, glaucous beneath ▪ 57 x 11.5 cm ▪ linear, linearlanceolate, oblongobovate or spatulate ▪ glabrous ▪ opposite, sometimes alternate ▪ up to 3050 x 816 mm ▪ oblonglanceolate or oblong ▪ glabrous ▪ opposite or suboposite, rarely alternate ▪ glabrous, very shiny ▪ yellowishbrown to reddish ▪ glabrous, shiny greyish, brown or dark brown yellowish, reddishbrown or black ▪ decorticate wood smooth, unridge ▪ shrub to 3(5) m S. amplexicaulis Bory Leaves generally opposite ▪ pubescent or glabrescent ▪ glabrous Leaves Buds ▪ tomentose ▪ pubescent ▪ shrub up to 6 m Twigs ▪ shrub or small tree up to 10 m ▪ glabrous, reddishbrown ▪ glabrous, reddishbrown ▪ glabrous, reddishbrown or greyishbrown or greyishbrown or greyishbrown ▪ decorticate wood with ▪ decorticate wood with ▪ decorticate wood with numerous prominent numerous prominent numerous prominent ridges ridges ridges ▪ shrub, sometimes small tree up to 12 m S. salviifolia Brot. Bark Habit S. pedicellata Desf. S. atrocinerea Brot. Taxon Leaves broadly lanceolate, oblongelliptic, elliptic or obovate Diagnostic traits for species of Salix L. distributed in the Mediterranean region 189 Salix ▪ ± 5 mm ▪ hairy Petioles ▪ up to 7 x 12 cm ▪ up to 7 x 1(2) cm ▪ sessile or peduncle short ▪ peduncle short ▪ appearing before the ▪ appearing before the leaves leaves Female flowers Male flowers Floral bracts ▪ pistil glabrous, longstipitate ▪ style medium ▪ stigmas entire or bifid ▪ filament glabrous or glabrescent ▪ 2 stamens ▪ filaments more or less hairy at base ▪ 2 stamens ▪ 1 nectary ▪ pistil tomentose, stipitate ▪ style short ▪ stigmas entire or bifid ▪ 1 nectary ▪ 2 stamens ▪ 1 nectary ▪ filaments free ▪ filaments free ▪ filaments hairy near base ▪ filaments united ▪ apex darker ▪ usually opposite ▪ peduncle short ▪ (0.3)0.53.2 mm ▪ caducous ▪ small S. amplexicaulis Bory ▪ pistil pubescent, stipitate ▪ pistil pubescent, sessile or shortly stipitate ▪ style short ▪ generally stigmas entire ▪ 1 nectary ▪ filaments united at base or free ▪ filaments hairy ▪ hairy ▪ apex darker ▪ greyish, densely tomentose ▪ 37 x 12 cm ▪ peduncle short ▪ appearing at the same time as leaves ▪ < 5 mm ▪ tomentose ▪ persistent ▪ margin serrate ▪ tomentose ▪ semicordate S. salviifolia Brot. ▪ apex darker ▪ usually apex darker ▪ apex obtuse ▪ apex obtuse ▪ more or less densely hairy ▪ hairy Catkin bracts Catkins ▪ ≥ 5 mm ▪ hairy S. pedicellata Desf. ▪ semicordate or semireniform, broad ▪ margin not much dentade ▪ margin dentate ▪ glabrescent above; tomentose beneath ▪ caducous; present in ▪ caducous young shoots Stipules ▪ semicordate or reniform S. atrocinerea Brot. Taxon …/… ▪ style short, glabrous ▪ stigmas entire ▪ 1 nectary ▪ pistil pubescent, sessile ▪ 1 nectary ▪ filaments hairy ▪ filaments united ▪ usually apex darker ▪ apex obtuse ▪ hairy ▪ 3 x 1 cm ▪ sessile or peduncle short ▪ appearing before the leaves ▪ < 5 mm ▪ glabrous ▪ caducous S. purpurea L. Tamarix spp. Distribution Tamarix africana Poiret General distribution: Southwestern and Southeastern Europe, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia), Tunisia, Algeria, Morocco Tamarix boveana Bunge General distribution: Southwestern Europe, Northern Africa Mediterranean region: Spain, Libya, Tunisia, Algeria, Morocco Tamarix canariensis Willd. General distribution: Southwestern and Southeastern Europe, Northern Africa, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France, Italy (Sardegna and Sicilia), Libya, Tunisia, Al geria, Morocco Tamarix 190 Distribution Tamarix dalmatica Baum General distribution: Southeastern Europe Mediterranean region: Italy, Croatia, Bosnia Herze govina, Montenegro, Albania, Greece Tamarix gallica L. General distribution: Southwestern and Southeastern Europe, Macaronesia Mediterranean region: Portugal, Spain (incl. Baleares), France (incl. Corse), Italy (incl. Sardegna and Sicilia) Tamarix hampeana Boiss. & Heldr. General distribution: Southeastern Europe, Western Asia 191 Tamarix Mediterranean region: Greece, Turkey, Israel Distribution Tamarix parviflora DC. General distribution: Southeastern Europe, Western Asia, Northern Africa Mediterranean region: Croatia, BosniaHerzegovina, Montenegro, Albania, Greece (incl. Kriti), Turkey, Israel, Algeria Tamarix smyrnensis Bunge General distribution: Southeastern and Eastern Europe, Caucasus, Western and Middle Asia Mediterranean region: Greece (incl. Kriti), Cyprus, Turkey, Syria, Lebanon, Israel Tamarix tetranda Pallas ex Bieb. General distribution: Southeastern and Eastern Europe, Western Asia Mediterranean region: Albania, Greece, Cyprus, Turkey, Lebanon Tamarix 192 193 Tamarix ▪ 