Sterculia africana (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Cereal / pulse
Fruit
Vegetable
Vegetable oil
Carbohydrate / starch
Essential oil / exudate
Medicinal
Timber
Ornamental
Forage / feed
Auxiliary plant
Fibre
Food security

Sterculia africana (Lour.) Fiori

Protologue: Agric. Colon. 5, suppl.: 37 (1912).

Family: Sterculiaceae (APG: Malvaceae)

Chromosome number: 2n = 36

Synonyms

• Triphaca africana Lour. (1790),
• Sterculia triphaca R.Br. (1844),
• Sterculia guerichii K.Schum. (1894).

Vernacular names

• African star-chestnut, tick tree, false baobab (En).
• Mgoza, mdoza, ngoro (Sw).

Origin and geographic distribution

Sterculia africana is distributed throughout East and southern Africa, except for Kenya and Uganda.

Uses

The bark fibre is used for making mats, string and rope, and for tying in house construction. The wood is used for poles in house construction, for instance for making frameworks of movable houses of pastoralists, with the bark being used for tying the wood together. It is the preferred wood of the Damara people in Namibia for carving winnowing bowls. The wood is also used for making furniture, for fencing and as fuelwood. In Namibia the bark is burnt for its aroma. The tree produces a gum, which is used as additive to medicines, but the quantities are too small for commercial exploitation. The gum, which resembles gum tragacanth from Astralagus spp., was formerly used for making gun powder for muzzle-loading guns. In Malawi the fresh leaves are cooked in sauces with Moringa and/or okra. In Ethiopia the leaves are browsed by cattle, goats and sheep. The pods are used as amulets and snuff boxes. The ash of burnt fruits is used as a cooking soda, especially for cooking vegetables. Hairs from the fruit have been added to snuff to improve the flavour. The roasted seeds are eaten. In Malawi they are pounded into an oily paste before being eaten. The flour of roasted and pounded seeds is cooked and eaten with vegetables. Oil is extracted from roasted seeds. The dry seeds are used as beads. Sterculia africana is grown as a living fence and is a bee forage.

Sterculia africana is widely used in African traditional medicine. In Somalia a decoction of the crushed fresh roots is drunk as an anthelmintic. In Tanzania a root decoction is taken against back pain, hernia and dizziness, a root infusion is drunk as an aphrodisiac, and leaf decoctions are drunk against fungal infections and convulsions. In East Africa the roots, bark and leaves are boiled and the vapour inhaled for the treatment of influenza and fever. In Namibia a root or bark decoction is drunk by women for the treatment of postnatal and stomach pains, a leaf infusion is drunk against cough and chest complaints, and a fruit decoction is drunk to relieve pain during pregnancy and after giving birth. In Malawi the irritant hairs along the splitting point of the fruits are recorded to be burnt and the ash used as an ointment for the treatment of eye infections, especially in babies.

Properties

The wood is pinkish or greyish, with the heartwood not distinctly demarcated from the sapwood. The wood is soft and very lightweight.

Dried leaves are more palatable for cattle and goats than green leaves. Dried foliage (dry matter content 88.7%) collected in Ethiopia in the wet season contained per 100 g dry matter: crude protein 12.7 g, hydrolysable tannins 14.2 g, neutral detergent fibre 35.7 g, acid detergent fibre 26.4 g and acid detergent lignin 6.9 g. The in-vitro dry matter digestibility was 78%. In the dry season the dried foliage (dry matter content 91.9%) contained per 100 g dry matter: crude protein 14.7 g, hydrolysable tannins 12.2 g, neutral detergent fibre 42.3 g, acid detergent fibre 21.1 g and acid detergent lignin 5.3 g, with an in-vitro dry matter digestibility of 84%. The in-sacco potential dry matter digestibility of the leaves was 93% in the wet season and 94% in the dry season, and the in-sacco potential nitrogen digestibility 90 and 91 g per kg dry matter for the wet and the dry season, respectively.

Methanol leaf extracts showed in-vitro antifungal activity against Candida krusei, Candida parapsilosis, Candida tropicalis, and Cryptococcus neoformans, but not against Candida albicans and Candida glabrata. In various assays these extracts also showed cytotoxic and genotoxic effects, and interaction potential with antiretroviral agents.

The fruits have irritating hairs. Seeds in Botswana contained per 100 g dry matter: crude protein 35.6 g, crude fat 22.8 g, tannins 3.5 g, neutral detergent fibre 15.4 g, acid detergent fibre 19.0 g, Ca 130 mg, Mg 250 mg and P 260 mg. The in-vitro true dry matter digestibility was 96%. Seeds in Botswana and Zimbabwe yielded about 32% oil, mainly composed of palmitic acid 17–20%, stearic acid 3–6%, oleic acid 17–21% and linoleic acid 26–27%. The oil contains up to 34% cyclopropenoid fatty acids known to cause physiological disorders in higher animals, and therefore it may not be recommended for food uses. The seed oil also contains β-sitosterol, stigmasterol, campesterol and γ -tocotrienol.

