Journal of Tropical Forest Science 8(3): 395 -411 (1996) 395 A REVIESILVICULTURE TH F WO RESOURCD EAN E POTENTIA MIOMBA F LO O FRUIT TREE: UAPACA KIRKIANA (EUPHORBIACEAE) Mzoma R. Ngulube, Forestry Research Institute of Malawi, P.O. Box 270, Zomba, Malawi John B. Hall School of Agricultural and Forest Sciences, University College of North Wales, Bangor, LL 57 2UW, United Kingdom & . MaghembJA e International Centre Researchfor Agroforestryin (ICRAF), SADC/ICRAF Agroforestry Project, P.O. 134,Box Zomba, Malawi Received January 1995 _______ _______ ________ ________ ________ NGULUBE, M.R., HALL, J.B MAGHEMBE.& , J.A. 1996 revie silviculturA .e th wf o e and resource potential of a miombo fruit tree: Uapaca kirkiana (Euphorbiaceae). Uapaca kirkiana Mull. Arg multipurposa s i . e tropical fruit tree indigenoue th o t s miombo woodland f southero s n Afric d widelan a y distribute Angolan i d , Zaire, Burundi, Tanzania, Malawi, Mozambique, Zambia and Zimbabwe. The tree is particu- larly valued for its fruit which is a source of food and cash throughout its natural range. The wood is useful for timber, fuelwood, charcoal, agricultural implements and general carpentry. A brief account of its taxonomic position, botany, ecology distributiod an outlineds ni majoA . r par thif to s review centre silviculture th n so d ean resource potential of Uapaca kirkiana in southern Africa. The discussion draws atten- tio existino nt g gap knowledgn si researcd ean h need supporo t s enhancd an t e conservation and development of Uapaca kirkiana as a resource. Constraints to the realizatio s fulit l f potentiao n e identifiear l s incompletda e knowledge th f eo reproductive biolog breedind yan g systems, lac detailef ko d propagatio cultivad nan - tion procedures, insufficien markee t datth n ao t potentia productss it fruie d th an tf lo , and lack of appropriate processing and storage technologies. Key words: Uapaca kirkiana - taxonomy - botany - silviculture - resource potential - fruit tree - conservation - management - miombo woodlands - southern Africa NGULUBE, M.R., HALL, J.B. & MAGHEMBE, J.A. 1996. Satu ulasan mengenai potensi silvikultur dan sumber pokok buah-buahan miombo: Uapaca kirkiana (Euphorbiacea). Uapaca kirkiana Mull. Arg. adalah pokok tumbuh-tumbuhan asli tropika pelbagai guna bagi kawasan hutan jarang Afrika Selata taburannyn nda a adalah melua i Angolad s , Zaire, Burundi, Tanzania, Malawi, Mozambique, Zambin ada 396 Journal of Tropical Forest Science 8(3): 395-411 (1996) Zimbabwe. Pada keseluruhannya pokok tersebut khususnya bernilai bagi buahnya yang menjadi sumber makanan wangn da . Kayu tersebut berguna untuk balak, kayu api, arang, alat-alat pertanian dan pertukangan kayu. Satu keterangan ringkas mengenai kedudukan taksonomi, botani, ekologi dan pengagihannya telah dirangka. Bahagian utama ulasan ini menumpukan kepada potensi silvikultur dan sumber Uapaca kirkiana di Afrika Selatan. Perbincangan memberikan perhatian kepada perbezaan-perbezaan yang wujud dari segi pengetahua keperluan nda n penyelidikan untuk menyokonn gda meningkatkan pemuliharaa perkembangan nda n Uapaca kirkiana sebagai satu sumber. Hambatan-hambatan bagi merealisasikan potensi sepenuhnya telah dikenalpasti iaitu pengetahuan yang cetek mengenai pembiakan biolog sisten da i m pembiakbaikan, kekurangan prosedur-prosedur terperinci mengenai pembiakan dan penanaman, data yang tidak lengkap mengenai potensi pemasaran buah-buahan dan keluarannya, kekurangan da n teknologi pemprosesa penyimpanan nda n yang sesuai. Introduction The genus Uapaca consist of 60 species of which 49 are restricted to tropical Africa and the rest occur only in Madagascar. In tropical Africa, Uapaca species are found in both woodland and moist forests of west and southcentral Africa. The most wide- spread and best known of them, Uapaca kirkiana Muell. Arg., is a typical miombo woodland specieZambeziae th f so n Regional Centr adjacend ean t transitional centres (White 1983). It occurs naturally in Angola, Burundi, Malawi, Mozambique, Tanzania, Zaire, Zambi Zimbabwed aan . recognisew Uapacafe e th f kirkianao d importane on s i t African fruit trees with economic potential which is extensively locally utilised within the natural range (Maghembe et al. 1994). Its fruits have high nutritional values and play an important dietary role (Carr 1957, Sufi & Kaputo 1977, Malaisse & Parent 1985, Sak Msontha& i 1994), whil wooe eth usefus di r generafo l l purposes: timber, fuelwoo charcoald dan , post agriculturad san l implements (Goldsmit Carteh& r 1981) bar e rootd Th .useke an treatmenr sar dfo variouf o t s stomach disorders (Storrs 1979). Despite its abundance in the miombo region of southern Africa, accelerating deforestation (Hyde & Seve 1993) and the rarity of domesticated stands underline the need for active conservation. Aroun mane dth y expanding centre f populatioso n withi naturas nit l range, extensive replacement of forest by arable and tree crops has been responsible for substantial