Isoberlinia angolensis (PROTA)
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Introduction |
| General importance |  
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| Geographic coverage Africa |
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| Geographic coverage World |
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| Medicinal |
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| Timber |
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| Fuel |
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Isoberlinia angolensis (Benth.) Hoyle & Brenan
- Protologue: Kew Bulletin 4(1): 78 (1949).
- Family: Caesalpiniaceae (Leguminosae - Caesalpinioideae)
Origin and geographic distribution
Isoberlinia angolensis occurs from southern DR Congo to Tanzania, Malawi, Zambia and Angola; it has also been recorded from southern Sudan.
Uses
The wood of Isoberlinia angolensis, known as ‘mutondo’, is suitable for heavy construction and flooring, interior trim, vehicle bodies, railway sleepers, poles, furniture and ladders. It is also used as firewood and for charcoal production. In Zambia the wood is used for mine props and the charcoal in smelting copper.
Painted fruits are sold in the curio trade. In Angola a tea from the root is drunk against persistent cough, while bark and leaves are used in the treatment of wounds. In Zambia pounded leaves and twigs are added to drinking water of chicken against Newcastle disease. In Angola the bark is occasionally used for tanning in leather production. The flowers are rich in nectar and are much visited by honey bees. Edible caterpillars can be collected from the leaves.
Production and international trade
The wood is only used and traded locally.
Properties
The heartwood is pinkish brown, sometimes with a grey hue, and not always distinctly demarcated from the paler, up to 2.5 cm wide sapwood. The grain is wavy or interlocked, texture coarse. The wood is quite heavy, with a density of about 820 kg/m³ at 12% moisture content, and hard. It air dries slowly with a moderate tendency to distortion and surface checking. The shrinkage rates are moderate, from green to oven dry about 5.6% radial and 6.9% tangential. The wood is difficult to work with hand tools, but moderately easy with machine tools. It has a considerable blunting effect on tool edges. The grain has a tendency to pick up upon planing; a 20° cutting angle is recommended. A filler is needed to get a smooth finish. The wood glues well, but is not suitable for moulding or turnery. It is moderately durable, being liable to attacks by termites, Lyctus borers and marine borers. The heartwood and inner sapwood are resistant to impregnation with preservatives, the outer sapwood is permeable.
A seed sample from Zambia contained 3% oil.
Description
- Shrub or small to medium-sized tree up to 20 m tall; bole branchless for up to 7 m, up to 50(–100) cm in diameter; bark surface fissured and scaly, grey to brown; crown rounded, with spreading branches.
- Leaves alternate, paripinnately compound with 3–4(–5) pairs of leaflets; stipules fused, caducous; petiole and rachis together 6.5–25 cm long; leaflets opposite, ovate to elliptical or oblong, (4–)7–19 cm × 2–8 cm, cuneate to rounded at base, acute to obtuse or notched at apex, glabrous to short-hairy below, pinnately veined with (8–)11–16 pairs of lateral veins. Inflorescence a terminal or axillary panicle up to 18 cm long, much-branched with ultimate branches 3–8 cm long, brown short-hairy; bracts 3–4 mm long.
- Flowers bisexual, nearly regular, 5-merous, whitish; pedicel up to 4(–15) mm long, with 2 thick bracteoles 1–1.5 cm long, finely hairy; sepals narrowly triangular, 5–7 mm long; petals nearly equal but one slightly broader and 2-lobed, obovate to oblong, 7–12 mm long; stamens 10, free, c. 2 cm long; ovary superior, hairy, with stipe, 1-celled, style slender.
- Fruit an oblong, often curved pod 19–35 cm × 6–8 cm, with fine transverse streaks, brown short-hairy to glabrous, dehiscent with 2 woody valves, few-seeded.
- Seeds rounded, flat.
Other botanical information
Isoberlinia angolensis is variable and 3 varieties have been distinguished. It has been much confused with Isoberlinia tomentosa (Harms) Craib & Stapf.
Isoberlinia comprises 5 species and occurs in the Sudanian and Zambezian woodlands, but one species, Isoberlinia scheffleri (Harms ex Engl.) Greenway, in rainforest in eastern Tanzania. It is called ‘mbarika’ in Swahili and closely resembles Isoberlinia angolensis, but it is a large, evergreen tree up to 45 m tall with straight but often buttressed and fluted bole. Its reddish brown wood is fairly heavy, with a density of 740–830 kg/m³ at 12% moisture content, and hard, but susceptible to termites and borers which limits its use; it is used for tool handles, as firewood and for charcoal production. Formerly the fruit valves were used as shoe soles. Isoberlinia scheffleri is classified in the IUCN Red List as vulnerable.
Ecology
Isoberlinia angolensis occurs in deciduous woodland and open forest on gravelly, lateritic or muddy soils, often gregariously, sometimes dominant or co-dominant, at 600–2100 m altitude.