Description

Deciduous, monoecious, small to medium-sized tree up to 12(–25) m tall; bole up to 250 cm in diameter; bark surface whitish grey or liver-coloured, peeling in papery flakes, inner bark green; crown rounded; branches spreading; young branches hairy. Leaves alternate, crowded at the ends of branches, simple; stipules early caducous; petiole up to 10(–12.5) cm long, with greyish stellate hairs; blade orbicular or ovate-cordate in outline, 3–5(–7)-lobed or entire, 3.5–15 cm × (3–)4–13 cm, lateral lobes separated by sinuses 0.5(–2) cm deep, the sinuses of the apical lobe being always deeper, base cordate, apex rounded to acuminate, both surfaces shortly and thinly stellate-hairy to glabrescent, c. 7-veined from the base. Inflorescence borne on leafless branch apices, 2–6(–20) per branch, spike-like or with 2–5 branches, up to 12 cm long, hairy. Flowers unisexual, regular, 5-merous, 7–8 mm long, up to 2.5 cm in diameter, greenish to yellowish with pink or red markings; pedicel up to 10 mm long, perianth campanulate with 5 lobes 7–9 mm × 4–4.5 mm, stellate hairy; male flowers with c. 10 anthers borne on a long common stalk; female flowers with superior ovary consisting of 5 loosely united carpels. Fruit consisting of 1–5 ellipsoid or oblong-ovoid follicles 4–15 cm long, each splitting down one side, beaked, tomentose to subscabrid, yellowish brown, suture fringed with irritating hairs 2–3 mm long, many-seeded. Seeds ellipsoid-oblong, 9–15 mm × 5–8 mm, grey-black, tick-like, with apical aril 2–3 mm × 3–5 mm, aril drying white.

Other botanical information

Sterculia comprises about 150 species and occurs throughout the tropics. In tropical Africa about 25 species can be found. The bark fibre of various Sterculia species is locally used like that of Sterculia africana.

Sterculia mhosya Engl. is a shrub or small tree up to 10 m tall, distributed in Tanzania and Zambia. Its bole is used for making canoes, its bark for making rope, its leaves as toilet paper and its seeds are eaten like groundnuts. A bark decoction is drunk against indigestion.

Sterculia rhynchocarpa K.Schum., a shrub or small tree up to 9(–15) m tall, distributed in Ethiopia, Somalia, Kenya and Tanzania, is very closely related to Sterculia africana and has been misidentified as Sterculia africana in Kenya. Its bark yields material for tying and its seeds are eaten. Leaf litter is eaten by goats and cattle. A decoction of the root and bark is drunk and used to wash the body for the treatment of malaria, and a bark decoction is drunk in case of stomach complaints. Sterculia rhynchocarpa is a host of the cotton pests Dysdercus cardinalis and Dysdercus fasciatus.

Sterculia rogersii N.E.Br. (common star-chestnut, small-leaved star-chestnut) is a shrub or small tree up to 8 m tall distributed in Botswana, Zimbabwe, Mozambique, Swaziland and South Africa. It yields a bark fibre of good quality used for tying in hut-building, for making fishing lines and nets, and as a thread for sewing sleeping mats and grain baskets. The seeds are eaten as a famine food, and livestock eats the seeds and aerial parts. The wood is soft and brittle, and the heartwood is recorded to have been eaten in times of famine.

Sterculia stenocarpa Winkler is a shrub or small tree up to 15 m tall, distributed in Sudan, Ethiopia, Somalia, Kenya, Uganda and Tanzania. Its bark is used for making tough and durable string and rope. Its twigs are used for cleaning milk containers in Kenya. Its fruit and seeds are edible. In traditional medicine in Kenya the root is boiled with butter in water and used for the treatment of indigestion in newborn babies and malaria in children. In Tanzania the leaves are pounded with water and squeezed, and the juice is applied on leprous sores, while the fresh bark enters in preparations taken for the treatment of abdominal pains accompanied by mild bleeding from the vagina.

Growth and development

At 28 months after planting the average height of Sterculia africana planted at Chalimbana (Zambia) was 1.1 m, with an average stem diameter of 6.1 cm. Flowers generally appear before the new foliage. In southern Africa flowering is usually in September–December, and fruiting in January–June.

Ecology

Sterculia africana occurs in hot, dry areas from sea-level up to 1800 m altitude in woodland, bushland or grassland, often on rocky slopes or outcrops.

Propagation and planting

Seeds and cuttings can be used for propagation. The 1000-seed weight is 35–190 g. A germination rate of 65% after 20 days has been reported. Seeds retain viability for 2 months at room temperature.

