Albizia spp.

Albizzia

Family: Leguminosae

Other Common Names: Okuro (Ghana), Ayinre, Uwowe (Nigeria), Mugavu, Nongo (Uganda), Mtanga, Mduruasi (Tanzania).

Distribution: Widely distributed throughout tropical Africa; mostly trees of the high forest are exploited, but also common in secondary forests.

The Tree: May reach heights of 120 to 150 ft with trunk diameters of 3 ft; some species with a total height of 60 ft and a diameter of 1.5 to 2.0 ft; sometimes buttressed; boles tend to be irregular in dry areas.

The Wood:

General Characteristics: Heartwood golden yellow, light brown, red brown, or dark brown, sometimes with a greenish, purple, or red tinge, sometimes with dark streaks sapwood whitish, yellowish, or pinkish brown, well demarcated. Texture variable from fine to coarse; grain straight to interlocked or irregular and wavy; may have a silky sheen; without characteristic odor or taste. Dust may irritate mucous membranes.

Weight: Basic specific gravity (ovendry weight/green volume) 0.45 to 0.59; air- dry density 35 to 45 pcf.

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

Moisture content Bending strength Modulus of elasticity Maximum crushing strength

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

Green (57) 7,235 850 4,300

12% 8,855 1,060 6,420

15% (66) 12,000 1,480 6,000

12% (4) 12,310 1,640 6,140

Janka side hardness 750 to 1,160 lb for dry material.

Drying and Shrinkage: Seasons slowly and with little or no degrade. Kiln schedule T6-D4 is suggested for 4/4 stock and T3-D3 for 8/4 (West African species). Shrinkage green to ovendry: radial 2.4%; tangential 3.8%. Movement in service is rated as small.

Working Properties: Saws and machines well and works easily with hand tools and dresses smoothly but with some tearing of interlocked grain; glues well. Intense irritation may be caused by the sawdust.

Durability: Heartwood moderately durable but generally vulnerable to termite attack.

Preservation: Heartwood impermeable to preservatives; sapwood is treatable.

Uses: Furniture, joinery, flooring.

Additional Reading: (3), (4), (57), (66)