Commercial Timbers


H. G. Richter and M. J. Dallwitz

Millettia laurentii De Wild. (Wengé)

Nomenclature etc. FABACEAE-FABOIDEAE. Trade and local names: wengé (DE, BE, FR, GB, NL, CD), 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. 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 short (2–3 vessels) radial rows. Two distinct vessel diameter classes absent. 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, vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Tyloses in vessels absent. Other deposits in heartwood vessels present (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. Axial parenchyma bands marginal (or seemingly marginal). Widest parenchyma bands often completely include vessels. Axial parenchyma paratracheal. Paratracheal axial parenchyma vasicentric to confluent. Axial parenchyma fusiform and as strands. Average number of cells per axial parenchyma strand 2–4.

Rays. Rays 6–8 per tangential mm, multiseriate (also if only few), 2–4 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, fibres storied.

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; basically yellow or shade of yellow. Heartwood extractives not leachable by water. Ethanol extract fluorescent (yellowish green in variable intensity). Colour of ethanol extract colourless to brown or shade of brown, or red or shade of red. Froth test positive.

Illustrations. • Macro images. Millettia laurentii. Transverse. Tangential. • Transverse section. Millettia laurentii. • Tangential section. Millettia laurentii. • Radial section. Millettia laurentii.

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: 25th June 2009.’.