Scottellia klaineana (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Medicinal
Timber

Scottellia klaineana Pierre

Protologue: Bull. Mens. Soc. Linn. Paris, ser. 2, 14: 113 (1899).

Family: Flacourtiaceae (APG: Achariaceae)

Synonyms

Scottellia kamerunensis Gilg (1908), Scottellia chevalieri Chipp (1923), Scottellia coriacea A.Chev. ex Hutch. & Dalziel (1927).

Vernacular names

Akossika (Fr).

Origin and geographic distribution

Scottellia klaineana occurs from Sierra Leone east to the Central African Republic and south to DR Congo and northern Angola.

Uses

The wood of Scottellia klaineana, traded as ‘akossika’ or ‘odoko’, is used for posts in house building, light flooring, joinery, interior trim, ladders, sporting goods, toys, novelties, food containers, spoons, ladles, combs, tool handles, draining boards, carving and turnery. It is suitable for furniture, cabinet making, veneer and plywood. It is also used as firewood.

Roots and bark are used in traditional medicine. Root decoctions are taken as diuretic and purgative, and to treat oedema, and bark decoctions to treat stomach-ache. In Nigeria, the wood ash is used by the Yoruba people in soap making.

Production and international trade

The export of ‘akossika’ wood from Côte d’Ivoire was 58,000 m³ in 2004, 28,000 m³ in 2005 and 16,000 m³ in 2006.

Properties

The heartwood is pale yellow to pale yellowish brown, occasionally with darker streaks, and indistinctly demarcated from the up to 10 cm wide sapwood. The grain is usually straight, sometimes interlocked, texture usually fine. Quarter-sawn surfaces show an attractive silver grain figure. The wood is fairly lustrous, odourless and tasteless when dried.

The wood is medium-weight, with a density of 590–750 kg/m³ at 12% moisture content, moderately hard and tough. It air and kiln dries satisfactorily, but is liable to checking, splitting and warping, especially in thick boards. The rates of shrinkage are moderately high, from green to oven dry 4.1–5.4% radial and 9.2–11.6% tangential. During drying, the wood is susceptible to blue stain attack. Once dry, it is moderately stable in service.

At 12% moisture content, the modulus of rupture is 82–140 N/mm², modulus of elasticity 8000–14,700 N/mm², compression parallel to grain 45–70 N/mm², shear 8–15 N/mm², cleavage 17–25 N/mm, Janka side hardness 4840–7480 N, Janka end hardness 7200–8110 N and Chalais-Meudon side hardness 2.5–4.3.

The wood saws and works well with both machine and hand tools. It takes a good finish and polishes well. It is slightly brittle and quarter-sawn surfaces tend to flake. It has a tendency to split upon nailing; pre-boring is advised. It has good screw-holding properties. The wood paints and varnishes easily. The gluing properties are good. Slicing and peeling should be done with care because the veneer has a tendency to break across. The wood is not durable, being liable to fungal, termite, pinhole borers, Lyctus and marine borer attacks. It is permeable to impregnation with preservatives.

Description

Evergreen, medium-sized tree up to 30(–35) m tall; bole branchless for up to 20 m, usually straight, up to 100(–130) cm in diameter, slightly fluted at base or with small buttresses; bark surface fairly smooth to slightly scaly, greenish grey to dark brown, inner bark thin, granular, orange brown to reddish brown, rapidly darkening to brown upon exposure, with colourless exudate and almond-like smell; crown often small, narrow and dense; twigs glabrous, with lenticels. Leaves alternate, simple; stipules absent; petiole 0.5–1(–2) cm long, rather slender; blade obovate to obovate-oblong or elliptical, 5–16 cm × 3–9 cm, broadly cuneate at base, usually acuminate at apex, margins entire to wavy or shallowly toothed, leathery, glabrous, pinnately veined with 5–8 pairs of lateral veins. Inflorescence an axillary raceme 4–10 cm long, slightly hairy. Flowers bisexual or male, regular, 5-merous, creamy white, scented; pedicel 3–5(–8) mm long; sepals free, rounded to elliptical, 3–4 mm long; petals oblong-obovate, (4–)5 mm long, hairy at margins, at the base inside with a scale-like hairy appendage; stamens alternating with petals, 3–5 mm long; ovary superior, glabrous, 1-celled, style short, 3-lobed at apex. Fruit a nearly globose capsule (3–)4–8(–9) mm in diameter, finely warty, dehiscing with 3 valves, 1–2(–3)-seeded. Seeds globose-angular, up to 5 mm in diameter, smooth, covered by a thin orange-red aril. Seedling with epigeal germination; hypocotyl 4–5 cm long, epicotyl 0.5–1 cm long, hairy; cotyledons leafy, rounded, 1–2 cm long; first leaves alternate.

