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| Commercial timbers |
Nomenclature etc. FABACEAE-FABOIDEAE. Trade and local names: nson-so (GA), awong (CM), n'toko, n'gondou (CG), dikela, kiboto, mboto, monkonge, mundambi, bokonge, tshikalakala (CD). Not protected under CITES regulations.
Tree. Geographic distribution: tropical Africa.
General. Growth ring boundaries distinct. Demarcated by fine and occasionally discontinuous marginal parenchyma bands. Heartwood basically brown to black; with streaks. Sapwood colour distinct from heartwood colour. Odour indistinct or absent. Density 0.75–0.8 g/cm³. Colour striping not due to coloured deposits but periodical structural changes (from light coloured parenchyma to dark fibers.
Vessels. Wood diffuse porous. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 155–265–320 µm. Average number of vessels/mm² 1–3. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 6–8 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Other deposits present (dark brown).
Tracheids and fibres. Fibres very thick-walled. Average fibre length 1540–1760–2060 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma banded. Bands marginal (or seemingly marginal) or not marginal (or seemingly marginal). Axial parenchyma bands much wider than rays. Bands fine or coarse. Widest parenchyma bands often completely include vessels. Axial parenchyma paratracheal. Paratracheal axial parenchyma aliform to confluent. Aliform parenchyma of the lozenge type. Axial parenchyma fusiform and as strands. Average number of cells per strand: 2–4.
Rays. Rays 6–8 per tangential mm, multiseriate, 2–4 cells wide. Height of large rays up to 500 µm. 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, fibres storied. Number of ray tiers per axial millimetre 4–5.
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, or red, or yellow. Ethanol extract fluorescent (yellowish green in variable intensity). Colour of ethanol extract colourless to brown, or red. Froth test positive. Splinter burns to partial ash. Ash white to grey.
Illustrations. • Macroscopic images. transverse (ca. 10x). tangential (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’.
