USDA Forest Service
Forest Products Laboratory
One Gifford Pinchot Drive
Madison, WI 53705-2398
Wood Technical Fact Sheet
Other Common Names: Sapo, Bondu (Liberia), Ekop Zing (Cameroon).
Distribution: West Africa in evergreen rain forests.
The Tree: May reach a height of 180 ft, bole clear to 80 ft, straight and cylindrical; trunk diameter usually about 2 to 3 ft but may reach 4 to 5 ft, swollen at the base.
General Characteristics: Heartwood light brown to brown, sometimes with a greenish tint on the sapwood boundary; sapwood about 2 in. wide, reddish white to a light brown, clearly differentiated. Texture coarse; grain straight to interlocked; without characteristic odor.
Weight: Basic specific gravity (ovendry weight/green volume) about 0.53; air-dry density 41 pcf.
Mechanical Properties: (2-cm standard)
Moisture content Bending strength Modulus of elasticity Maximum crushing strength
(%) (Psi) (1,000 psi) (Psi)
12% (46) 13,400 1,250 7,600
12% (37) 14,700 1,690 7,450
Amsler toughness 315 in.-lb at 12% moisture content (2-cm specimen).
Drying and Shrinkage: Must be seasoned with care as there is a marked tendency to end-split and check on drying. A mild kiln schedule is reported to give good results. Shrinkage green to ovendry: radial 3.8%; tangential 9.0%; volumetric 12.8%.
Working Properties: Works fairly well with hand and machine tools, planes to a good finish but there is some tearing of interlocked grain, glues well, peels and slices well into veneers.
Durability: Heartwood is moderately durable but liable to termite attack.
Preservation: Heartwood resistant to impregnation; sapwood permeable.
Uses: Core stock for plywood and blockboard, decorative veneers, particleboard, furniture components, joinery.
Additional Reading: (3), (37), (46)