Commercial Timbers


H. G. Richter and M. J. Dallwitz

Acacia mangium Willd. (Akasia, mangium)

Nomenclature etc. FABACEAE-MIMOSOIDEAE. Trade and local names: akasia, mangium (ID, MY). Not protected under CITES regulations.

Description based on 2 specimens. Tree. Geographic distribution: Thailand, Laos, Vietnam, Cambodia to Australia.

General. Growth ring boundaries indistinct or absent. Growth rings macroscopically visible in wood from certain provenances (e.g. Thailand). Heartwood basically light golden to olive brown, with streaks or without streaks. Sapwood colour distinct from heartwood colour. Density 0.4–0.5 g/cm³. Wood of commercial potential (mainly from plantations).

Vessels. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows. Average tangential vessel diameter 120–160 µm. Average number of vessels/mm² 4–9. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 6–9 µm, vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent. Tyloses in vessels absent. Other deposits in heartwood vessels not observed.

Tracheids and fibres. Fibres very thin-walled and of medium wall thickness. Average fibre length 900–1300 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate.

Axial parenchyma. Axial parenchyma not banded. Axial parenchyma paratracheal. Paratracheal axial parenchyma vasicentric. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 2–4.

Rays. Rays 4–8 per tangential mm, multiseriate (also if only few), 1–3 cells wide. Rays composed of a single cell type (homocellular); homocellular ray cells procumbent.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells absent. Intercellular canals absent. Laticifers or tanniniferous tubes 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 fluorescent (yellow).

Illustrations. • Transverse section. Acacia mangium. • Tangential section. Acacia mangium. • Radial section. Acacia mangium.

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.’.