Guibourtia arnoldiana (PROTA)

The wood is particularly suitable for indoor uses such as flooring, carpentry, furniture, panelling and stairs, but also for turning, carving and sliced veneer. It is used for vehicle bodies, boat building, small decorations, chess boards, sporting goods, toys, household implements, pool tables, pool cues, brushes, knives and flutes.

The exudate from the bole mixed with palm oil is used as an ointment to cure scabies, and as illuminant.

Production and international trade

The timber is mainly traded from Gabon under the trade name ‘mutenye’. The production is limited and quantities traded are actually small. In the 1960s, 2000–6000 m³ of logs were exported from Congo per year. In 1983 Gabon exported a maximum of 10,000 m³.

Properties

The heartwood is yellowish brown to pale olive brown or brown, often with greyish streaks, darkening on exposure. It is distinctly demarcated from the up to 8 cm wide, dull grey sapwood with a yellowish tinge when freshly cut. The grain is straight or slightly interlocked, texture moderately fine and fairly even. The wood surface is lustrous. A stripe figure is present on radial surfaces, and a flame pattern on tangential surfaces.

The wood is medium-weight to fairly heavy, with a density of 740–860 kg/m³ at 12% moisture content. Usually it air dries well but slowly; some care is needed because warping and checking may occur. The shrinkage rates are moderately high, from green to oven dry 4.6–6.0% radial and 8.7–10.3% tangential. Once dry, the wood is moderately stable in service. At 12% moisture content, the modulus of rupture is 138–202 N/mm², modulus of elasticity 14,000–21,400 N/mm², compression parallel to grain 72–84 N/mm², shear 8–13 N/mm², cleavage 25–35 N/mm and Chalais-Meudon side hardness 4.5–8.3.

The wood works satisfactorily with hand and machine tools, but the presence of silica may cause dulling of saw teeth and cutting edges. Stellite-tipped saw teeth and tungsten carbide cutting tools are advisable. The wood takes a good finish. The nailing and screwing properties are good, but pre-boring is needed. The wood glues satisfactorily, but the presence of gum may cause some difficulties. The bending properties are moderate. The wood is easy to peel and slice after steaming of the logs. It is moderately durable. It is fairly resistant to fungal attack and wood-boring insects, and moderately resistant to termites, but the sapwood is liable to Lyctus attack. The wood is quite resistant to marine borers. The heartwood is resistant to treatment with preservatives, the sapwood moderately resistant. When the wood is used as firewood, the smoke can provoke itching of the skin.

Adulterations and substitutes

The wood properties of Guibourtia arnoldiana are close to those of iroko (Milicia spp.) and teak (Tectona grandis L.f) and the wood can be used for similar purposes. In Europe sliced veneer is sometimes used as a substitute of walnut (Juglans regia L.). In DR Congo the trade name ‘mutenye’ is often used for Copaifera religiosa J.Léonard.

Description

Medium-sized tree up to 30 m tall; bole branchless for up to 20 m, straight and cylindrical or irregular, up to 100 cm in diameter, with buttresses up to 1 m high; bark surface orange-red, irregularly flaking leaving paler patches; crown with spreading branches.
Leaves arranged spirally, paripinnately compound with 1 pair of leaflets; stipules small and early caducous; petiole 4–8 mm long; leaflets sessile, obliquely ovate, 4–8 cm × 1–4 cm, slightly acuminate at apex, glabrous, with numerous translucent dots, pinnately veined with 7–9 pairs of lateral veins, 2–3 of which from base of leaflet.
Inflorescence a terminal or axillary panicle up to 10 cm long, brown short-hairy; bracts c. 1 mm long, early caducous.
Flowers bisexual, regular, whitish, nearly sessile; sepals 4, ovate-elliptical, 3–3.5 mm × 1.5–2.5 mm, short-hairy inside; petals absent; stamens 10, free, 6–10 mm long; disk cup-shaped, hairy; ovary superior, rounded, c. 2 mm in diameter, hairy, 1-celled, style 3–6 mm long.
Fruit an obliquely elliptical to obovate, flat pod 4–5 cm × 2.5–3 cm, with 2–6 mm long stipe, rounded at apex, with a c. 5 mm wide wing at one side, smooth, brown, reticulately veined, with papery walls, indehiscent, 1(–2)-seeded.
Seed rounded to ovoid, flattened, c. 2 cm long, brownish, without aril.

Other botanical information

Guibourtia comprises about 14 species, all African, but a single species occurs in tropical America. The genus is related to Hymenaea and Peltogyne.

