Erythroxylum mannii (PROTA)

Plant Resources of Tropical Africa Introduction

List of species

General importance
Geographic coverage Africa
Geographic coverage World
Medicinal
Timber
Fuel

drawing

Erythroxylum mannii Oliv.

Protologue: Fl. trop. Afr. 1: 274 (1868).

Family: Erythroxylaceae

Chromosome number: 2n = 24

Origin and geographic distribution

Erythroxylum mannii occurs from Guinea and Sierra Leone to Gabon and DR Congo.

Uses

The wood of Erythroxylum mannii, traded as ‘landa’, is used for furniture and cabinet work, although it may be made unsightly by ‘pith-flecks’, small darkened streaks or flecks on the face of boards created by the larvae of tiny flies. Logs are traditionally used to make dug-out canoes. The wood is suitable for construction, flooring, joinery, interior trim, mine props, ship building, toys, novelties, rifle butts, boxes, crates, vats, draining boards, turnery, carvings, veneer and plywood. It is a good firewood.

In Côte d’Ivoire a preparation from the bark is used in massaging to treat pleuritic chest pain. A decoction of leafy twigs is reputed to cure fever.

Production and international trade

Very small amounts of ‘landa’ are traded internationally. Cameroon exported 125 m³ as sawnwood in 2003. In Liberia the wood of Erythroxylum mannii has been classified as a second-class commercial timber.

Properties

The heartwood is pink to pale reddish brown, darkening upon exposure, and not distinctly demarcated from the up to 6 cm wide, whitish or greyish sapwood. The grain is straight to wavy or interlocked, texture fine and generally even. A figure of broken stripes or mottles is fairly common and numerous pith flecks 2.5–5 cm long may be present. The wood is medium-weight, with a density of 630–700 kg/m³ at 12% moisture content, and moderately hard. It air dries rapidly, with low risk of surface checking or degrade. The shrinkage rates are moderate, from green to oven dry 3.5–4% radial and 5.8–9.6% tangential. Once dry, the wood is moderately stable to unstable in service.

At 12% moisture content, the modulus of rupture is 91–134 N/mm², modulus of elasticity 11,270–14,010 N/mm², compression parallel to grain 51–57 N/mm², shear 7.5 N/mm², cleavage 15–19 N/mm, Janka side hardness 4580 N and Chalais-Meudon side hardness 2.1–3.3.

The wood saws and works well with hand and machine tools, and has a normal dulling effect on saw teeth and cutting edges. It planes well in spite of the presence of wavy or interlocked grain, but is sometimes brittle. It holds nails and screws well. Moulding properties are good, as well as gluing, polishing, painting and waxing properties. The wood is suitable for slicing and peeling. The heartwood is moderately durable, being somewhat susceptible to fungal attack but fairly resistant to termite attack. The heartwood is resistant to impregnation with preservatives, the sapwood moderately resistant.

The wood contains 37% cellulose, 31% lignin, 20% pentosan, 0.5% ash and 0.03% silica. The solubility is 6.9% in alcohol-benzene, 1.7% in hot water and 18.5% in a 1% NaOH solution.

Adulterations and substitutes

The wood of Erythroxylum mannii has some resemblance to that of Guarea spp.

Description

Deciduous medium-sized tree up to 25(–30) m tall; bole branchless for up to 15(–18) m, straight and cylindrical, up to 100(–140) cm in diameter, sometimes slightly fluted at base; bark surface fissured and scaly, greyish, inner bark soft, fibrous, with a pinkish layer outside and a yellowish white layer inside, quickly turning brown upon exposure; crown open and flattened, with few spreading main branches; twigs flattened, with lenticels. Leaves alternate, simple and entire, reddish when very young; stipules fused at base, triangular, c. 1 mm long, persistent; petiole 0.5–1 cm long; blade obovate to elliptical, 3–12 cm × 1.5–4.5 cm, base cuneate, apex rounded or slightly notched, papery, glabrous, pinnately veined with up to 20 pairs of lateral veins, often with a faint vein-like line at each side of the midrib. Inflorescence an axillary fascicle, 5–8-flowered. Flowers bisexual, regular, 5-merous, white; pedicel slender, 0.5–1 cm long; sepals fused at base, triangular, 1–2 mm × 1 mm; petals free, oblong, up to 5 mm long, shortly clawed at base and with nectar-producing appendage at base inside; stamens 10, fused at base, 3–5 mm long; ovary superior, obovoid, c. 1.5 mm long, 3-celled, styles 3, fused for more than half their length, stigmas head-shaped. Fruit an oblong to ovoid drupe c. 1 cm long, red when ripe, stone 3-celled but only 1-seeded. Seedling with epigeal germination; hypocotyl 3–3.5 cm long, epicotyl 6–7 mm long, glabrous; cotyledons leafy, narrowly oblong, c. 2 cm long; first leaves opposite.

Other botanical information

Erythroxylum comprises approximately 200 species and occurs throughout the tropics, most of them in South America. Erythroxylum coca Lam. is best known, as the source of coca leaves and cocaine. In tropical Africa about 10 species are found.