1.54 mm long ▪ smooth or minutely papillose ▪ margin scarious ▪ 26 mm long ▪ papillose ▪ reddishbrown or brownish T. boveana Bunge ▪ synlophic to parasynlophic ▪ muticous or slightly apiculate ▪ (2.7)34 x 1.32 mm ▪ narrowly ovate to unguiculate ▪ muticous or slightly apiculate Nectariferous ▪ synlophic disc ▪ 23.3 x 12 mm ▪ trullate to ovate Anthers Petals ▪ 11.8 mm long ▪ 1.73 x 1.52.4 mm ▪ trullate, acute; outer slightly ▪ outer trullate, acute; inner longer, narrower and more acute ovate, slightly shorter, obtuse ▪ margin subentire ▪ margin outer entire; inner denticulate at apex Sepals ▪ tetramerous, rarely tetramerous and pentamerous ▪ margin densely papillose ▪ equal or longer than calyx ▪ linear, acute ▪ pentamerous ▪ longer or shorter than calyx ▪ narrowly oblong, shortly acute, to triangular, acuminate ▪ margin usually papillose Flowers Bracts Inflorescences ▪ (15)3070(80) x (5)69 mm ▪ 40150 x 712 mmq ▪ usually on previous year's branches ▪ usually on previous year's branches ▪ rachis sometimes papillose ▪ usually simple ▪ usually simple ▪ black or darkpurple Leaves Bark T. africana Poiret Taxon ▪ glaucous ▪ green ▪ synlophic ▪ fleshy ▪ apiculate ▪ 1.21.6(1.7) x 0.51 mm ▪ obovate ▪ margin densely denticulate ▪ 0.61 mm long ▪ trullate, acute ▪ pentamerous ▪ equal or longer than calyx ▪ lineartriangular, long acuminate to subulate ▪ margin papillose ▪ synlophic ▪ not very fleshy ▪ slightly apiculate ▪ (1.6)1.72 x 0.81 mm ▪ elliptic to ovate ▪ 0.71.8 mm long ▪ trullate to ovate, acute; inner somewhat longer and more obtuse ▪ margin not very denticulate ▪ pentamerous ▪ margin denticulate ▪ usually shorter than calyx ▪ narrowly triangular, acuminate ▪ 1050 x 35 mm ▪ 1050 x 35 mm ▪ usually on current year's branches▪ usually on current year's branches ▪ rachis usually papillose ▪ rachis usually glabrous ▪ densely compound ▪ loosely compound ▪ 1.32.5 mm long ▪ few or without saltsecretory glands ▪ brownishblack or deep purple T. gallica L. ▪ 1.32.5 mm long ▪ many saltsecretory glands ▪ purple or reddishbrown T. canariensis Willd. Diagnostic traits for species of Tamarix L. distributed in the Western European Mediterranean region Tamarix 194 ▪ 24 mm long ▪ 2060(130) x (8)1012 mm ▪ usually on previous year's branches ▪ simple or loosely compound ▪ 1.754 mm long ▪ brown or reddishbrown T. hampeana Boiss. & Heldr. ▪ fleshy ▪ paralophic ▪ 2.54 mm long ▪ ovateelliptic T smyrnensis Bunge ▪ shorter than calyx ▪ longer than pedicels ▪ synlophic ▪ 1.82.5 mm long ▪ parabolic or oblong ▪ 22.5 mm long ▪ outer trullate, keeled, acute; inner ovate, shorter, obtuse ▪ tetramerous, occasionally ▪ oblong, herbaceous in proximal half, obtuse ▪ shorter than calyx ▪ longer than pedicels ▪ hololophic, lobes entire to ▪ paralophic to parasynlophic faintly emarginate, hypodiscal insertion of stamens ▪ usually fleshy ▪ fleshy ▪ 22.75mm long ▪ 2.23 mm long ▪ovate to suborbicular, strongly ▪ ovate to ovateelliptic keeled ▪ persistent ▪ margin irregularly denticulate ▪ margin entire ▪ 1 mm long ▪ trullate to ovate, obtuse ▪ pentamerous pentamerous ▪ margin almost entirely scarious ▪ tetramerous ▪ 35 mm long ▪ margin scarious ▪ black to greyishblack T. tetrandra Pallas ex Bieb. ▪ up to 40 x 4 mm ▪ 3060 x 67 mm ▪ usually on previous year's ▪ usually on previous and/or current year's branches year's branches ▪ loosely compound ▪ simple or loosely compound ▪ 23.5 mm long ▪ reddish brown to brown ▪ triangular acuminate, obtuse ▪ shorter than calyx ▪ longer than pedicels ▪ 1040 x 36 mm ▪ usually on previous year's branches ▪ simple ▪ 1.62.5 mm long ▪ reddishbrown to purple T. parviflora DC. ▪ 11.5 mm long ▪ joined at base; outer trullate, keeled, acute; inner ovate, obtuse ▪ margin outer subentire; inner ▪margin irregularly denticulate slightly denticulate ▪ 22.5 mm long ▪ trullate, acuminate; outer more acute ▪ muticous or slightly apiculate ▪ 2.34.5(5) x 1.41.8 mm ▪ narrowly ellipticobovate, unguiculate ▪ subpersistent ▪margin entire or scarcely denticulate ▪ 1.53.5 x 1.52.4 mm ▪ trullate, more or less keeled; outer more acute ▪ tetramerous, sometimes few ▪ tetrapentamerous pentamerous ▪ equal or longer than calyx ▪ shorter than calyx ▪ shorter than pedicels, sometimes equal to or longer ▪ broadly triangular, obtuse to acuminate ▪ margin scabridpapillose Nectariferous▪ paralophic disc Anthers Petals Sepals Flowers Bracts Inflorescences ▪ 2070 x 712 mm ▪ usually on previous year's branches ▪ simple ▪ reddishblack, brownishblack to black Leaves Bark T. dalmatica Baum Taxon Diagnostic traits for species of Tamarix L. distributed in the Eastern European Mediterranean region Glossary