BOTANICAL NAME: Aucoumea klaineana of the family Burseraceae
COMMON NAMES: bengouma, cape lomez mahogany, combogala, gaboon, gaboon mahogany, gaboon wood, koumi, m'goumi, mofoumou, mofoumou., moukoumi, n'goumi, n'koum, n'koumi, n'koumi (gabon), n'kumi, ojoume, okoum, okoume, okoumé angouma, ongoumi, uume, zouga
The most widely used alternate common name in the USA is okoume
COLOR:The heartwood is salmon pink to light pinkish brown, or reddish brown. Exposure to light is reported to bring a gradual change to the color, which eventually attains an appearance similar to the mahoganies. The sapwood is white or pale gray, and not clearly demarcated from the heartwood.
GRAIN / TEXTURE / FILLER / FINISH / LUSTER: Grain is usually straight but sometimes interlocked and wavy, producing an attractive striping on quarter-sawn surfaces and sometimes a nice mottle surface. The texture is medium to fine and uniform. General finishing qualities are rated as good. It polishes well to a lustrous surface and takes stains well, varnishes moderately well. Machined surfaces are sometimes a little woolly but can be worked to a good finish.
PROPERTIES / WORKABILITY: It is a very soft, weak wood, with medium to low ratings in all strength and crushing properties but despite this, it can be tough on cutting edges due to a high silica content. Reports on ease of sawing range from moderate to difficult. Glues, screws, and nails well without need for pre-drilling, sands easily, easy to carve, turns well (but can fuzz up). Works fairly easily with both hand and machine tools, but worked surfaces tend to be woolly. A reduced cutting angle of 20 degrees is recommended in planing to prevent tearing. Bores easily, mortises and moulds well.
Veneers easily and is often rotary cut for laminated work, and figured wood is sliced into highly decorative veneers for paneling and the manufacture of cabinets.
Natural growth defects: cross-shakes or thunder shakes are reported to be rather common, and large Gaboon logs sometimes have a brashy core.
DURABILITY: Gaboon is reported to have very little natural resistance to decay, and the heartwood is susceptible to attack by marine borers. Logs are susceptible to forest longhorn beetle attack, and the sapwood is readily attacked by powder-post beetles. The Heartwood is resistant to preservative treatments, sapwood is less resistant.
STABILITY: movement in service is generally reported as moderate, but my own experience is that it is small
BENDING: steam bending rating is poor
ODOR / TASTE: no distinct odor or taste
SOURCES: Equatorial Africa including Congo, Equatorial Guinea, Gabon, Rio Muni, Zaire
USES: boat building (general), boxes and crates, building construction, building materials, cabinetmaking, canoes, carvings, cigar boxes, construction, cooperages, corestock, decorative plywood, decorative veneer, figured veneer, fine furniture, flooring, furniture, furniture components, inside joinery, interior construction, interior trim, joinery, light construction, luxury items, millwork, moldings, moulding, musical instruments, paneling, particleboard, plywood, pulp/paper products, surface veneer in panelling and furniture, tool handles, turnery, vats, vehicle parts, veneer
Okoume is widely use in marine plywood because although it is not a particularly strong wood, it is very light and thus has a decent strength to weight ratio while having the light weight that is important in shipbuilding. When using okoume marine plywood, it is essential that all edges be epoxied (or protected in a similar way) otherwise it can rot.
TREE: Tall and large, with a normal height of 100 to 130 feet, sometimes up to 200 feet, and a trunk diameter of 3 to 8 feet. It usually produces a slightly curved but cylindrical bole that is clear of branches to 70 feet and above.
WEIGHT: reported as 15 to 30 lbs per cubic foot, which is QUITE a range, especially given that there is only one reported species
DRYING: The wood dries rapidly and well, with little degrade or defect. Shrinkage is reported to be medium. Slight checking and distortion may occur during drying.
AVAILABILITY: The timber is plentiful within its growth range, but supplies, especially in the lumber form, are very limited on the U.S. Market. Some reports say that the veneer form is plentiful in the USA.
COST: Inexpensive, except highly figured types which, when available, are priced in the expensive range
TOXICITY: some adverse effects on skin