Erythroxylum fischeri

Erythroxylum fischeri Engl. is an evergreen, much-branched shrub or small to medium-sized tree up to 18 m tall, with straight bole up to 60 cm in diameter. It occurs in evergreen and riverine forests and thickets up to 1350 m altitude in DR Congo and from southern Sudan and western Ethiopia southward to Tanzania. Its hard and durable wood is used for poles in house building and for utensils such as spoons. It is suitable as garden ornamental or pot plant, and in Ethiopia the leaves are used as fodder for goats. The gum exudate is used as glue and in the preparation of medicines.

Anatomy

Wood-anatomical description (IAWA hardwood codes):

• Growth rings: 2: growth ring boundaries indistinct or absent.
• Vessels: 5: wood diffuse-porous; (10: vessels in radial multiples of 4 or more common); 13: simple perforation plates; 22: intervessel pits alternate; (23: shape of alternate pits polygonal); 25: intervessel pits small (4–7 μm); 30: vessel-ray pits with distinct borders; similar to intervessel pits in size and shape throughout the ray cell; 31: vessel-ray pits with much reduced borders to apparently simple: pits rounded or angular; 42: mean tangential diameter of vessel lumina 100–200 μm; 48: 20–40 vessels per square millimetre.
• Tracheids and fibres: 61: fibres with simple to minutely bordered pits; 66: non-septate fibres present; 69: fibres thin- to thick-walled.
• Axial parenchyma: (76: axial parenchyma diffuse); 78: axial parenchyma scanty paratracheal; 92: four (3–4) cells per parenchyma strand; 93: eight (5–8) cells per parenchyma strand.
• Rays: 97: ray width 1–3 cells; (106: body ray cells procumbent with one row of upright and/or square marginal cells); 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; 113: disjunctive ray parenchyma cell walls present; 115: 4–12 rays per mm.
• Mineral inclusions: 136: prismatic crystals present; 142: prismatic crystals in chambered axial parenchyma cells.

(E.A. Obeng, P.E. Gasson & E.A. Wheeler)

Growth and development

Erythroxylum mannii is considered to be a pioneer. In Guinea, Ghana and Gabon saplings have been recorded to be common in disturbed forest. Growth of young trees is fast; in Guinea they reached a height of about 12 m and a bole diameter of 11 cm 6 years after planting in the open and a height of about 7 m in the understorey of degraded forest. The mortality was low, less than 9% 6 years after planting. In Ghana young trees reportedly reached a height of 20 m and a bole diameter of 15 cm on logging roads of 4 years old. In natural forest in Côte d’Ivoire, the mean annual diameter growth was recorded as 3.5 mm over a period of 14 years, and in an arboretum in Cameroon it was 5 mm for trees of 50 years old, with some trees reaching 12 mm/year.

Erythroxylum mannii is often not truly deciduous; it produces new leaves well before all old ones are shed. In Sierra Leone it changes its leaves in September–November. Flowering occurs at the end of the dry season, in April–May, fruiting mainly in July–August. In Côte d’Ivoire fruits mature in June–July. They are eaten by birds, which disperse the seeds.

Ecology

Erythroxylum mannii occurs scattered or in small groups in evergreen forest and slightly more commonly in semi-deciduous forest.

Propagation and planting

Fruits are collected during the rainy season. In Guinea it has been proposed to clear the understorey under fruiting trees to facilitate fruit collection; the seedlings developing from germinating fruits can be transplanted to the nursery. There are about 25,000 fruit stones per kg. They start to germinate 2–4 weeks after sowing. The germination rate is usually low, 2–30%. In each pot 3–5 fruit stones are placed. Shading is not necessary during germination, but is recommended after germination and is progressively reduced 1.5 months before planting seedlings into the field. Seedlings can be planted out after 9 months, when they reached about 45 cm tall.

Management

In forest in eastern Sierra Leone average densities of 0.6 trees with a bole diameter of 20–40 cm have been recorded per ha, 0.2 trees with a bole diameter of 40–60 cm per ha, and 0.05 trees with a bole diameter of more than 60 cm per ha. In Cameroon average densities of up to 0.15 trees with a bole diameter of more than 60 cm have been recorded per ha, with a mean wood volume of up to 1 m³/ha.

In plantations in Guinea a first thinning has been done 4–7 years after planting at a spacing of 3 m × 3 m, depending on soil fertility. Erythroxylum mannii can be planted in agroforestry systems in association with banana.

Harvesting

The minimum bole diameter allowed for harvesting Erythroxylum mannii trees is 50 cm in Cameroon and 70 cm in the Central African Republic and Gabon.

Yield

Mature trees usually produce 4–7 m³ of bole wood.

Genetic resources

Erythroxylum mannii is widespread and although it usually occurs scattered in low densities, there are no indications that it is in danger of genetic erosion.