Other botanical information

Scottellia comprises 3 species and is restricted to West and Central Africa. It seems to be related to Dasylepis, Erythrospermum and Rawsonia.

Scottellia leonensis

Scottellia leonensis Oliv., a small to medium-sized tree up to 20 m tall with bole up to 30 cm in diameter, occurring in coastal swamp forest and gallery forest from Guinea Bissau east to Liberia, differs from Scottellia klaineana in its thicker and often larger leaves with thicker petioles. Its wood is possibly used for similar purposes.

Scottellia orientalis

Scottellia orientalis Gilg, a medium-sized to fairly large tree up to 40 m tall with bole diameter up to 100 cm, occurring from Nigeria east to southern Sudan and south to DR Congo, is difficult to distinguish from Scottellia klaineana, except by its larger fruits. Its wood is probably used for similar purposes.

Scottellia klaineana is variable, with 2 varieties being distinguished, connected by transitions.

Anatomy

Wood-anatomical description (IAWA hardwood codes):

• Growth rings: 2: growth ring boundaries indistinct or absent.
• Vessels: 5: wood diffuse-porous; (12: solitary vessel outline angular); 14: scalariform perforation plates; 15: scalariform perforation plates with ≤ 10 bars; (16: scalariform perforation plates with 10–20 bars); 22: intervessel pits alternate; 23: shape of alternate pits polygonal; 26: intervessel pits medium (7–10 μm); 27: intervessel pits large (≥ 10 μm); 31: vessel-ray pits with much reduced borders to apparently simple: pits rounded or angular; 41: mean tangential diameter of vessel lumina 50–100 μm; 42: mean tangential diameter of vessel lumina 100–200 μm; 47: 5–20 vessels per square millimetre; 48: 20–40 vessels per square millimetre.
• Tracheids and fibres: 61: fibres with simple to minutely bordered pits; 62: fibres with distinctly bordered pits; 65: septate fibres present; 66: non-septate fibres present; 69: fibres thin- to thick-walled.
• Axial parenchyma: 75: axial parenchyma absent or extremely rare.
• Rays: 98: larger rays commonly 4- to 10-seriate; 102: ray height > 1 mm; 103: rays of two distinct sizes; 107: body ray cells procumbent with mostly 2–4 rows of upright and/or square marginal cells; 108: body ray cells procumbent with over 4 rows of upright and/or square marginal cells; 110: sheath cells present; 115: 4–12 rays per mm.
• Mineral inclusions: 136: prismatic crystals present; 137: prismatic crystals in upright and/or square ray cells; (140: prismatic crystals in chambered upright and/or square ray cells); (159: silica bodies present); (160: silica bodies in ray cells).

(L.Awoyemi, P.E. Gasson & E.A. Wheeler)

Growth and development

The growth is slow. In Côte d’Ivoire an investigation of growth rings showed a mean annual bole diameter growth of 4.5 mm for the first 30 years, 6 mm for trees of 30–80 years old and 5 mm for trees of 80–140 years old. In field trials the mean annual diameter growth was only 2–3 mm.

Although Scottellia klaineana is usually evergreen, it is reported to be deciduous for up to 2 months (October–November) in Sierra Leone. In West Africa, flowering has been recorded in February–August and fruits ripen in May–December. In Gabon trees flower in December–January and have ripe fruits in January–April. The seeds with their red arils are probably dispersed by birds, but monkeys also eat the arils.

Ecology

Scottellia klaineana most commonly occurs in lowland evergreen forest, but can also be found in semi-deciduous forest. It often occurs in small stands along rivers and streams, but may also be common in rocky localities. It is sensitive to forest fires.

Propagation and planting

There are about 25,000 seeds per kg. Although seedlings are often common in the understorey close to mother trees, the germination rate of seed has been reported to be low, only 15–25% 8–12 days after sowing. Saplings and young trees are fairly shade tolerant, but older trees are reported to be light demanding. Regeneration is commonly observed in undisturbed forest.

Management

Scottellia klaineana usually occurs scattered in the forest or in small groups of trees. In forest in western Cameroon, a mean density of 0.15 tree with a bole diameter above 60 cm has been recorded per ha, with an average wood volume of 0.9 m³/ha. In Côte d’Ivoire 7–27 trees with a bole diameter of more than 10 cm have been recorded per ha. Moderate thinning resulted in better growth of young trees.

Handling after harvest

After harvest, logs should be removed rapidly from the forest or treated with preservatives because the wood is susceptible to blue stain attack. Fresh logs float in water and can thus be transported by river.

Genetic resources

Scottellia klaineana is locally common and in most regions within its distribution area there are no indications of overexploitation. Therefore it is unlikely to be liable to genetic erosion. However, in some regions, e.g. in Côte d’Ivoire, exploitation seems to be considerable and may cause serious pressure on populations of the species.

