Prota 7(1): Timbers/Bois d’œuvre 1
Trans. Linn. Soc. London 27: 18 (1869).
Sterculiaceae (APG: Malvaceae)
Octolobus angustatus Hutch. (1937).
Origin and geographic distribution
Octolobus spectabilis is distributed from Sierra Leone to DR Congo and Angola; also in Tanzania.
In Nigeria the stems of Octolobus spectabilis are made into spear shafts. The seeds are said to be edible. A maceration of the root bark is taken against sexual asthenia.
The wood of Octolobus spectabilis is yellowish white, with brownish necrosis in the centre. The texture is fine. The wood is heavy and rather hard.
Shrub or small tree up to 10(–15) m tall; bole up to 15 cm in diameter; branchlets densely stellate-hairy but glabrescent. Leaves alternate, simple and entire; stipules attenuate, 4–12 mm long, usually less than 1 mm wide; petiole up to 7 cm long, pubescent, rusty brown; blade obovate-elliptical to obovate-oblong, 6–24(–30) cm × 1.5–8(–11) cm, base cuneate to rounded, apex acuminate, papery, light brown, with (5–)7–11 pairs of lateral veins. Flowers solitary, male or bisexual, yellow, sessile, surrounded at base by an involucre of 7–20 ovate bracts; calyx 8-lobed, 1.5–3.5 cm long, with tube c. 1.5 cm long and oblong-lanceolate lobes 1–1.5 cm long, with crisp marginal fringes, hairy outside; corolla absent; male flowers with an androphore 5–7 mm long, carrying a whorl of numerous connate stamens c. 4 mm long; bisexual flowers with numerous carpels in 2–4 imbricate rows. Fruit consisting of 10–65 follicles; follicles almost globose, up to 5 cm × 3.5 cm, with stipe 0.5–1.5 cm long and pointed beak 2–5 mm long, scabrous, densely and shortly hairy, reddish brown, 2–7-seeded. Seeds compressed, plano-convex, diameter c. 15 mm, black, shiny, surrounded by mucilage. Seedling with epigeal germination.
Octolobus comprises 3–4 species. It is closely related to Cola , but differs in its 8-lobed calyx and numerous carpels. Octolobus spectabilis is highly variable.
In Ghana Octolobus spectabilis flowers in January–February; fruiting is in February.
In West Africa Octolobus spectabilis occurs in the undergrowth of forest, scattered but common in dry forest types. In Central Africa its habitats are dense humid semi-deciduous forest and gallery forest. In Tanzania Octolobus spectabilis is found in forest at round 1000 m altitude.
Genetic resources and breeding
In view of its wide distribution and common occurrence, e.g. in Nigeria, Octolobus spectabilis is not threatened by genetic erosion.
Little is known on the timber properties of Octolobus spectabilis, but its small size and bole diameter are serious limitations to its use.
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Correct citation of this article:
Brink, M., 2007. Octolobus spectabilis Welw. In: Louppe, D., Oteng-Amoako, A.A. & Brink, M. (Editors). Prota 7(1): Timbers/Bois d’œuvre 1. [CD-Rom]. PROTA, Wageningen, Netherlands.