Management
Seed damage caused by beetle larvae before dispersal of the seed can be very high; predation rates of 85% have been observed in Zambia, but were much lower in years with high seed production. Germination can be improved by soaking seed in hot water. Wildlings are sometimes collected for planting. On coppicing, Isoberlinia angolensis produces a high number of shoots, indicating a good recruitment potential. Trees respond well to pollarding and lopping. Care should be taken during felling because boles are often hollow. In Zambia bark harvesting for medicinal purposes caused severe deterioration of the wood, displaying extensive tissue discoloration, increased insect infestation and profuse gum exudation. Covering the wound site with mud considerably protected the trees from wood deterioration.
Genetic resources
Isoberlinia angolensis is widespread and locally common. There are no indications that it is in danger of genetic erosion.
Prospects
Isoberlinia angolensis will remain a locally important source of timber, firewood and charcoal. Systems for the sustainable management of the woodlands in which it occurs need to be developed.
Major references
- Brenan, J.P.M., 1963. The species of Isoberlinia (Leguminosae). Kew Bulletin 17: 219–226.
- Brenan, J.P.M., 1967. Leguminosae, subfamily Caesalpinioideae. In: Milne-Redhead, E. & Polhill, R.M. (Editors). Flora of Tropical East Africa. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. 230 pp.
- Brummitt, R.K., Chikuni, A.C., Lock, J.M. & Polhill, R.M., 2007. Leguminosae, subfamily Caesalpinioideae. In: Timberlake, J.R., Pope, G.V., Polhill, R.M. & Martins, E.S. (Editors). Flora Zambesiaca. Volume 3, part 2. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 218 pp.
- Chilufya, H. & Tengnäs, B., 1996. Agroforestry extension manual for northern Zambia. Regional Soil Conservation Unit, Nairobi, Kenya. 120 + 124 pp.
- Malaisse, F., 1997. Se nourir en forêt claire africaine. Approche écologique et nutritionnelle. Les presses agronomiques de Gembloux, Gembloux, Belgium & CTA, Wageningen, Netherlands. 384 pp.
Other references
- Baerts, M. & Lehmann, J., 2012. Isoberlinia angolensis. [Internet] Prelude Medicinal Plants Database. Metafro-Infosys, Royal Museum for Central Africa, Tervuren, Belgium http://www.metafro.be/prelude. March 2012.
- Bryce, J.M., 1967. The commercial timbers of Tanzania. Tanzania Forest Division, Utilisation Section, Moshi, Tanzania. 139 pp.
- Chidumayo, E.N., 1994. Effects of wood carbonization on soil and initial development of seedlings in miombo woodland, Zambia. Forest Ecology & Management 70(1/3): 353–357.
- Chidumayo, E.N., 1997. Fruit production and seed predation in two miombo woodland trees in Zambia. Biotropica 29(4): 452–458.
- Chungu, D., Muimba-Kankolongo, A., Roux, J. & Malambo, F.M., 2007. Bark removal for medicinal use predisposes indigenous forest trees to wood degradation in Zambia. Southern Hemisphere Forestry Journal 69(3): 157–163.
- Gunstone, F.D., Taylor, G.M., Cornelius, J.A. & Hammonds, T.W., 1968. New tropical seed oils. II. Component acids of leguminous and other seed oils. Journal of the Science of Food and Agriculture 19(12): 706–709.
- Handavu, F., Syampungani, S. & Chisanga, E., 2011. The influence of stump diameter and height on coppicing ability of selected key Miombo woodland tree species of Zambia: a guide for harvesting for charcoal production. Journal of Ecology and the Natural Environment 3(14): 461–468.
- Lovett, J.C., Ruffo, C.K. & Gereau, R.E., 2003. Field guide to the moist forest trees of Tanzania. [Internet] Centre for Ecology Law and Policy, Environment Department, University of York, York, United Kingdom. http://celp.org.uk/ projects/ tzforeco/. March 2012.
- van Vuuren, N.J.J., Banks, C.H. & Stohr, H.P., 1978. Shrinkage and density of timbers used in the Republic of South Africa. Bulletin No 57. South African Forestry Research Institute, Pretoria, South Africa. 55 pp.
- Wilczek, R., Léonard, J., Hauman, L., Hoyle, A.C., Steyaert, R., Gilbert, G. & Boutique, R., 1952. Caesalpiniaceae. In: Robyns, W., Staner, P., Demaret, F., Germain, R., Gilbert, G., Hauman, L., Homès, M., Jurion, F., Lebrun, J., Vanden Abeele, M. & Boutique, R. (Editors). Flore du Congo belge et du Ruanda-Urundi. Spermatophytes. Volume 3. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 234–554.
Author(s)
- L.P.A. Oyen, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
Correct citation of this article
Oyen, L.P.A., 2012. Isoberlinia angolensis (Welw. ex Benth.) Hoyle & Brenan. [Internet] Record from PROTA4U. Lemmens, R.H.M.J., Louppe, D. & Oteng-Amoako, A.A. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. Accessed 22 April 2026.
- See the Prota4U database.