Celtis spp.
Family: Ulmaceae
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African Celtis

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-in. standard; second 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% (24)                     14,700                         1,620                             _

 

12% (20)                     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-checkin and warp may occur. Kiln schedule T10-D4S 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 planning, 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 permaeable.

 

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

 

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

3.  Bolza, E., and W.G. Keating. 1972. African timbers-the properties, uses, and characteristics of 700 species. CSIRO. Div. Of Build. Res., Melbourne, Australia.

5.  Bryce, J.M. 1967. The commercial timbers of Tanzania. Tanzanian For. Div. Util. Sec. Moshi.

9.  Farmer, R.H. 1972. Handbook of hardwoods. H.M. Stationery Office. London.

40.  Lavers, G.M. 1967. The strength properties of timbers. For. Prod. Res. Bull. No. 50. H.M. Stationery Office. London.

41.  Nigeria: Dep. For. Res. 1966. Brachystegia kennedyi (Okwen). For. Prod. Res. Rep. Dep. For. Res. Nigeria No. FPRL/7

 

From: Chudnoff, Martin. 1984. Tropical Timbers of the World. USDA Forest Service. Ag. Handbook No. 607.