acuminate tapering gradually to a protracted point acute ending in a point adaptability the ability of an individual or a population to change to fit changed environmental conditions allotetraploid an organism having four sets of chromosomes, produced by the union of genetically distinct chromosome sets (usu ally form different species) alternate not opposite or whorled; placed singly at nodes amplexicaul clasping the stem androdioecy sex expression that occurs when both male and hermaph rodite individuals are present in a population andromonoecy sex expression that occurs when both male and hermaph rodite flowers occur on the same individual anemophilous pollinated by wind anther the terminal portion of a stamen, which bears the pollen sacs anthesis the period during which a flower is fully open and functional apex the distal part of a leaf apical bud a bud at the tip of a shoot apiculate ending in a mucro apomixis development of an embryo without the occurrence of fer tilisation. Since this process does not involve the forma tion of gametes or meiosis, the progeny are genetically identical to their parent attenuate tapering gradually autochthonous originating in the region where it is found autogamy selffertilisation auxin a class of hormones that promotes and regulates the growth and development of plants, including cell elongation axillary bud a bud at the junction of a stem and a petiole backcrossing a cross of an hybrid with one of the two parental indi viduals or species berry a fleshy, indehiscent, manyseeded fruit containing no hard parts except the seed bifid divided into two parts along less than half its length bipartite divided into two parts along at least half its total length bipinnate twice pinnate; a pinnate leaf, having also pinnately di vided segments bract a modified leaf, generally small, growing just below a flower or an inflorescence bracteole A small modified leaf on the flower stalk, above the bract and below the calyx caducous dropping off or shedding early calyx all the sepals of a flower cambium a layer of actively dividing cells responsible for the in crease in thickness of stems and roots capsule a dry dehiscent fruit that develops from two or more carpels carpel modified leaf forming a pistil cation an ion or group of ions having a positive charge cation exchange a chemical process in which cations of like charge are ex changed equally between a solid and a solution 195 Glossary achene a small, dry, indehiscent, usually singleseeded fruit catkin a long inflorescence, usually pendulous, with tiny, unisex ual, petalless flowers caudate bearing a taillike appendage centre of origin a geographical location or local region where a particular group of organisms is believed to have originated chromosome a structure in all living cells, consisting of a molecule of DNA bonded to various proteins, that carries the genes ciliate bearing hairs on the margin clone cells, groups of cells or organisms that are produced asex ually from a single ancestor, to which they are genetically identical compound inflorescence an inflorescence with more than one flower per branch compound leaf one having two or more distinct leaflets concolorous of uniform colour above and below connate united with a structure of the same kind cordate heartshaped coriaceous having a leathery texture corolla the petals of a flower considered as a group, often coloured corymb an inflorescence whose outer flowers have longer pedicels than the inner ones, so that together they form a round, rather flattopped cluster; the outer flowers open before the inner ones corymbiform a round, rather flattopped inflorescence, resembling a corymb crenate with rounded teeth crossbreeding breeding from individuals of different species, varieties or breeds crossfertilisation fertilisation by the union of a male gamete and a female gamete from different individuals of the same species cultivar a cultivated plant that has been selected because it has de sirable characteristics that distinguish it from other plants of the same species; a cultivar receives a unique name cuneate wedgeshaped, with the narrow end at base cutting a part of a stem, root or other part removed from a donor plant to produce a new plant by inducing roots cyme inflorescence in which the main axis terminates in a flower, as do the secondary axes that arise alongside it cytokinin a class of plant hormone involved in cell division and growth. deciduous shedding leaves at the end of the growing season decussate opposite arrangement on a stem, at right angles to the pairs immediately above and bellow dehiscent