Prota 7(1): Timbers/Bois d’œuvre 1
Ann. Mus. Natl. Hist. Nat. 4: 91 (1804).
Tiliaceae (APG: Malvaceae)
Grewia pubescens P.Beauv. (1819), Grewia venusta Fresen. (1837).
Origin and geographic distribution
Grewia mollis occurs widely in tropical Africa, from Senegal and Gambia eastward to Somalia and southward to Angola, Zambia and Zimbabwe; it also occurs in Yemen.
The wood of Grewia mollis is widely used, e.g. for house construction, bed frames, walking sticks, tool handles, clubs, bows and arrows, shields, spear shafts and whips. It is also used as firewood and made into charcoal.
The bark and leaves of Grewia mollis are mucilaginous and commonly used in soups; dried and ground they are mixed with bean-meal to make cakes. In DR Congo the bark is kneaded with water into a viscous substance that is added to sauces. In Gabon the inner bark is sometimes eaten. Flowers, buds and young shoots are added to soups and sauces, e.g. in Nigeria. In Sudan the young leaves are eaten cooked as a vegetable. Children suck nectar from the flowers, which are also attractive to bees. The fruit is eaten raw or boiled. The bark is made into cordage in Mali and Sudan. A bark maceration is applied to give a smooth surface to mud walls, floors and stoves. Wood ash is a salt substitute; the leaves, stems and roots also yield a kind of salt. Grewia mollis is browsed by domestic and wild animals.
Many applications of Grewia mollis in traditional medicine are known. The mucilaginous bark and leaves are applied to ulcers, cuts, sores and snakebites. Bark and root preparations are taken to treat cough. Extracts of bark and leaves are drunk to treat fever, or the fruit is eaten for this purpose. In Togo a decoction of the stem bark is drunk to treat diarrhoea, and a maceration is taken to ease childbirth. The mucilage is credited with laxative properties. An infusion of the bark is used to treat colic. In East Africa leaves pounded and mixed with water are taken against stomach problems and also given to constipated domestic animals. In Côte d’Ivoire a decoction of the leaves is used in baths and drinks against rickets in children and difficult birth. A decoction of the roots is drunk in Senegal in case of palpitation. In Central Africa sap from root-shavings is placed under the eyelid to treat sore eyes, whereas a liquid obtained by kneading the root bark in water is drunk to treat stomach-ache, colic and poisoning by certain plants. In Ghana a paste of ground roots is applied to rheumatic swellings and inflammation. In Nigeria the fruit is used as a febrifuge. Grewia mollis is frequently used in traditional rituals in Sudan and Ethiopia.
Production and international trade
The wood of Grewia mollis is not traded in the international market.
The wood of Grewia mollis is pinkish, hard and elastic.
Per 100 g dry matter the bark of Grewia mollis in Nigeria contains protein 3.7 g, fat 1.1 g, carbohydrate 45.3 g, fibre 45.3 g, Ca 3474 mg, Mg 743 mg, P 79 mg, Fe 10.4 mg and Zn 0.5 mg.
Shrub or small tree up to 10.5 m tall, often multi-stemmed; stem diameter up to 30 cm; young branches densely stellate-pubescent, turning dark grey to purple with age; outer bark black, thick, rough, flaking and deeply fissured, inner bark yellowish to brown, fibrous. Leaves alternate, simple; stipules lanceolate, 5–10 mm long, slightly hairy, caducous; petiole 4–13 mm long, greyish to reddish brown pubescent; blade elliptical to elliptical-oblong, 2–18 cm × 0.5–6.5 cm, base cuneate or broadly rounded or obliquely truncate, apex acute to slightly acuminate, margin toothed, 3-veined from the base, glabrous to sparsely minutely stellate-pubescent above, densely greyish to brownish white pubescent beneath. Inflorescence a cyme, (1–)2–6(–8) together in a leaf axil, 2–3.5 cm long, (1–)2–3-flowered; peduncle 8–35 mm long; bracts linear-lanceolate, up to 5 mm long, caducous. Flowers bisexual, regular, 5-merous, slightly scented; pedicel 3–11 mm long; sepals linear-oblong, 6–11 mm long, greyish hairy outside; petals obovate to oblong, 4–6(–8) mm × c. 2 mm, sometimes notched at the apex, bright yellow; androgynophore c. 1 mm long, glabrous, apex densely hairy; stamens numerous, 3–6 mm long; ovary superior, 1.5–2 mm long, densely hairy. Fruit a globose drupe 4–8 mm × 5–8 mm, finely whitish hairy, yellow turning black; endocarp hard, woody, rugose.
Grewia comprises about 150 species, distributed in the tropical and subtropical parts of Africa, Asia and Australia.
Germination of Grewia mollis often occurs after a bush fire followed by rains. Growth is slow. In Sudan flowering is around the end of March; in Uganda flowering is in May–August, and fruiting in August–October.
Grewia mollis occurs in areas with annual average rainfall of 600–1400 mm, from sea-level in West Africa up to 2200 m altitude in East Africa, in forest, open woodland, riverine thicket, Acacia-Combretum wooded grassland, and on anthills in seasonally flooded grassland. It grows on a range of soil types and is highly resistant to fire. Grewia mollis is often gregarious, with branch-suckering leading to the formation of thickets.
The products of Grewia mollis are normally collected from the wild. It can be propagated by seed or seedlings. The 1000-seed weight is 67 g. Seeds are collected from dried fruits fallen on the ground. Coppicing and pollarding is possible. Grewia mollis is a host of Pericladium grewiae, causing stem smut in various Grewia spp; infection frequently results in the production of witches’ brooms. In Tanzania the fruits are collected at the end of the rainy season.
Genetic resources and breeding
In view of its wide distribution, Grewia mollis is not threatened by genetic erosion.
Grewia mollis will remain useful as multipurpose plant, providing a wide range of products, including timber for local use, food, fibre, fodder and traditional medicines. The tree is small and is unlikely to become important as a source of sawn timber.
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Correct citation of this article:
Brink, M., 2007. Grewia mollis Juss. In: Louppe, D., Oteng-Amoako, A.A. & Brink, M. (Editors). Prota 7(1): Timbers/Bois d’œuvre 1. [CD-Rom]. PROTA, Wageningen, Netherlands.
1, flowering branch; 2, flower; 3, fruit.
Source: Flore analytique du Bénin
bark and slash