Maranthes glabra (PROTA)

The wood of Maranthes glabra is considered difficult to work and of little value for carpentry, but useful for purposes for which it can be processed green. It is suitable for heavy construction, particularly for naval construction, flooring, mine props, vehicle bodies, railway sleepers, poles, piles and agricultural implements. In Sierra Leone it has been used for making canoes. In Ghana it is used for beams and stakes, and provides an excellent, though expensive firewood.

The oily seeds are eaten in Côte d’Ivoire and Cameroon. Bark macerations or decoctions are widely used in traditional medicine to treat dysentery, diarrhoea, anaemia, and as tonic and anodyne, whereas bark decoctions are also applied as a wash to treat chronic itch or scabies. Bark powder is applied to burns. Powdered roots are added to mixtures for the treatment of skin complaints in humans as well as livestock. The fruit is used in DR Congo as bait in traps for red river hogs and antelopes.

Production and international trade

The wood of Maranthes glabra is used and traded locally, but is of no importance in international trade.

Properties

The heartwood is pink or brown with a pink tinge, sometimes with attractive streaks, and clearly demarcated from the white to yellow-brown sapwood. The grain is variable, texture rather coarse. The wood has a faint smell of honey when freshly cut, which fades on drying.

The wood is heavy, with a density of 1060 kg/m³ at 12% moisture content, and very hard. It is difficult to dry and air-drying before kiln-drying is advisable. Severe distortion may occur especially in thicker boards. The rates of shrinkage are high, from green to oven dry 6.8% radial and 13.0% tangential. At 12% moisture content, the modulus of rupture is 202 N/mm², modulus of elasticity 17,850 N/mm², compression parallel to grain 101 N/mm², shear 11 N/mm², cleavage 23 N/mm and Chalais-Meudon side hardness 13.7.

The wood is very difficult to saw and work with both hand and machine tools. Because of the high silica content (up to 2.8%), it has a strong blunting effect on saw teeth and cutting edges, but it can be planed to a fairly smooth surface. For nailing, pre-boring is required. The wood is not suitable for turnery or veneer making. The heartwood is fairly resistant to termites and marine borers. It is resistant to impregnation with preservatives, the sapwood is fairly permeable.

Description

Evergreen medium-sized tree up to 30(–40) m tall; bole branchless for up to 20 m, usually straight and cylindrical, but sometimes bent, twisted or gnarled, up to 80(–150) cm in diameter, sometimes with buttresses up to 2 m high; bark surface rough, flaking off in irregular scales, orange-grey to reddish grey, inner bark thick, granular, pinkish brown to dark red, sometimes with white streaks, with some colourless to pinkish or yellowish exudate turning red; crown flattened, dark green, with sinuous, more or less upright main branches; twigs initially sparsely hairy, soon becoming glabrous.
Leaves arranged spirally, simple and entire; stipules fused at base, c. 1 mm long, early caducous; petiole thin, 0.5–1 cm long; blade elliptical, 6–12(–14) cm × 2.5–5.5(–7.5) cm, cuneate and with 2 glands at base, acuminate at apex, leathery, glabrous, pinnately veined with 5–6(–8) pairs of lateral veins.
Inflorescence an umbel-like panicle up to 8 cm long and 50 cm wide, strongly branched, short-hairy, many-flowered.
Flowers bisexual, slightly zygomorphic, 5-merous; pedicel 2–6 mm long; receptacle obconical, curved, 3–5 mm long; sepals obovate-orbicular, c. 3 mm long; petals obovate-orbicular, up to 6 mm long, creamy white; stamens c. 20, free, up to 1.5 cm long, anthers orange; ovary superior, inserted laterally near apex of receptacle, 2-celled, style long and slender, curved.
Fruit a fleshy, ellipsoid to obovoid drupe 3.5–6 cm × 2.5–4 cm, slightly flattened, narrowed at base, obtuse at apex, glabrous, greenish yellow turning brown to black, usually 2-seeded.
Seeds oily.
Seedling with epigeal germination; hypocotyl 6–7 cm long, epicotyl 3–5 cm long, glabrous; cotyledons thick and fleshy, 3–4 cm long, soon shrivelling; first 2 leaves opposite.