opening spontaneously at maturity deltoid in the shape of a capital delta or equilateral triangle dense having parts very close together dentate with toothlike projections along the margin denticulate with small teeth dioecy sex expression that occurs when either female or male in dividuals are present in a population diploid having two sets of chromosomes in each cell. In organisms that reproduce sexually, one set of chromosomes is inher ited from each parent discolorous of different colour or shade above and beneath distal the region of an organ that is furthest from the point by which it is attached to the plant Glossary 196 dormancy a period of cessation of growth or development double flower a flower having many more than the usual number of petals, usually in a crowded or overlapping arrangement doubletoothed dentate with each tooth bearing smaller teeth follicle dry fruit derived from a single carpel which splits along one side only gamete a reproductive cell garriga (pl. garrigues) scrubland of low shrubs with a liking for al kaline reaction soils gene the hereditary fundamental unit, that occupies a specific location on a chromosome drupe a fleshy fruit with a stony endocarp that encloses one or few seeds, such as a plum gene flow the movement of genes among different populations that results from dispersal of gametes and seeds elliptic narrowed at ends and widest at or near the middle genetic drift fluctuations in the frequency of the appearance of a gene among generations; these changes occur by chance rather than by natural selection and their effects are most marked in very small, isolated populations effective population size the average number of individuals in a population that ac tually contribute genes to succeeding generations by mat ing; this number is generally rather lower that the census number because there is a large differences in reproduc tive success between individuals emarginate with a shallow notch at the apex endocarp the innermost layer of the fruit wall entire not broken up into teeth or lobes entomophilous pollinated by insects etiolation phenomenon that occurs when plants or part of plants are grown in either partial or complete absence of light, char acterised by much more rapid elongation and pale yellow coloration of the organs evapotranspiration the process of moisture transfer from the earth to the at mosphere through the evaporation of water and transpi ration from plants explant an organ or tissue excised from a donor plant that is used to initiate an in vitro culture fascicle cluster of shortstalked leaves or flowers growing closely together filament a thready structure that bears the anther in the stamen genetic diversity the totality of different genes in a group of individuals or species genetic transformation modification of the genome through the addition of DNA from a cell of a different genotype genetic variation the differences observed among individuals within a partic ular population or between populations, due to their genes genome complete set of genes in a set of chromosomes genotype the genetic constitution of an organism germination capacity percentage of seeds which produce normal seedlings in relation to the total number of seeds of a sample taken from a seed lot gibberellic acid a hormone obtained from the fungus Gibberella fujikuroi glabrescent nearly glabrous glabrous smooth, lacking hairs glandule a minute secreting part or appendage glandulose having glandules 197 Glossary DNA deoxyribonucleic acid consists of two long chains of nu cleotides linked together in a structure resembling a lad der twisted into a spiral glaucous slightly bluish shade of light green in colour glaucescent tending towards glaucous globose spherical glomerule a compact, globose inflorescence with many sessile or sub sessile flowers gynodioecy sex expression that occurs when female and hermaphro dite individuals are present in a population hairy having hairs haploid having a single set of chromosomes hardwood cutting a lignified cutting, taken from the previous season’s growth of in dormant woody plants head a dense cluster of sessile flowers attached to a receptacle herbaceous not woody or membranous. Leaflike texture hermaphroditism having flowers with both male and female reproductive parts hispid with short, stiff or bristly hairs hololophic nectariferous disc divided into five lobes, each lying be tween two stamens that may be either free from or united to the disc; the lobes may be entire or have an obtuse, truncate, retuse or emarginate apex hybridisation crossbreeding between individuals of different