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| Commercial timbers |
Nomenclature etc. FABACEAE-FABOIDEAE. Syn.: Afrormosia elata. Trade and local names: afromosia (DE, GB, NG); krokodua (BE, GH); assamela (CI, FR); obang (CM); bohala, wahala (CF). Listed in CITES Annex II.
Tree. Geographic distribution: tropical Africa (West and Central Africa).
General. Heartwood basically brown to yellow, yellow to green, brown to green; mostly without streaks (rarely with subtle striping). Sapwood colour distinct from heartwood colour. Density 0.6–0.65–0.7 g/cm³. Ribbon figure caused by periodic changes in vessel frequency and/or interlocked grain; growth increments macroscopically visible.
Vessels. Wood diffuse porous. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 80–110–150 µm. Average number of vessels/mm² 9–16–23. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 6–7 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Other deposits present, rarely with light coloured "chalky" deposits.
Tracheids and fibres. Fibres of medium wall thickness to very thick-walled. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma occasionally banded or not banded. Bands not marginal (or seemingly marginal). Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric, or aliform and confluent, or unilateral. Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 2–4.
Rays. Rays 7–12 per tangential mm, multiseriate, 1–3 cells wide. Rays composed of a single cell type (homocellular); homocellular ray cells procumbent.
Storied structures. Storied structure present, all rays storied, axial parenchyma storied, vessel elements storied. Number of ray tiers per axial millimetre 2–3.
Secretory structures. Intercellular canals absent.
Mineral inclusions. Crystals present, prismatic, located in axial parenchyma cells. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Silica not observed.
Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; colour of water extract colourless to brown. Heartwood extractives leachable when in contact with water (brownish). Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown, or yellow. Splinter burns to partial ash. Ash white to grey, or yellow-brown.
Illustrations. • Macroscopic images. transverse (ca. 10x). radial (natural size). • Transverse section. • Tangential section. • Radial section.
The interactive key allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting specified attributes, summaries of attributes within groups of taxa, and geographical distribution.
Cite this publication as: ‘Richter, H.G., and Dallwitz, M.J. 2000 onwards. Commercial timbers: descriptions, illustrations, identification, and information retrieval. In English, French, German, Portuguese, and Spanish. Version: 9th April 2019. delta-intkey.com’.