Prospects

Presently, Scottellia klaineana has limited importance on the international timber market, but its multipurpose wood may have good prospects for further commercialization. However, information on available stands, growth rates, silviculture and propagation is very limited and much research is still needed to be able to develop sustainable management systems for this poorly known species.

Major references

• ATIBT (Association Technique Internationale des Bois Tropicaux), 1986. Tropical timber atlas: Part 1 – Africa. ATIBT, Paris, France. 208 pp.

• 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.

• CIRAD Forestry Department, 2009. Akossika. [Internet] Tropix 6.0. http://tropix.cirad.fr/ africa/akossika.pdf. January 2010.

• Cooper, G.P. & Record, S.J., 1931. The evergreen forests of Liberia. School of Forestry, Yale University, Bulletin 31, New Haven, United States. 153 pp.

• Guiscafre, J., 1977. Akossika (Scottellia sp.). Bois et Forêts des Tropiques 172: 27–31.

• 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.

• Oteng-Amoako, A.A. (Editor), 2006. 100 tropical African timber trees from Ghana: tree description and wood identification with notes on distribution, ecology, silviculture, ethnobotany and wood uses. 304 pp.

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

• Sleumer, H., 1972. A taxonomic revision of the genus Scottellia Oliv. (Flacourtiaceae). Blumea 20(2): 275–281.

Other references

• Aubréville, A., 1959. La flore forestière de la Côte d’Ivoire. Deuxième édition révisée. Tome troisième. Publication No 15. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 334 pp.

• Bamps, P., 1968. Flacourtiaceae. In: Flore du Congo, du Ruanda et du Burundi. Spermatophytes. Jardin botanique national de Belgique, Brussels, Belgium. 61 pp.

• Bertault, J.-G., Miézan, K., Dupuy, B., Durrieu de Madron, L. & Amsallem, I., 1999. Croissance et productivité en forêt dense humide après incendie: le dispositif de la Téné, Côte d’Ivoire (1978–1993). Document Forafri 20. Cirad-Forêt, Montpellier, France. 67pp.

• Blackett, H. & Gardette, E., 2008. Cross-border flows of timber and wood products in West Africa. Final Report. European Commission, Brussels, Belgium. 109 pp.

• Chase, M.W., Zmarzty, S., Lledo, M.D., Wurdack, K.J., Swensen, S.M. & Fay, M.F., 2002. When in doubt, put it in Flacourtiaceae: a molecular phylogenetic analysis based on plastid rbcL DNA sequences. Kew Bulletin 57(1): 141–181.

• de la Mensbruge, G., 1966. La germination et les plantules des essences arborées de la forêt dense humide de la Côte d’Ivoire. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 389 pp.

• Détienne, P., 1974. Essai de determination de l’âge de l’Akossika, Scottellia chevalieri Chipp. par les cernes du bois. Centre technique forestier tropical, Nogent-sur-Marne, France. 8 pp.

• Hawthorne, W.D. & Gyakari, N., 2006. Photoguide for the forest trees of Ghana: a tree-spotter’s field guide for identifying the largest trees. Oxford Forestry Institute, Department of Plant Sciences, Oxford, United Kingdom. 432 pp.

• Hul, S., 1995. Flacourtiaceae. Flore du Gabon. Volume 34. Muséum National d’Histoire Naturelle, Paris, France. 82 pp.

• Irvine, F.R., 1961. Woody plants of Ghana, with special reference to their uses. Oxford University Press, London, United Kingdom. 868 pp.

• Keay, R.W.J., 1954. Flacourtiaceae. In: Keay, R.W.J. (Editor). Flora of West Tropical Africa. Volume 1, part 1. 2nd Edition. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. pp. 185–190.

• 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.

• 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.

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

• Sallenave, P., 1955. Propriétés physiques et mécaniques des bois tropicaux de l’Union française. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 129 pp.

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

• Wilks, C. & Issembé, Y., 2000. Les arbres de la Guinée Equatoriale: Guide pratique d’identification: région continentale. Projet CUREF, Bata, Guinée Equatoriale. 546 pp.

Sources of illustration

• Aubréville, A., 1959. La flore forestière de la Côte d’Ivoire. Deuxième édition révisée. Tome troisième. Publication No 15. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 334 pp.

• Hul, S., 1995. Flacourtiaceae. Flore du Gabon. Volume 34. Muséum National d’Histoire Naturelle, Paris, France. 82 pp.

• Wilks, C. & Issembé, Y., 2000. Les arbres de la Guinée Equatoriale: Guide pratique d’identification: région continentale. Projet CUREF, Bata, Guinée Equatoriale. 546 pp.

Author(s)

• A. Addo-Danso, Forestry Research Institute of Ghana (FORIG), University P.O. Box 63, KNUST, Kumasi, Ghana

Correct citation of this article

Addo-Danso, A., 2012. Scottellia klaineana Pierre. 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 23 April 2026.

• See the Prota4U database.