reduction kirkiana. U n si populations. Currently farmer intere sar - ested in U. kirkiana only to the extent that they can harvest edible fruits, wood and other products. Beyond that, the only effort made is to select trees with good fruiting characteristics like heavy fruit load, regular fruiting fruitg bi , s with good flavou leavd an r e them uncut during woodland clearing prio cultivatioo rt r no settlement. Data from ethnobotanical and socio-economic studies (Maghembe & Seyani 1991, Kwesiga & Chisumpa 1992, Grundy et al. 1993) reveal that local farmers have strong interest in the domestication of U. kirkiana as a multipurpose fruit tre o eventuallet y yield frui o supplt t growine yth g local market and cater for domestic needs. However, available data which could guide and support cultivation of U. kirkiana as a resource in southern Africa remains scattered in the published and the grey literature for any effective use. This paper Journal of Tropical Forest Science 8(3): 395-411 (1996) 397 therefore attempt provido st unifieea d existin e pooth f lo silviculturge datth n ao e resourcd an e potentia f Uapacalo kirkiana. Distributio environmentad nan l requirements Existing information on the ecology of Uapaca kirkiana has been assembled and a distributio preparep nma d (Ngulube 1995) . et al speciee .Th reportes i d from most countries within the Zambezian centre of endemism and adjacent transitional phytochoria (White 1983): Angola, Burundi, Malawi, Mozambique, Tanzania, Zaire, Zambia and Zimbabwe between latitudes 2°S and 21°S (Figure 1). Within the natural range, occurrence is related to unimodal rainfall regime with an annual rainfall range of 500-1400 mm occurring over a 4-5 months period followe lona seasoy y gddr b n lastin months7 g5- . Ove rangee rth meae ,th y nda time temperature regime is 18-29°C in the hot season and 12-24°C in winter. Typically, Uapaca kirkiana grow well-drainen i s d escarpments, mostl t altitudeya s of 500-2000 m, with infertile sand or gravelly soils of acidic reaction. Frost-free sites are most ideal. Associated woody species include Albizia, Arisophyllea, Brachystegia, Burkea, Isoberlinia, Julbernardia, Monetes, Parinari, Protea, Pericopis, Pterocarpus, Ochna othed an r Uapaca specie miombe th f so o ecozone. 40° • ° 50 ° 40 ° 30 ° 20 ° 10 ° 0 ° 10 20° Figure 1. U. kirkiana distribution 398 Journal of Tropical Forest Science 8(3): 395 - 411 (1996) Taxonomy Uapaca is a member of the family Euphorbiaceae, subfamily Phyllanthoideae in tribe Antidesmeae, and the sole representative of the subtribe Uapacinae (Webster 1975,1987). Uapaca Malagasa s i y genu e namth r sefo 'Voa-paca uses r dwa fo d an ' the Madagascar species, Uapaca thouarsii, described by Henri Baillon (1827-1895) in 1858.The genus currently has 60 species assigned to it (Radcliffe-Smith 1988, 1993), but there has been no recent revision on a continental scale and the number of distinct specie probabls si y less. Racdliffe-Smith's (1988) revisio Ease th tf no African members was the first major taxonomic account of the genus for over 50 years. The greatest diversity is in the Zaire Basin and further south in the miombo region. Many species names are used in ecological and floristic publications from considerew thino e s ar are t da bu synonym oldee th f rso names. Thus referenco et U. albida De Wild., U. dubia De Wild., U. benguelensis Muel. Arg., U. goetzei Pax, U. homblei Wild.e D greenwayi. U , Susseng., . munamensisU e D Wild., . neo-masukuDeU Wild, and U. teusczii Pax, all signify U. kirkiana. Uapaca kirkiana was named by Jean Mueller of Aargau (1864) after Sir John Kirk (1832-1922) who collected the type specimen of the species on 8 March 1862 in the Soche Hills of southern Malawi (Kirk s.n.-holotype, K). As U. kirkiana occurs in eight southern African countries mans ha t yi , vernacular names mose th , t common being wild loquat (English), msuku (Malawi, Tanzania and Zambia), nkusu (Tanzania), umhobohobo or muzhanje (Zimbabwe), matu or nt'junku (Mozambique mumbold an ) a (Angola). Botany Botanical descriptions of Uapaca kirkiana are provided by several authors (Pardy 1951, Drummond 1981, Palgrave 1981, FAO 1983), but perhaps the most compre- hensiv recene th s ei t revie Radcliffe-Smity wb h (1988) tree evergrees eTh .i r no semi-deciduous with spreading multiple branching formin densa g e rounded crown trune .Th shortks i , attaining height diameterd 5-1f an so 2m t 5-2a f so m 5c DBH bare darTh .s k i k gre grey-brownr yo , thic deepld kan y fissured. Leavee sar simple, 12-3 lon 4-2m d 6 widc galternatelm d an 4 c ean y arrange clusterdn i e th t sa tips of the branches (Figure 2). Knowledg phenologicae th f eo l aspects, reproductive biolog breedind yan g system incompletes si e specieTh . dioecious si thereford san e outcrossinge Th . unisexual inflorescence originates from axillary positions among the leaves or more often below them on the previous season's wood of the branchlets in both male and female trees.