Phyllocosmus africanus (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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| Fruit |
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| Medicinal |
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| Timber |
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| Fuel |
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| Food security |
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Phyllocosmus africanus (Hook.f.) Klotzsch
- Protologue: Abh. Königl. Akad. Wiss. Berlin 1856: 232 (1857).
- Family: Ixonanthaceae
Synonyms
- Ochthocosmus africanus Hook.f. (1848).
Origin and geographic distribution
Phyllocosmus africanus occurs from Guinea Bissau to the Central African Republic and DR Congo.
Uses
The wood is used for poles and posts in hut and house building, and for carpentry. It is suitable for hydraulic construction work, flooring, mine props, ship building and railway sleepers, but not recommended for joinery, interior trim, furniture, musical instruments, toys, novelties, carvings and turnery. The pliable twigs are used to make traps for game. The wood is considered a good firewood and is also popular for charcoal production, especially in demand by traditional blacksmiths.
The bark is used in traditional medicine. Bark decoctions are taken to treat diarrhoea, dizziness, stiffness and dysmenorrhoea, and as anodyne.
Production and international trade
The wood of Phyllocosmus africanus is only used locally and not traded on the international timber market.
Properties
The heartwood is brown to reddish brown and distinctly demarcated from the fairly wide, yellowish brown sapwood. The grain is straight or slightly interlocked, texture fine. Quarter-sawn surfaces show darker streaks or a ribbon figure. The wood contains some gum.
The wood is heavy, with a density of 915–965 kg/m³ at 12% moisture content, and hard but rather brittle. It should be air dried with care to avoid serious degrade. The rates of shrinkage are very high, from green to oven dry about 9.2% radial and 14.3% tangential. It is recommended to quarter-saw logs before drying. Once dry, the wood is unstable in service.
At 15% moisture content, the modulus of rupture is 180–210 N/mm², compression parallel to grain 68–79 N/mm², shear 4 N/mm², cleavage 22.5 N/mm and Chalais-Meudon side hardness 6.8. The wood saws slowly and does not work easily, but it can be planed and finished to a smooth surface. It holds nails well, although it has a slight tendency to split. It is moderately durable, being moderately resistant to fungi but quite resistant to termite and marine borer attacks. The sapwood is susceptible to Lyctus.
Description
- Evergreen large shrub or small to medium-sized tree up to 20(–35) m tall; bole branchless for up to 17 m but usually much shorter, usually straight and cylindrical, up to 80(–100) cm in diameter, often with many adventitious shoots at base; bark surface slightly longitudinally fissured, with numerous small lenticels, greyish to nearly black, inner bark fibrous, reddish to dark brown; crown large, with slightly sinuous and drooping branches; twigs glabrous.
- Leaves alternate, simple; stipules minute, caducous; petiole up to 0.5 cm long; blade ovate to elliptical or obovate, 5–18 cm × 2–6.5 cm, cuneate at base, acuminate at apex, with glandular teeth at margins towards apex of leaf, papery, glabrous, pinnately veined with 5–7 pairs of lateral veins.
- Inflorescence an axillary raceme up to 10 cm long, short-hairy.
- Flowers bisexual, regular, 5-merous; pedicel 1–3 mm long; sepals slightly fused at base, ovate-oblong, c. 1.5 mm long; petals free, ovate-oblong, 3–4 mm long, whitish to yellowish; stamens alternating with petals, slightly fused at base, up to 5 mm long; ovary superior, ovoid, c. 0.5 mm long, style 3–4 mm long, stigma 5-lobed.
- Fruit an ovoid to nearly globose capsule 4–6 mm × 2.5–5 mm, dehiscent with 5 valves, 1–3-seeded, with persistent sepals and petals at base.
- Seeds ellipsoid, c. 3 mm long, enclosed by a reddish aril.
- Seedling with epigeal germination; hypocotyl 2–4 cm long, epicotyl very short; cotyledons leafy, elliptical, 6–8 mm long; first leaves alternate.
Other botanical information
In Côte d’Ivoire trees usually flower in June–August, but they can also be found flowering in December–March. The flowers are fragrant and visited by flies, which are probably the main pollinators. Fruits take about 3 months to ripen after flowering. The seeds, with their reddish arils, are eaten by birds, which serve as seed dispersers.
Phyllocosmus comprises about 5 species and is restricted to Africa. It has long been included in Ochthocosmus, which is now considered to be restricted to tropical America.
