Petersianthus macrocarpus (P. Beauv.) Liben

Combretodendron macrocarpum (Palisot de Beauvois) Keay

(Syn. C. africanum Welwitsch ex Bentham)

Standard trade name: Essia

Local name: Esia (Ghana)

A tree up to 150 ft high, usually 3 ft in diameter with a 12 ft girth around the buttressing. The tree displays a well-developed crown and a straight bole with buttresses. The leaves are 6 × 3 inches, obovate, and glabrous, with shallowly serrate margins. The white flowers are abundant in short, axillary racemes.

GENERAL DESCRIPTION.—The reddish brown heartwood is clearly delineated from the pale white sapwood, which is 3 in or more thick. Essia has a powerful, unpleasant odor when freshly felled. It is hard and heavy, weighing about 44–50 lb/ft3 seasoned and about 611 lb/ft3 green. The grain is interlocked and the texture medium.

SEASONING.—Dries slowly and very prone to check and split.

DURABILITY.—Moderately resistant. Damage by ambrosia beetles is sometimes present. The sapwood is permeable but the heartwood is extremely resistant to preservative treatment.

WORKING QUALITIES.—The timber is hard to work with hand and machine tools, but logs are sawed with little difficulty. The wood planes to a smooth finish using a 20° cutting angle. It does not take nails easily and requires prebored holes. It glues satisfactorily and takes stains effectively. It polishes to a satisfactory finish when a filler is used.

USES.—Used locally for heavy and general construction work by the mining companies. It is not suitable for peeling.

XYLEM ANATOMY.—Growth rings absent. Wood is diffuse-porous, as in many tropical woods. Vessels: solitary and multiples of two to eight, minute pores which are circular to ovate in shape with a few irregularly angular. Average pore diameter 68μm, range 18μm–89μm; average vessel element length 435μm, range 340μm–600μm; vessel wall thickness 3μm–4μm; perforation plates exclusively simple; vessel element end wall inclination is oblique to transverse with intervascular pitting alternate and small.