Afrormosia: African teak

Afrormosia, also known as African teak (as well as assembla, ayin, egba, kokrodua and assamela), is an African species that has been harvested during the last 50 years almost to extinction. The main supplies of this tree were in the Ivory Coast, Ghana, and Nigeria, with smaller supplies in Cameroon and the Democratic Republic of Congo.

The wood has traditionally been used for boat building, joinery, flooring, furniture and even decorative veneers. It’s considered an excellent teak substitute. In fact, because the wood resembles teak in appearance and has even more attractive strength and working properties (especially decay and insect resistance and very low movement with humidity changes), the tree has been heavily logged during the past 50 years.

Today, illegal logging and continued illegal exportation threaten this tree with extinction. A continued market demand for this wood today encourages these illegal activities and will eliminate this species from the African forests in the next decade. Some African foresters have established small plantations to attempt to preserve a limited genetically diverse stock of these trees, but often political strife and illegal activities doom even these well-meaning activities.

The tree itself may reach as high as 150 feet, with the first branch occurring 100 feet or higher off the ground. Diameters range from 3 to 5 feet. When sawn into lumber, there are a lot of clear, wide pieces. 
When all is considered, it’s the nearly perfect wood. 

Processing suggestions and characteristics
Density. The wood of afrormosia is similar in density to northern red oak, with a density of dry lumber just over 40 pounds per cubic foot. A board foot of kiln-dried lumber would weigh about 3-1/2 pounds.

Drying. Drying is slow, but without significant quality losses. Shrinkage in drying is only about 5 percent, which is quite low.

Gluing and machining. The wood glues with some difficulty, as with all dense woods. Surfaces must be very flat and true. Machining characteristics are very good. Occasional interlocked grain will cause machining problems if tools are not very sharp. There’s no silica in this wood, so dulling is not real rapid. 

Stability. This wood is fairly stable, but not quite as good as teak. It takes a 5 percent MC change for a 1 percent size change in the tangential direction (width of flatsawn lumber) and nearly 10 percent MC change for a 1 percent size change in the radial direction (width of quartersawn lumber).

Strength. Afrormosia has excellent strength and stiffness. The strength (MOR) of afrormosia is 18,400 psi. The bendability (MOE) is 1.94 million psi. The hardness is 1,560 pounds. 

Color and grain. The wood is a golden tan when first sawn, but the color rapidly darkens to a medium to dark brown upon exposure to air and light. The wood finishes well. Dark stains are likely if the wood is in contact with iron under damp conditions, similar to oak. Wood bleach or oxalic acid can remove this stain.


Have something to say? Share your thoughts with us in the comments below.

Profile picture for user genewengert
About the author
Gene Wengert

Gene Wengert, “The Wood Doctor” has been training people in efficient use of wood for 45 years. He is extension specialist emeritus at the University of Wisconsin-Madison.