Anatomy

Wood-anatomical description (IAWA hardwood codes):

Growth rings: 2: growth ring boundaries indistinct or absent.
Vessels: 5: wood diffuse-porous; 13: simple perforation plates; 22: intervessel pits alternate; 23: shape of alternate pits polygonal; 25: intervessel pits small (4–7 μm); 26: intervessel pits medium (7–10 μm); 29: vestured pits; 30: vessel-ray pits with distinct borders; similar to intervessel pits in size and shape throughout the ray cell; 42: mean tangential diameter of vessel lumina 100–200 μm; 47: 5–20 vessels per square millimetre; 58: gums and other deposits in heartwood vessels.
Tracheids and fibres: 61: fibres with simple to minutely bordered pits; 66: non-septate fibres present; 69: fibres thin- to thick-walled.
Axial parenchyma: 79: axial parenchyma vasicentric; 80: axial parenchyma aliform; 81: axial parenchyma lozenge-aliform; 83: axial parenchyma confluent; 89: axial parenchyma in marginal or in seemingly marginal bands; 91: two cells per parenchyma strand; 92: four (3–4) cells per parenchyma strand; (93: eight (5–8) cells per parenchyma strand).
Rays: 98: larger rays commonly 4- to 10-seriate; 104: all ray cells procumbent; 115: 4–12 rays per mm.
Mineral inclusions: 136: prismatic crystals present; 142: prismatic crystals in chambered axial parenchyma cells.

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

Ecology

Guibourtia arnoldiana is found in rainforest on well-drained localities up to 200 m altitude.

Handling after harvest

Freshly harvested logs should not be left too long in the forest to prevent fungal and insect attacks, or they should be treated with preservatives.

Genetic resources

Guibourtia arnoldiana is fairly widespread and not heavily exploited. Harvesting of straight boles and leaving irregular ones may result in a negative selection pressure.

Prospects

Although Guibourtia arnoldiana produces good-quality timber, other species seem to qualify better for promotion for research on domestication and plantation management. There is no information on growth rates and proper management methods of Guibourtia arnoldiana.

Major references

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

Aubréville, A., 1968. Légumineuses - Caesalpinioidées (Leguminosae - Caesalpinioideae). Flore du Gabon. Volume 15. Muséum National d’Histoire Naturelle, Paris, France. 362 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.

CIRAD Forestry Department, 2009. Mutenye. [Internet] Tropix 6.0. http://tropix.cirad.fr/africa/mutenye.pdf. December 2010.

Fouarge, J., Quoilin, J. & Roosen, P., 1970. Essais physiques, mécaniques et de durabilité de bois de la République Democratique du Congo. Série technique No 76. Institut National pour l’Etude Agronomique du Congo (INEAC), Brussels, Belgium. 40 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.

Sallenave, P., 1971. Propriétés physiques et mecaniques des bois tropicaux. Deuxième supplément. Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 128 pp.

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

Wilczek, R., Léonard, J., Hauman, L., Hoyle, A.C., Steyaert, R., Gilbert, G. & Boutique, R., 1952. Caesalpiniaceae. 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 3. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 234–554.

Other references

Anonymous, 1963. Mutenye. Informations techniques no 183, Centre Technique Forestier Tropical, Nogent-sur-Marne, France. 1 pp.

Fougère-Danezan, M., Herendeen, S., Maumont, S. & Bruneau, A., 2010. Morphological evolution in the variable resin-producing Detarieae (Fabaceae): do morphological characters retain a phylogenetic signal? Annals of Botany 105(2): 311–325.

Fougère-Danezan, M., Maumont, S. & Bruneau, A., 2007. Relationships among resin-producing Detarieae s.l. (Leguminosae) as inferred by molecular data. Systematic Botany 32(4): 748–761.

Fuhr, M., Delègue, M.-A., Nasi, R. & Minkoué, J.-M., 1998. Dynamique et croissance de l’Okoumé en zone côtière du Gabon. Document Forafri 16. Cirad-Forêt, Montpellier, France. 60 pp.

Léonard, J., 1949. Notulae Systematicae IV (Caesalpiniaceae-Amherstieae africanae americanaeque). Bulletin du Jardin botanique de l'Etat (Bruxelles) 19(4): 383–408.

Léonard, J., 1950. Etude botanique des copaliers du Congo belge. INEAC, série scientifique no 45. Bruxelles, Belgium. 158 pp.

Normand, D., 1950. Note sur les bois de Guibourtia arnoldiana et de Copaifera religiosa du Mayumbe. Bulletin du Jardin botanique de l'Etat a Bruxelles 20(1): 19-30.

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.

Sources of illustration

Wilczek, R., Léonard, J., Hauman, L., Hoyle, A.C., Steyaert, R., Gilbert, G. & Boutique, R., 1952. Caesalpiniaceae. 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 3. Institut National pour l’Étude Agronomique du Congo belge, Brussels, Belgium. pp. 234–554.

Author(s)

N. Nyunaï, Institut de Recherches Médicales et d’Etudes des Plantes Médicinales, B.P. 3805, Yaoundé, Cameroon

Correct citation of this article

Nyunaï, N., 2011. Guibourtia arnoldiana (De Wild. & T.Durand) J.Léonard. 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.