Prospects

The wood of Erythroxylum mannii is likely to remain important for local applications because of its good drying and processing properties. The amounts of timber available are nowhere sufficiently common to become an important commodity in the international market. However, as a reputedly fast-growing pioneer species, investigations into its prospects as a plantation timber tree are warranted.

Major references

• Badré, F., 1972. Erythroxylaceae. Flore du Cameroun. Volume 14. Muséum National d’Histoire Naturelle, Paris, France. pp. 51–56.

• 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.

• CTFT (Centre Technique Forestier Tropical), 1950. Landa. Fiches botaniques, forestières, industrielles et commerciales. Bois et Forêts des Tropiques 13: 43–46.

• 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.

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

• Normand, D., 1937. Le bois du Landa, Erythroxylum du Cameroun. Revue de Botanique Appliquée et d’Agriculture Tropicale 17(196): 883–889.

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

Other references

• Anonymous, 1960. Résultats des observations et des essais effectués au Centre Technique Forestier Tropical sur le landa (Erythroxylum mannii Oliv.). Information technique No 71, Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 5 pp.

• Aubréville, A., 1959. La flore forestière de la Côte d’Ivoire. Deuxième édition révisée. Tome premier. Publication No 15. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 369 pp.

• Badré, F., 1973. Erythroxylaceae. Flore du Gabon. Volume 21. Muséum National d’Histoire Naturelle, Paris, France. pp. 49–54.

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

• Chudnoff, M., 1980. Tropical timbers of the world. USDA Forest Service, Agricultural Handbook No 607, Washington D.C., United States. 826 pp.

• 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.

• Friis, I. & Vollesen, K., 1985. Additions to the Flora of Ethiopia. Willdenowia 14(2): 355–371.

• Friis, I. & Vollesen, K., 1998. Flora of the Sudan-Uganda border area east of the Nile. I. Catalogue of vascular plants, 1st part. Biologiske Skrifter No 51:1. The Royal Danish Academy of Sciences and Letters, Copenhagen, Denmark. 388 pp.

• Gilbert, G., 1958. Erythroxylaceae. In: Robyns, W., Staner, P., Demaret, F., Germain, R., Gilbert, G., Hauman, L., Homès, M., Jurion, F., Lebrun, J., Vanden Abeele, M. & Boutique, R. (Editors). Flore du Congo belge et du Ruanda-Urundi. Spermatophytes. Volume 7. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 54–57.

• Hubert, D., undated. Sylviculture des essences de forêts denses humides d’Afrique de l’Ouest. 187 pp.

• Isa Ipor, 1998. Erythroxylum P. Brown. In: Sosef, M.S.M., Hong, L.T. & Prawirohatmodjo, S. (Editors). Plant Resources of South-East Asia No 5(3). Timber trees: Lesser-known timbers. Backhuys Publishers, Leiden, Netherlands. pp. 223–224.

• Keay, R.W.J., 1958. Erythroxylaceae. In: Keay, R.W.J. (Editor). Flora of West Tropical Africa. Volume 1, part 2. 2nd Edition. Crown Agents for Oversea Governments and Administrations, London, United Kingdom. pp. 355–356.

• 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.

• Kerharo, J. & Bouquet, A., 1950. Plantes médicinales et toxiques de la Côte d’Ivoire - Haute-Volta. Vigot Frères, Paris, France. 291 pp.

• Lovett, J.C., Ruffo, C.K., Gereau, R.E. & Taplin, J.R.D., 2007. Field guide to the moist forest trees of Tanzania. [Internet] Centre for Ecology Law and Policy, Environment Department, University of York, York, United Kingdom. http://celp.org.uk/ projects/ tzforeco/. March 2012.

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

• Tailfer, Y., 1989. La forêt dense d’Afrique centrale. Identification pratique des principaux arbres. Tome 2. CTA, Wageningen, Pays-Bas. pp. 465–1271.

• Verdcourt, B., 1984. Erythroxylaceae. In: Polhill, R.M. (Editor). Flora of Tropical East Africa. A.A. Balkema, Rotterdam, Netherlands. 12 pp.

• Voorhoeve, A.G., 1965. Liberian high forest trees. A systematic botanical study of the 75 most important or frequent high forest trees, with reference to numerous related species. Pudoc, Wageningen, Netherlands. 416 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.

Sources of illustration

• Badré, F., 1972. Erythroxylaceae. Flore du Cameroun. Volume 14. Muséum National d’Histoire Naturelle, Paris, France. pp. 51–56.

• 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.

Author(s)

• L.P.A. Oyen, PROTA Network Office Europe, Wageningen University, P.O. Box 341, 6700 AH Wageningen, Netherlands

• D. Louppe, CIRAD, Département Environnements et Sociétés, Cirad es-dir, Campus international de Baillarguet, TA C 105 / D (Bât. C, Bur. 113), 34398 Montpellier Cédex 5, France

Correct citation of this article

Oyen, L.P.A. & Louppe, D., 2012. Erythroxylum mannii Oliv. [Internet] Record from PROTA4U. 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. <http://www.prota4u.org/search.asp>.

Accessed 1 April 2025.

• See the Prota4U database.