USDA Forest Service
Forest Products Laboratory
One Gifford Pinchot Drive
Madison, WI 53705-2398
(608) 231-9200

Wood Technical Fact Sheet

 Distemonanthus benthamianus

Ayan

Family: Leguminosae

Other Common Names: Movingui (Gabon), Barre (Ivory Coast), Bonsamdua (Ghana), Eyen (Cameroon), Ayanran (Nigeria).

Distribution: Widely but sparsely distributed throughout the high forests of West Africa, mainly in Cameroon, Ghana, and Nigeria.

The Tree: Reaches a height of 90 to 125 ft; bole reasonably straight, clear, and cylindrical; trunk diameters 2.5 to 4.5 ft over rather thin, weakly developed buttresses.

The Wood:

General Characteristics: Heartwood yellowish to yellow brown, sometimes with dark streaking; sapwood narrow, whitish or straw colored, fairly distinct. Texture fine grain often interlocked, sometimes wavy; lustrous; some logs produce a decorative figure; may contain up to 1.3% silica; contains a yellow extractive that may stain fabrics if moistened.

Weight: Basic specific gravity (ovendry weight/green volume) about 0.58; air-dry density 45 pcf.

Mechanical Properties: (2-cm standard)

Moisture content Bending strength Modulus of elasticity Maximum crushing strength

(%) (Psi) (1,000 psi) (Psi)

12% (9) 15,700 1,650 8,310

12% (44) 19,000 NA 9,800

Janka side hardness for dry material 1,230 lb. Amsler toughness 250 in.-lb for dry material (2-cm specimen).

Drying and Shrinkage: Air-dries well, though slowly, with little degrade. Kiln schedule T6-D4 is suggested for 4/4 stock and T3-D3 for 8/4. Shrinkage green to ovendry: radial 3.1%; tangential 5.2%; volumetric 10.7%. Movement in service is rated as small.

Working Properties: Works fairly readily with machine and hand tools. Blunting effect on cutters varies depending on silica content. Gum buildup on saws causes overheating. Takes a good finish, good gluing properties, easy to peel into veneer moderately good steam-bending properties.

Durability: Heartwood is rated as moderately durable and moderately resistant to termite attack.

Preservation: Heartwood resistant to impregnation.

Uses: Cabinetwork, joinery, flooring, decorative veneers. Suggested as an oak alternative.

Additional Reading: (3), (9), (32), (44)