USDA Forest Service
Forest Products Laboratory
One Gifford Pinchot Drive
Madison, WI 53705-2398
(608) 231-9200

 

Wood Technical Fact Sheet

 

 Mitragyna ciliata

Abura

Family: Rubiaceae

Other Common Names: M'Boy (Sierra Leone, Liberia), Bahia (Ivory Coast), Baya, Subah (Ghana), Elolom (Cameroon), Elelom (Gabon), Vuku, M'Voukou (Zaire), Nzingu (Zambia, Uganda).

Distribution: Mainly West Africa from Sierra Leone to the Congo region and Angola, gregarious in freshwater swamps.

The Tree:

Reaches a height of over 100 ft; boles straight and clear to 60 ft; usually free from buttresses; trunk diameter 3 to 5 ft.

The Wood:

General Characteristics: Heartwood uniform light yellowish- or pinkish brown; sapwood wide, not usually differentiated. Texture fine and even; grain moderately straight to interlocked or spiral; luster low; sometimes with gum veins that appear as dark streaks; freshly cut timber has an unpleasant odor. Silica up to 0.24% is reported.

Weight: Basic specific gravity (ovendry weight/green volume) 0.45; air-dry density 34 pcf.

Mechanical Properties: (2-cm standard)

Moisture content Bending strength Modulus of elasticity Maximum crushing strength

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

Green (9) 7,900 1,180 3,960

12% 12,100 1,350 6,740

12% (47) 10,300 1,020 5,600

Janka side hardness 700 lb for green material and 780 lb for dry. Amsler toughness 116 in.-lb at 12% moisture content (2-cm specimen).

Drying and Shrinkage: Dries rapidly with little or no degrade. Kiln schedule T13-C4S is suggested for 4/4 stock and T11-D3S for 8/4. Shrinkage green to ovendry: radial 4.1%; tangential 9.0%; volumetric 12.0%. Movement in service is rated as small.

Working Properties: Works well with both hand and machine tools and takes a good finish if cutters are kept sharp; blunting is slight to severe because of silica; easy to glue; veneers easily.

Durability: Heartwood is not durable nor resistant to termites; sapwood liable to powder-post beetle attack. Good acid resistance.

Preservation: Heartwood moderately resistant to preservative treatments; sapwood is permeable.

Uses: A general-purpose timber, furniture components, joinery, domestic flooring, plywood, carving.

Additional Reading: (3), (9), (34), (47)