Timber and Related Products

Acajou
Wood type Hardwood
Environmental Not listed in CITES. Believed available from well-managed sources. Check certification status with suppliers.
Introduction The name African mahogany covers all species of Khaya, although their timbers vary somewhat in character, particularly in weight. The bulk of the timber shipped is produced by Khaya ivorensis and Khaya anthotheca, each with moderately lightweight, pale to medium-red wood, and it is timber of this type which is accepted commercially as African mahogany.
East African Khaya nyasica is generally similar.
A small proportion of Khaya grandifoliola is moderately light in weight but much of its timber and that of Khaya senegalensis is darker and appreciably heavier than that normally accepted as African mahogany. It has been suggested that such heavy wood should be marketed separately, and the name heavy African mahogany is recommended.
Distribution K. ivorensis occurs in the coastal rain forests of West Africa from the Ivory Coast to the Cameroons and Gabon, including those of Ghana and Nigeria.
K. anthotheca grows in West Africa in areas with lower rainfall than K. ivorensis requires, and is not found in the coastal belt; in East Africa it is confined mainly to Uganda and Tanzania.
K. grandifoliola grows at some distance from the West African coastal belt, in districts of relatively low rainfall.
K. nyasica occurs in East and Central Africa, particularly in Uganda and Tanzania.
K. senegalensis is found in the west from Senegal to Zaire and across the continent to Sudan and Uganda.
The Tree K. ivorensis grows to a height of 30m or more with a clear bole 12m to 25m in length above the buttresses, and with a diameter of 1.0m upwards to 2.0m or more. The habit of all Khaya species varies considerably with the growth conditions, but the banks of rivers and streams appear to suit the requirements of the species better than drier soils.
Thus K. anthotheca is usually not such a good shape as K. ivorensis, and K. grandifoliola is not so tall, and generally has a more crooked growth habit, though it usually attains a larger girth than other species.
K. senegalensis is a smaller tree and not so well shaped as the usual types of commercial mahogany. It grows mainly in the deciduous Savannah forests and generally reaches a height of 15m to 24m with a diameter of about 1.0m.
The Timber AFRICAN MAHOGANY
ie, K. ivoiensis, K. anthotheca and K. grandifoliola (in part).
The heartwood is distinctly pink when freshly sawn, but when seasoned varies in colour from light pinkish-brown to a deep reddish shade; the yellowish-brown sapwood is not always clearly demarcated. The heartwood of K. grandifoliola tends to be darker. The grain is usually interlocked and the texture is of a coarser nature than that of American mahogany. The quality varies with the locality of growth; some localities are said to produce coarse-textured logs with spongy hearts while others are noted for the fine texture and character of their timber. A common feature is the defect known as 'thunder shake' (cross fractures), which are particularly abundant in trees with a soft or 'punky' heart. K. nyasica from East Africa inclines to a reddish or golden-brown shade.
HEAVY MAHOGANY (dry-zone mahogany)
ie K. senegalensis and K. grandifoliola (in part).
The timber of both these species is appreciably denser, and typically darker than ordinary commercial African mahogany, K. senegalensis in particular being deep red-brown with a purple tinge. In respect of grain and texture, there is little difference from the characteristics of African mahogany, but K. grandifoliola is reputed to be of high quality.
Drying African mahogany dries fairly rapidly with generally little degrade. Care should he taken to prevent distortion and splitting, and this aspect is of greater importance when drying heavy mahogany.
Strength The strength of African mahogany compares favourably with that of American mahogany (Swietenia), but is more resistant to splitting. No data is available regarding strength of heavy mahogany although it can be assumed the heavier species are stronger than African mahogany.
Working Qualities Medium - Medium
Durability Moderately durable
Treatability Extremely difficult
Moisture
Movement
Small
Density
(mean, Kg/m³)
530 (Denisty can vary by 20% or more)
DensityText Denisty can vary by 20% or more
Texture Medium
Availability Regular
Price Low to medium
Use(s) Exterior joinery, Interior joinery, Furniture
Colour(s) Reddish brown