species hypodiscal beneath the nectariferous disc in vitro aseptic culture under laboratory conditions inbreeding the breeding or mating of related individuals inbreeding depression the reduction in vigour often observed in progeny from mating between close relatives indehiscent not splitting open at maturity indolebutyric acid a synthetic hormone promoting elongation of stems and roots (IBA) indumentum a covering of hairs, scales, glandules, etc. found on the surface of different organs inflorescence a branching flowering system, its branches ending in flowers infructescence a fruiting structure that consists of more than a single fruit, produced by an inflorescence inoculation the process of introducing a microorganism into a plant internode the portion of a stem between two successive levels of in sertion of leaves or leaf pairs interspecific occurring between different species intraspecific occurring between individuals or populations of the same species introgression the incorporation of genes of one species into the genetic information of another through hybridisation followed by backcrossing involucre a series of bracts below or around a flower or an inflorescence keeled having a ridge or shaped like a ridge or the keel of a ship laciniate deeply cut into irregular, narrow segments lanate having woolly hairs lanceolate like the blade of a lance, tapering towards the apex and towards the base lateral bud axillary bud layer a shoot which, while still attached to the plant, forms roots when it comes into contact with a substrate. The layered section, with its roots, can then be separated from the original plant leaflet one of the blades or leaflike divisions of a compound leaf Glossary 198 lignify to turn into wood or become woody linear long and narrow with parallel or almost parallel margins lobe a rounded projection lobule a subdivision of a lobe long shoot major shoot that has long internodes loose having parts widely separated from one another macronutrient a mineral used by plants in a relatively large amounts mallet cutting a hardwood cutting that includes a short section of stem of the previous season’s growth margin edge of a laminar organ (such as a leaf) maquis droughtadapted Mediterranean scrubland composed of shrubs and small trees with thick, coriaceous, perennial leaves or spiny foliage. meiosis the process of cell division in sexually reproducing organ isms that involves the reduction in the number of chro mosomes and some exchange of genetic material, leading to the production of genetically different, haploid repro ductive cells meristem Plant tissue whose cells actively divide to form new tissues that cause the plant to grow micronutrient a mineral used by plants in very small amounts micropropagation plant tissue culture molecular marker a gene or a specific fragment of DNA that can be used to identify an organism, species or strain or a phenotypic trait associated with it monoecy sex expression that occurs when the same individual has separate female and male flowers mucro a short point muticous lacking a mucro natural selection the process by which favourable heritable traits become more common in successive generations navicular shaped like a boat nectariferous disc a nectarsecreting disklike or ringlike glandulose out growth from the receptacle inside the flower nectary a gland that secretes nectar, usually located at the bases of insectpollinated flowers node the point on a stem where a leaf is attached oblanceolate reverse lanceshaped, broadest in upper third and taper ing from the middle towards the base oblong longer than broad with margins nearly parallel for most of their length obovate ovate but with the terminal half broader than the basal half obtuse blunt, not acute opposite arrangement in which leaves arise in pairs on either side of each node orbicular circularshaped ortet the original plant from which a clone is started through vegetative propagation oval having the shape of an ellipse ovary the ovulebearing lower part of a pistil that ripens into a fruit ovate with the outline of an egg having the broader end at base palmate having three or more leaflets or lobes radiating from one point, like the fingers of a hand 199 Glossary legume dry fruit derived from a single carpel splitting along both sides into two valves when ripe palmatifid palmately divided up to halfway to the base panicle a raceme composed of racemes, frequently pyramidshaped paniculiform cyme a cyme resembling a panicle papilla tiny conical outgrowth from an epidermal cell papillose having papillae paralophic nectariferous disc divided