Other botanical information

Trees may start flowering when only 5 m tall. Flowering and fruiting occur throughout the year. The seeds are eaten by chimpanzees, which in some regions open the hard fruit stones using stone tools, and by red river hogs. Probably rodents serve as seed dispersers, but elephants have also been suggested to play an important role in dispersal of seeds and regeneration.

Maranthes comprises 12 species, of which 10 occur in tropical Africa and one each in tropical Asia and tropical America.

Maranthes glabra has been confused with Maranthes robusta (Oliv.) Prance.

Ecology

Maranthes glabra occurs in evergreen and semi-deciduous forest, mostly on dry land but occasionally in temporarily flooded localities. It occurs from sea-level up to 1000 m altitude, in eastern DR Congo up to 1900 m. In Ghana it has been reported to be strongly associated with acidic, base-poor soils.

Management

There are 30–90 fruit stones per kg. The stones may take very long to germinate, from 4 months to 3 years, and the germination rate is low.

Natural regeneration seems to be fair but periodic as often most trees found in a forest are of the same age. Maranthes glabra has been classified as a shade bearer. In general, it occurs scattered in the forest or in small groups. Logs sink in water and cannot not be transported by river.

Genetic resources

Maranthes glabra is widespread and not heavily exploited. It is unlikely to be under threat of genetic erosion, except where its habitat is being destructed.

Prospects

The wood of Maranthes glabra will remain locally important for purposes for which it can be processed green, such as for beams and posts for construction, canoes and railway sleepers. It will also remain an important source of firewood.

Major references

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., 1985. The useful plants of West Tropical Africa. 2nd Edition. Volume 1, Families A–D. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 960 pp.

Letouzey, R. & White, F., 1978. Chrysobalanaceae. Flore du Cameroun. Volume 20. Muséum National d’Histoire Naturelle, Paris, France. pp. 3–138.

Prance, G.T. & Sothers, C.A., 2003. Chrysobalanaceae 2: Acioa to Magnistipula. Species Plantarum: Flora of the World. Part 10. Australian Biological Resources Study, Canberra, Australia. 268 pp.

Takahashi, A., 1978. Compilation of data on the mechanical properties of foreign woods (part 3) Africa. Shimane University, Matsue, Japan. 248 pp.

Other references

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.

Keay, R.W.J., 1989. Trees of Nigeria. A revised version of Nigerian trees (1960, 1964) by Keay, R.W.J., Onochie, C.F.A. & Stanfield, D.P. Clarendon Press, Oxford, United Kingdom. 476 pp.

Letouzey, R. & White, F., 1978. Chrysobalanacées. Flore du Gabon. Volume 24. Muséum National d’Histoire Naturelle, Paris, France. pp. 3–138.

Neuwinger, H.D., 2000. African traditional medicine: a dictionary of plant use and applications. Medpharm Scientific, Stuttgart, Germany. 589 pp.

Poorter, L., Bongers, F., Kouamé, F.Y.N. & Hawthorne, W.D., 2004. Biodiversity of West African forests: an ecological atlas of woody plant species. CABI, Wallingford, United Kingdom. 521 pp.

Raponda-Walker, A. & Sillans, R., 1961. Les plantes utiles du Gabon. Paul Lechevalier, Paris, France. 614 pp.

Savill, P.S. & Fox, J.E.D., 1967. Trees of Sierra Leone. Forest Department, Freetown, Sierra Leone. 316 pp.

Vivien, J. & Faure, J.J., 1985. Arbres des forêts denses d’Afrique Centrale. Agence de Coopération Culturelle et Technique, Paris, France. 565 pp.

White, F., 1976. The taxonomy, ecology and chorology of African Chrysobalanaceae (excluding Acioa). Bulletin du Jardin botanique national de Belgique 46(3–4): 265–350.

White, L. & Abernethy, K., 1997. A guide to the vegetation of the Lopé Reserve, Gabon. 2nd edition. Wildlife Conservation Society, New York, United States. 224 pp.

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. Maranthes glabra (Oliv.) Prance. 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.