Wood of the Month:
Afzelia Species Offer Exceptional Durability and Stability

By Jo-Ann Kaiser


FAMILY NAME
Afzelia bipindensis, Afzelia pachyloba, Afzelia africana and Afzelia quanzensis of the Family Leguminosae

COMMON NAMES
Afzelia, doussie, apa, aligna, lingue, papao, bolengu, mu mangala, chamfuta, chanfuta, mbemebakofi, mkora, mkola, mussacossa, beyo, meli, azza, bilinga, counterwood, mahogany-bean tree, pod-mahogany, Rhodesian mahogany and uvala.

HEIGHT/WEIGHT
Height ranges between 80 to 120 feet with diameters of three to five feet or more. Large irregular buttresses sometimes present. Weight ranges from 39 to 59 pounds per cubic foot with an average weight of 51 pounds per cubic foot. Basic specific gravity is 0.67.

PROPERTIES
Material seasons well but slowly. Experts recommend a kiln schedule of T6-D2 for 4/4 stock and T3-D1 for 8/4 stock. Movement in service is rated as small. Grain is straight to interlocked. Material can be difficult to work with hand or power tools, causing rapid dulling to cutting surfaces. Wood is difficult to stain, especially when material has yellow deposits. Experts recommend filling grain for best finish. Dust may be irritating. Can be difficult to glue. Extremely resistant to preservative treatments.

Afzelia is a fine wood on its own, but it is also one of those woods better known because of its similarity to other species. Afzelia offers durability and stability to a degree that invokes comparisons to teak. Its hardness is said to equal that of oak and in looks it resembles iroko.

Four species of Afzelia are commercially important: Afzelia africana, Afzelia bipindensis, Afzelia pachyloba and Afzelia quanzensis. The trees grow in West, Central and East Africa. Afzelia species thrive in varied conditions, from dense evergreen forests to savanna and coastal forests.

Durability a Key
The commercial species of afzelia share key traits. The wood is exceptionally stable and durable. Albert Constantine Jr., in the book, Know Your Woods, says afzelia has been used as a teak substitute because of its exceptional stability. "During World War II, afzelia was accepted as a substitute for teak in the United Kingdom for use in shipbuilding and for switchboards, laboratory benches, etc."

Uses for afzelia include interior and exterior joinery, heavy construction, doors, windows, staircases, flooring, ship's rails, countertops, garden furniture, residential and contract furniture. The wood resists acid and is used for laboratory equipment, chemical containers, and vats. The sapwood is susceptible to powder post beetle infestation, but the heartwood is considered extremely durable and stable, with natural termite and teredo (shipworm) resistance. This natural resistance makes it a popular choice for heavy construction uses.

Afzelia species are sometimes sliced for decorative veneer. Jim Dumas of Certainly Wood in East Aurora, NY, has received a few calls for the veneer and has supplied it, but it is far from one of his big sellers. "We sold 20,000 square board feet of afzelia veneer to a client who used it for residential doors among other things," said Dumas.

Quality Flooring Source
Afzelia is used to make beautiful plank and parquet flooring. Wood from the tree darkens considerably after it is cut and varies widely in color from a golden-brown to a reddish brown. Interesting hardwood flooring looks can be achieved by teaming various colors together.

Afzelia species go by a long list of names. In the United States, the most common commercial names are afzelia and doussie. In Nigeria, it might be called lingue while in the Ivory Coast it goes by papao. In Zaire the wood is known as bolengu but in Gabon it is called mu mangala and chamfuta in Mozambique. The tree is sometimes called counterwood, probably because that's one of its common uses.

Chemical Staining
In the book World Woods In Color, author William A. Lincoln mentions the working properties of the wood. "It is difficult to stain, but when the grain is filled, it polishes (finishes) very well." He adds that afzelia is "Liable to chemical staining due to yellow dyestuff (afzelin) in the pores, which may discolor textiles." Under moist conditions, afzelin can also stain paper and other cellulosic materials.

The texture of the wood is moderate to coarse with a grain that ranges from straight to interlocked. Sawing and machining can be difficult because the material has a rapid dulling effect to cutting edges. This high resistance to cutting can be mitigated by reducing the cutting angle, say experts.

                                                                                                                                                                                           

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