Celtis spp.

African Celtis

Family: Ulmaceae

Other Common Names: Esa (Ghana), Ba (Ivory Coast), Akasinsa (Uganda), Ita, Ohia (Nigeria), Mrinde, Mrunde (Tanzania).

Distribution: Trees are found in western, central, and parts of eastern Africa; locally frequent in the drier high forests.

The Tree: Up to 130 ft in height with a clear straight bole to 80 ft; trunk diameters to 3 ft over short to long buttresses.

The Wood:

General Characteristics: Heartwood and sapwood not clearly demarcated, whitish or light yellow, becoming grayish white on exposure often with dark irregular markings. Texture rather fine to coarse; grain straight to irregular, wavy, or interlocked; lustrous; has an apple-like scent in C. africana.

Weight: Basic specific gravity (ovendry weight/green volume) variable with species 0.52 to 0.65; air-dry density 40 to 50 pcf.

Mechanical Properties: (First and third sets of data based on the 2-cm standard; second set on the 2-in. standard.)

Moisture content Bending strength Modulus of elasticity Maximum crushing strength

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

Green (40) 13,050 1,850 6,500

12% 20,900 2,300 10,550

12%(5) 14,700 1,620 NA

12%(44) 11,500 1,700 6,150

Janka side hardness 1,390 lb for green material and 1,670 lb for dry.

Drying and Shrinkage: Dries fairly rapidly with little degrade, some end-checking and warp may occur. Kiln schedule T10-D45 is suggested for 4/4 stock and T8-D3S for 8/4 Shrinkage green to ovendry: radial 5.6%; tangential 10.4%; volumetric 15.4%. Movement in service is rated as medium.

Working Properties: Generally reported easy to work in machining operations but rather difficult with hand tools; tearing of interlocked grain in planing, poor surfaces in shaping; nails and glues easily; moderate steam-bending qualities.

Durability: Highly susceptible to attack by decay and staining fungi as well as insect damage, including powder-post beetle attack.

Preservation: Heartwood rated as moderately resistant to preservative treatment, sapwood is permeable.

Uses: Flooring, tool handles, plywood, general construction, decorative veneer.

Additional Reading: (3), (5), (9), (40), (44)