Dracaena in West Africa

AGRICULTURAL UNIVERSITY WAGENINGEN PAPERS 84-1 (1984) DRACAENA IN WEST AFRICA J.J. BOS Department of Plant taxonomy Agricultural University Wageningen, The Netherlands Received 6-VI-1984 Date of publication 17-X-1984 On Agricultural University Wageningen, The Netherlands 1984 ^.-> CIP-gegevens Bos,J . J. Dracaena in West Africa/J. J. Bos- Wageningen: Agricultural University. - (Agricultural University Wageningen Papers; 84-1(1984)) Ook verschenen alsproefschrif t Wageningen.- Met reg. ISBN 90-6754-058-7 SISO 588UD C 582.572(66) Trefw.: Dracaena; plantentaxonomie; West-Afrika. ISBN 90-6754-058-7 © Agricultural University, Wageningen, theNetherlands , 1984. No part of this publication, apart from abstract, bibliographic data and brief quotations embodied incritica l reviews,ma y be reproduced, re-recorded or published in any form including print, photocopy, microform, elektronic or elektromagnetic record without written permission from the publisher Agricultural University, P.O. Box9101,670 0H BWageningen , the Netherlands. Printed in theNetherland s by Drukkerij Veenman b.v., Wageningen. CONTENTS INTRODUCTION AND ACKNOWLEDGEMENTS GENERAL P\RT: History ofE racaen a inWes t Africa. 3 Phytogeography 4 Habit and Growth. 5 Morphology. 7 Flowering 8 Phylogeny 10 TAXONOMIC TREATMENT: Genusdiagnosi s 14 Keyt oth especie s inWestAfrica 17 Speciesdia g loses 19 APPENDIX: Dracaena dijaco (L.)L 120 Dracaenasp . .cf.D.nyangensisPellegri n 120 Dracaena saposchnikowi iRege l 121 Speciesexclüdend a 121 Nomina rejii:iend a 122 REGISTER 124 PHOT. 1.Dracaena arborea (Willd. ) Link fruiting at WAG (photograph J. W. MUGGE). INTRODUCTION AND ACKNOWLEDGEMENTS The present publication isth ethir d revision ofDracaena for WestAfric a (after those by HUTCHINSON and HEPPER) and is part of a monograph of the genus. It is based on almost all herbarium extant during the years the analyses were made. These a îalyses were supplemented by observations on living plants in the field and g: •own in the greenhouse at WAG for many successive years. Of the 23tax areccj> : gnized, seventeen could be studied in this way. Asth egenu s hasenjoye d wideinteres ti nornamenta l horticulture, particularly from the middlle of the nineteenth century on, the amount of literature involved isvas t and van£swidel y in character. Nomenclature is hampered by the fact that about 2200 names are involved, approximately 1600 combinations in Dracaena alone, of which but one fifth was directly accessible through Index Kewensis. A conservative estimate of the number of dispnet species in Dracaena approximates 60 and fortunately not all of these are burdened with excessive synonymy. A substantial number of these names idee s not refer to Dracaena species but has to be considered in the synonymy of the iextremel y variable Cordylinefruticosa (L.) A. Chev. Publica- tion of that syrionymy ispostpone d till a full monographical treatment of Dra- caenai spossib l e.Th e typification of thisclou d of names,i fwarranted , is usually complicated b) the inadequacy of descriptions and the absence of herbarium specimens Oftçn the described plants were very expensive specimens shown on exhibitions. West Africa as delimited for this paper, does, contrary to the Flora of West Tropical Africi , not include West Cameroun and Fernando Póo. Of the 23 sp cies recognized, two are but provisorily dealt with as they are both represent«d by a single collectionjus t within our area. Both will be treated more; comprer « nsively for the Floraso fCamerou n and Gabon. Ofth e remaining 21species ,eig ]ïh t are restricted to West Africa and three continental African spe- ciesar e revised for their entire area. Compared to the second edition of the Flora of West Tropical Africa, 13 names have been retained with more or less modified delimitations, the names of 3 species and one variety had to be changed. One species appeared to be hitherto not reo ognized in West Africa, another Central African species is for the first time corded in our area; 3 species are new to science, and another twoma y yet prove to be new. All species ;ar e figured and provided with a map of their distribution, at least in West Africa, , except one species only known by its type. A new diagnosis for the genus nd a key to the species of West Africa are added. The species are annotated and phenological information isprovide d with the specimens cit- ed. I wish to express my gratitude to the following persons and institutions: Prof. Dr. H. C. D. DE WIT for his most stimulating interest in my adventures Agric. Univ. WeigeringenPapers84-1 (1984) 1 with Dracaena, his successful efforts to enable me to study the African flora extensively in the field and his generous provisions to maintain an unmatched collection of living Dracaenas at WAG. His interest is further reflected by the photographs he provided for this publication. The collective staff