into four or five lobes with trun cate apex, united to one stamen parthenocarpy the production of fruit without fertilisation patent spreading from the stem at an open angle paucidentate with few teeth pedicel stalk of each flower in a compound inflorescence peduncle stalk of a solitary flower or of an inflorescence pentagonal resembling a pentagon, having five sides pinnate having divisions or segments arranged on each side of a common axis pinnatisect deeply divided pinnately to nearly the middle vein pistil the female organ of a flower, comprising the stigma, style and ovary; it consists of a single carpel or of several carpels fused together plasticity the ability of a single genotype to give rise to a spectrum of phenotypes. Plasticity may occur as different pheno types among different individuals of the same genotype, different phenotypes within the lifetime of a single indi vidual, or different phenotypes in response to specific en vironmental conditions poly prefix denoting many pollen sac structure where pollen grains are produced polyploid having three or more sets of chromosomes pome a simple fruit that has several seed chambers developed from a pluricarpelar ovary embedded in a fleshy part de veloped from the receptacle pentamerous having flower parts, such as petals, sepals or stamens, in sets of five population a group of individuals of the same species, occupying a particular geographic area, that experiences total or great reproductive isolation perianth the envelope of a flower, consisting of the calyx and the corolla pruinose having a pale grey waxy dustlike coating perennial leaf leaf lasting for more than one vegetative period persistent not falling off pH potential of hydrogen; a measure of the acidity or alka linity of a solution phenology the relationship between a periodic biological phenome non and climatic conditions; the time frame of any sea sonal biological phenomenon phenotype the observed characteristics of an individual, determined by its genotype interacting with the environment in which it is growing provenance a specific geographical location within the distribution range of a species puberule minutely pubescent pubescent having short soft hairs pulverulent covered with a fine powder purity the percentage composition by weight of pure seeds in relation to the total weight of a sample taken from a seed lot; the sample is separated into three components: pure seeds, seeds of other species and inert matter Glossary 200 raceme a simple inflorescence having stalked flowers arranged al ternately along a single axis racemiform cyme a cyme resembling a raceme but with the axis ending in a flower rachis the main axis of an inflorescence or of a pinnately com pound leaf ramet an individual member of a clone receptacle the expanded tip of a flower stalk that bears the floral structures or the group of flowers in some inflorescences region of provenance an area demarcated for a species or group of species in which stands or seed sources showing similar phenotypic or genetic characters are found, or an area or group of areas with uniform or similar ecological conditions reniform kidneyshaped reproductive material fruits, seeds, plants and part of plants (buds, cuttings, ex plants, embryos, layers, roots, scions, sets and other parts) for the production of planting stocks retuse notched slightly at an obtuse apex revolute with the margins curling under rhizomatous having rhizomes rhizome a horizontal, usually underground stem that often sends out roots and shoots rhytidome dead tissues, generally rough and cracked, that can cover the trunk, branches and roots of trees and shrubs samara a one seeded indehiscent dry fruit with a winglike structure scarious thin, dry and membranous, not green scion part of a plant for grafting into another plant scabrid rough to touch due to minute, hard projections seed orchard a plantation of selected clones or families which is iso lated or managed so as to avoid or reduce pollination from outside sources, and managed so as to produce frequent, abundant and easily collected crops of seeds seed source trees within an area from which fruits and seeds are collected selfcompatible capable of selffertilisation selffertilisation fertilisation by the union of male and female gametes from the same individual selfincompatible incapable of selffertilisation semi prefix denoting a half or that something is halfdone semihardwood cutting a stiff, partially lignified cutting taken from the new growth of woody plants during the growing season sepal one of the parts of the outer whorl of a flower, usually