Phyllocosmus lemaireanus
Phyllocosmus lemaireanus (De Wild. & T.Durand) T.Durand & H.Durand (synonym: Ochthocosmus lemaireanus De Wild. & T.Durand) is a shrub or small tree up to 10(–20) m tall, occurring in southern DR Congo, Tanzania, Malawi, Zambia, Angola and northern Mozambique. Its wood is used for poles in house building and as firewood. Twigs are used as tooth brush, and the smoke from the wood is inhaled to treat colds, cough and sore eyes. Root decoctions are taken as vermifuge.
Ecology
Phyllocosmus africanus occurs in various lowland forest types up to about 500 m altitude, from rather dry to moist forest, periodically inundated forest and gallery forest, sometimes even in wooded savanna and on termite mounds in savanna. In the forest, it is often an understorey tree.
Management
Fruits are usually picked from the tree before they open, and the small seeds are collected from the dehisced fruits after drying in the shade. The germination rate is 30–40%; seeds start germinating 3–6 weeks after sowing. Seedlings prefer shade. In timber production forest, Phyllocosmus africanus is often considered a weedy species, which was formerly sometimes killed by girdling or poisoning, e.g. by sodium arsenite. The tree boles are often small and short, yielding limited amounts of wood, but a bole of 17 m long with a diameter of 70 cm felled in DR Congo yielded 5.5 m³ of wood.
Genetic resources
Phyllocosmus africanus is widespread and locally common in various forest types and is not exploited on a large scale. Consequently, it is not liable to genetic erosion.
Prospects
The boles are usually too small to be of interest for commercial timber exploitation. Moreover, the wood is rather difficult to dry, saw and work. Phyllocosmus africanus and other Phyllocosmus species will remain of some interest for local applications, especially for poles in construction.
Major references
- Badré, F., 1972. Ixonanthaceae. Flore du Cameroun. Volume 14. Muséum National d’Histoire Naturelle, Paris, France. pp. 57–63.
- Bolza, E. & Keating, W.G., 1972. African timbers: the properties, uses and characteristics of 700 species. Division of Building Research, CSIRO, Melbourne, Australia. 710 pp.
- Burkill, H.M., 1994. The useful plants of West Tropical Africa. 2nd Edition. Volume 2, Families E–I. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 636 pp.
- Fouarge, J., Gérard, G. & Sacré, E., 1953. Bois du Congo. Institut National pour l’Etude Agronomique du Congo belge (INEAC), Brussels, Belgium. 424 pp.
- Wilczek, R. & Boutique, R., 1958. Linaceae. 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 7. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 29–53.
Other references
- Aubréville, A., 1959. La flore forestière de la Côte d’Ivoire. Deuxième édition révisée. Tome premier. Publication No 15. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 369 pp.
- Badré, F., 1973. Ixonanthaceae. Flore du Gabon. Volume 21. Muséum National d’Histoire Naturelle, Paris, France. pp. 55–62.
- Chilufya, H. & Tengnäs, B., 1996. Agroforestry extension manual for northern Zambia. Regional Soil Conservation Unit, Nairobi, Kenya. 120 + 124 pp.
- de Koning, J., 1983. La forêt de Banco. Part 2: La Flore. Mededelingen Landbouwhogeschool Wageningen 83–1. Wageningen, Netherlands. 921 pp.
- Hawthorne, W.D., 1995. Ecological profiles of Ghanaian forest trees. Tropical Forestry Papers 29. Oxford Forestry Institute, Department of Plant Sciences, University of Oxford, United Kingdom. 345 pp.
- Hawthorne, W. & Jongkind, C., 2006. Woody plants of western African forests: a guide to the forest trees, shrubs and lianes from Senegal to Ghana. Kew Publishing, Royal Botanic Gardens, Kew, United Kingdom. 1023 pp.
- Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 pp.
- Normand, D. & Paquis, J., 1976. Manuel d’identification des bois commerciaux. Tome 2. Afrique guinéo-congolaise. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 335 pp.
- Savill, P.S. & Fox, J.E.D., 1967. Trees of Sierra Leone. Forest Department, Freetown, Sierra Leone. 316 pp.
- Tailfer, Y., 1989. La forêt dense d’Afrique centrale. Identification pratique des principaux arbres. Tome 2. CTA, Wageningen, Pays-Bas. pp. 465–1271.
Author(s)
- R.H.M.J. Lemmens, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands
Correct citation of this article
Lemmens, R.H.M.J., 2012. Phyllocosmus africanus (Hook.f.) Klotzsch. In: 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 16 September 2026.
- See the Prota4U database.