and personel of the Department of Plant Taxonomy in Wageningen and among them in particular: Dr. Ir. F. J. BRETELER, Dr. Ir. J. J. F. E. DE WILDE and Dr. D. O. WIJNANDS for numerous discussions on this subject, Ir. J. C. ARENDSwho m Igreatl y appre ciate for his valiant battle to procure the Dragon's chromosomes, Mr. F. J. VAN DER LAAN, whose watchfull eye does not miss one trick of the many Dracaenas entrusted to him, Messrs. G. PEPERKAMP, W. G. A. M. SCHOLTEN and G. H. GERRITSEN for their unfaltering dedication to the living collection, Miss D. M. WASSINK for protecting my time and my manuscript, Mr. C. T. DE GROOT for procuring reference literature from where, it was asserted, it was not, Mr. J. W. MUGGE for hiscontribution s in photography, Mr.J .W . VAN STEENBERGENfo r hismeticulou s administration ofth e extensive herbarium loans, Mr. J. VAN VELDHUIZEN for his spiritual conservation, Mes-damesW . WESSEL-BRAND, Y. F. TAN, P. VERHEIJ-HAYES, J. WILLIAMSON, supervised by Miss H. G. D. ZEWALD, for the beautiful illustrations, Mrs. Dr. G. J. H. AMSHOFfo r the latin diagnoses, Mr. G. BOELEMA and Mrs. Drs. F. J. H. VAN DILST for the tricky editorial work on this manuscript, Messrs. BIHOLONG, BOULABBAH SAVADOGO, DANG, GOLL, KOUFANI, KWE- WON, MBAMBA EKITIKE, MEZILI, MPOM and many otherswh ohav e accompanied mei nth e African forests, To the Netherlands Foundation for the Advancement of Tropical Research (WOTRO) for enabling me to visit the herbaria in London and Paris, To the Directors, curators and staff of the herbaria named hereafter, who made their collections available for this study: A, ABI, B, BH, BM, BR, C, CAIM, CGE, COI, DR, E, FHI, FHO, FI, FR, G, GB, GC, GENT, GOET, GRA, GRO, H, HBG, IEC, IFE, K, L, LD, LE, LINN, LISC, LISJC, LISU, LMA, LMU, M, MADJ, MICH, MO,NBG-SAM , O,ORT , OXF, P,PR , PRC, PRE, RB,RNG , S, SRGH, TCD, U, UCI, UCJ, UPS,US ,W , WU, YA, Z. Agric. Univ. WageningenPapers 84-1 (1984) GENERAL PART HISTORY OF DRACAENA IN WEST AFRICA The trade activities on the coast of West Africa in the seventeenth century providedth e opportunity forEuropea n traders toacquain t themselves withth e flora of tropica Africa andt oprocur e interesting plants forlivin g plant collections coming vogue in Europe. In this way COMMELIN obtained Dracaena fragrans forth e Amsterdam garden from SIMON VAN BEAUMONT, aDutc h states- man who owne|d a famous plant collection at TheHagu e andwh o in his turn received this species]fro m Guinea (WUNANDS 1983). PHOT. 2. COMMÖLIN. Rariorum Plantarum Horti Medici AmstelodamensisI (1697)fig. 49 :Aloe Arborescens Africana, The earliest illustn tion of an introduction of Dracaenafra- grans(L ) Kew Gawfler (photograph J. W. MUGGE). During this period Dracaenas certainly were introduced from West Africa into South America, Brazil in particular, where they have formed a resource for repeated introductions ofcultivate d ornamental foliage plants into Europe and North Am«ric a till the present times. A brief outline of the taxonomie history of the genus hasbee n presented in a previous pap«r (BOS 1980). Early taxonomie work was based largely on living plants cultivate^ in glasshouses. Sometimes flowers and fruits were unknown and usually herbarium specimens were notconserved , noteve n ofsteril e specimens.Thi s was still the casewhe n BAKERpublishe d hismonograp h of Dracaena in 1875. His des;ription swer eofte n atleas tpartl ybase d onlivin gplant s cultivat- edi n botanical ant collectionsan d commercial nurseriesi n London. Of several taxa hedi d not know thecountr y oforigin . At that time herbarium collections containing Dracaena material from West Africa were extremely rare. AFZELIUS Agric. Univ.Wagen ngenPapers 84-1 (1984) collected five different species of Dracaena in Sierra Leone during his residence intha t country from 1792t o 1794.Dracaena mannii wa scollecte d in Senegambia in 1829 bij PERROTTET and about ten years later by HEUDELOT. Around 1860 BARTER, THOMSONan d MANN wereactiv ei nNigeria . MANN collected eight diffe rent species which is an impressive number even by today's standards. Signifi cant additions to our records of Dracaena in West Africa were not made before the last decade of the nineteenth century. The keen rivalry among the colonial powers of those days stimulated the activities of English, French and German collectors, but BAKER'S treatment of Dracaena for the Flora of Tropical Africa of 1898hardl y profited by their results. The first comprehensive treatment of Dracaena in West Africa was published in 1936 by HUTCHINSON in his Flora of West Tropical Africa. He recognized 17species , uniting several previously recognized taxa and he proposed one new species. HEPPER revised HUCHINSON'S treatment for the second edition of the Flora in 1968. He recognized 20 species, two varieties and recorded one additional imperfectly known species.

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