Management

Sterculia africana is mostly exploited from natural stands, but it is also planted and tended. The tree can be pruned and coppiced.

Diseases and pests

Sterculia africana is a host of the cotton pests Dysdercus cardinalis and Dysdercus fasciatus.

Genetic resources

In view of its wide distribution and range of habitats, Sterculia africana is not threatened with genetic erosion. In Namibia the species is protected by forestry legislation.

Prospects

Sterculia africana is a useful multipurpose tree, not only yielding fibre for the local production of mats and ropes, but also a range of other products, including edible leaves and seeds. Oil extraction from its seeds has technically been demonstrated to be feasible and may have commercial potential. The seed oil is not safe for human consumption, but could be used for cosmetic purposes and bio-fuel. The irritating hairs on the fruit and the fact that it is host of cotton stainers may limit the potential of Sterculia africana.

Major references

• Bekele-Tesemma, A., 2007. Useful trees and shrubs for Ethiopia: identification, propagation and management for 17 agroclimatic zones. Technical Manual No 6. RELMA in ICRAF Project, Nairobi, Kenya. 552 pp.

• Cheek, M. & Dorr, L., 2007. Sterculiaceae. In: Beentje, H.J. & Ghazanfar, S.A. (Editors). Flora of Tropical East Africa. Royal Botanic Gardens, Kew, Richmond, United Kingdom. 134 pp.

• Coates Palgrave, K., 1983. Trees of southern Africa. 2nd Edition. Struik Publishers, Cape Town, South Africa. 959 pp.

• Hamza, O.J.M., van den Bout-van den Beukel, C.J.P., Matee, M.I.N., Moshi, M.J., Mikx, F.H.M., Selemani, H.O., Mbwambo, Z.H., van der Ven, A.J.A.M. & Verweij, P.E., 2006. Antifungal activity of some Tanzanian plants used traditionally for the treatment of fungal infections. Journal of Ethnopharmacology 108(1): 124–132.

• Melaku, S., Aregawi, T. & Nigatu, L., 2010. Chemical composition, in vitro dry matter digestibility and in sacco degradability of selected browse species used as animal feeds under semi-arid conditions in northern Ethiopia. Agroforestry Systems 80(2): 173–184.

• Mitei, Y.C., Ngila, J.C., Yeboah, S.O., Wessjohann, L. & Schmidt, J., 2009. NMR, GC-MS and ESI-FTICR-MS profiling of fatty acids and triacylglycerols in some Botswana seed oils. Journal of the American Oil Chemists’ Society 85(11): 1021–1032.

• Palmer, E. & Pitman, N., 1972–1974. Trees of southern Africa, covering all known indigenous species in the Republic of South Africa, South-West Africa, Botswana, Lesotho and Swaziland. 3 volumes. Balkema, Cape Town, South Africa. 2235 pp.

• SEPASAL, 2010. Sterculia africana. [Internet] Survey of Economic Plants for Arid and Semi-Arid Lands (SEPASAL) database. Royal Botanic Gardens, Kew, Richmond, United Kingdom. http://www.kew.org/ ceb/sepasal/. November 2010.

• Thulin, M., 1999. Sterculiaceae. In: Thulin, M. (Editor). Flora of Somalia. Volume 2. Angiospermae (Tiliaceae-Apiaceae). Royal Botanic Gardens, Kew, Richmond, United Kingdom. pp. 21–37.

• van den Bout van den Beukel, C.J., Hamza, O.J., Moshi, M.J., Matee, M.I., Mikx, F., Burger, D.M., Koopmans, P.P., Verweij, P.E., Schoonen, W.G. & van der Ven, A.J., 2008. Evaluation of cytotoxic, genotoxic and CYP450 enzymatic competition effects of Tanzanian plant extracts traditionally used for treatment of fungal infections. Basic & Clinical Pharmacology & Toxicology 102(6): 515–526.

Other references

• Aganga, A.A., Adogla-Bessa, T., Omphile, U.J. & Tshireletso, K., 2000. Significance of browses in the nutrition of Tswana goats. Archivos de Zootecnia 49(188): 469–480.

• Aregawi, T., Melaku, S. & Nigatu, L., 2008. Management and utilization of browse species as livestock feed in semi-arid district of North Ethiopia. [Internet] Livestock Research for Rural Development 20(6), article 86. 8 pp. http://www.lrrd.org/ lrrd20/6/ areg20086.htm. November 2010.

• Beentje, H.J., 1994. Kenya trees, shrubs and lianas. National Museums of Kenya, Nairobi, Kenya. 722 pp.