greenish serial cutting a method of propagation by which cuttings, once rooted, are divided the following year to produce a greater num ber of cuttings sericeous covered with fine, short hairs, somewhat shiny, resembling silk serrate sawtoothed, with acute teeth pointing towards the apex serrulate minutely serrate sessile lacking a stalk and attached directly at the base set oneyearold shoot from a stool, used to obtain cuttings set of chromosomes the group of qualitatively different chromosomes inher ited as a unit from one parent 201 Glossary quantitative feature a characteristic that shows continuous phenotypic varia tion; it often depends upon the cumulative action of many genes, each of which produces only a small effect, and may also be influenced significantly by environmental effects seta a stiff hair subspecies taxonomic category immediately below species short shoot lateral shoot that has very short or no internodes sulcate having long, narrow furrows or grooves setose bearing setae simple inflorescence an inflorescence with singleflowered branches simple leaf not lobed or divided sinuate having a wavy margin softwood cutting a cutting taken from a not already lignified soft stem or tip of a woody plant solitary flower flower not arranged on an inflorescence spatulate shaped like a spatula spike a raceme in which the flowers are all sessile stamen the male organ of a flower, comprising the filament and the anther stand delineated population of trees possessing at least a mod erate degree of uniformity in composition, structure and quality stellate starshaped stigma top part of the pistil, on which pollen is deposited at pol lination subulate tapering very gradually upwards to a fine point sympatry the occurrence of species or subspecific taxa in the same area or in overlapping areas synlophic nectariferous disc deeply divided into four or five, some times three, lobes with attenuate apexes united to one stamen, giving the impression that the stamen itself has a broad base taxon (pl. taxa) a group of organisms forming any taxonomic category (e.g. family, genus or species) TDR a probe used to measure soil water content (time domain reflectometry) terete circular in crosssection terminal appearing at the end of a stem or a similar part tetramerous having flower parts, such as petals, sepals or stamens, in sets of four tetraploid having four sets of chromosomes thalweg line connecting the lowest parts of a river bed or valley thermophile native of warm climes; unable to withstand cold stipe stalk of a pistil thyrse a dense inflorescence comprising a racemose central axis with lateral branches ending in cymes stipule a leafy appendix at the base of a petiole, usually occurring in pairs trichome a hair, bristle, papilla or scalelike outgrowth from an epi dermal cell stipitate carried on a stipe style the slender part of a flower pistil, extending from the ovary to the stigma sub prefix denoting somewhat, slightly, rather, or under tomentose totally covered with hairs tripinnate three times pinnate; a pinnate leaf with bipinnately di vided segments trullate ovate but margins straight; trowelshaped Glossary 202 truncate appearing to terminate abruptly, as though an end or point has been cut off turion a thick fleshy young shoot or sucker rising from a subter ranean bud umbel a usually umbellashaped inflorescence in which all the pedicels arise from about the same point at the tip of the peduncle; the outer flowers open before the inner ones unguiculate narrowed into a claw unisexual having either stamens or pistils but not both valve one of the sections into which a legume or other dehiscent fruit splits variety a taxonomic subdivision of a species consisting of a group of individuals that differ from others of the same species in minor but heritable characteristics vein one of the vascular bundles or ribs that form the branch ing framework of conducting and supporting tissues in a leaf or other expanded part viability the capacity of a seed to germinate under favourable con ditions; it is usually expressed as the percentage of seeds having a live embryo in relation to the total number of seeds of a sample taken from a seed lot vicariant each of the species in different, more or less distant geo graphical areas that play the same ecological role and dis play only limited morphological differences from each other whorl the arrangement of three or more leaves, petals or other organs radiating from a single node 203 Glossary zonal having a geographic distribution that is mainly determined by climate 9 788448 249656 “Printed on Ecological Paper”