• Bein, E., Habte, B., Jaber, A., Birnie, A. & Tengnäs, B., 1996. Useful trees and shrubs in Eritrea: identification, propagation and management for agricultural and pastoral communities. Technical Handbook No 12. Regional Soil Conservation Unit, Nairobi, Kenya. 422 pp.

• Booth, F.E.M. & Wickens, G.E., 1988. Non-timber uses of selected arid zone trees and shrubs in Africa. FAO Conservation Guide No 19. FAO, Rome, Italy. 176 pp.

• Chikuni, A.C., 1994. Conservation status of mopane woodlands in Malawi: a case study of Mua Tsanya Forest Reserve. In: van der Maesen, L.J.G., van der Burgt, X.M. & van Medenbach de Rooy, J.M. (Editors). The biodiversity of African plants. Proceedings of the 14th AETFAT Congress, 22–27 August 1994, Wageningen, Netherlands. Kluwer Academic Publishers, Dordrecht, Netherlands. pp. 250–258.

• Cornelius, J.A., Hammonds, T.W., Leicester, J.B., Ndabahweji, J.K., Rosie, D.A. & Shone, G.G., 1970. New tropical seed oils. 3. Component acids of leguminous and other seed oils (continued). Journal of the Science of Food and Agriculture 21(1): 49–50.

• Dharani, N., 2002. Field guide to common trees and shrubs of East Africa. Struik Publishers, Cape Town, South Africa. 320 pp.

• Hedberg, I., Hedberg, O., Madati, P.J., Mshigeni, K.E., Mshiu, E.N. & Samuelsson, G., 1983. Inventory of plants used in traditional medicine in Tanzania. Part III. Plants of the families Papilionaceae-Vitaceae. Journal of Ethnopharmacology 9: 237–260.

• Ichikawa, M., 1987. A preliminary report on the ethnobotany of the Suiei Dorobo in northern Kenya. African Study Monographs, Supplement 7: 1–52.

• Kamara, C.S. & Maghembe, J.A., 1994. Performance of multipurpose tree and shrub species 28 months after planting at Chalimbana, Zambia. Forest Ecology and Management 64(2–3): 145–151.

• Mbuya, L.P., Msanga, H.P., Ruffo, C.K., Birnie, A. & Tengnäs, B., 1994. Useful trees and shrubs for Tanzania: identification, propagation and management for agricultural and pastoral communities. Technical Handbook 6. Regional Soil Conservation Unit/SIDA, Nairobi, Kenya. 542 pp.

• Mitei, Y.C., Ngila, J.C., Yeboah, S.O., Wessjohann, L. & Schmidt, J., 2008. Profiling of phytosterols, tocopherols and tocotrienols in selected seed oils from Botswana by GC-MS and HPLC. Journal of the American Oil Chemists’ Society 86: 617–625.

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

• Pratt, J.H., Henry, E.M.T., Mbeza, H.F., Mlaka E. & Satali, L.B., 2002. Malawi Agroforestry Extension Project Marketing & Enterprise Program. Main Report. Publication No. 47. Malawi Agroforestry Extension Project (MAFE), Lilongwe, Malawi. 119 pp.

• Ruffo, C.K., Birnie, A. & Tengnäs, B., 2002. Edible wild plants of Tanzania. Technical Handbook No 27. Regional Land Management Unit/ SIDA, Nairobi, Kenya. 766 pp.

• Schmidt, E., Lötter, M. & McCleland, W., 2002. Trees and shrubs of Mpumalanga and Kruger National Park. Jacana Publishers, Johannesburg, South Africa. 702 pp.

• Van den Eynden, V., Vernemmen, P. & Van Damme, P., 1992. The ethnobotany of the Topnaar. University of Gent, Belgium. 145 pp.

• van Wyk, B. & van Wyk, P., 1997. Field guide to trees of southern Africa. Struik Publishers, Cape Town, South Africa. 536 pp.

• Williamson, J., 1955. Useful plants of Nyasaland. The Government Printer, Zomba, Nyasaland. 168 pp.

Sources of illustration

• Thulin, M., 1999. Sterculiaceae. In: Thulin, M. (Editor). Flora of Somalia. Volume 2. Angiospermae (Tiliaceae-Apiaceae). Royal Botanic Gardens, Kew, Richmond, United Kingdom. pp. 21–37.

Author(s)

• F.W. Owusu, Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana

• N.S.A. Derkyi, CSIR-Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana

Correct citation of this article

Owusu, F.W. & Derkyi, N.S.A., 2011. Sterculia africana (Lour.) Fiori. [Internet] Record from PROTA4U. Brink, M. & Achigan-Dako, E.G. (Editors). PROTA (Plant Resources of Tropical Africa / Ressources végétales de l’Afrique tropicale), Wageningen, Netherlands. <http://www.prota4u.org/search.asp>.

Accessed 13 December 2024.

• See the Prota4U database.