Commercial Timbers


H. G. Richter and M. J. Dallwitz

Duabanga moluccana Blume (Duabanga)

Nomenclature etc. SONNERATIACEAE. + Duabanga grandiflora (Roxb. ex DC.) Walp (Syn.: D. sonneratioides Buch.-Ham.). Trade and local names: binuang, benuang, b. laki, gayawas hutan, kalanggo (ID); magasawih, berembang bukit, magas (MY); loktob (PH); myaukngo (MM); dlom chloeu ter (KH); phay (LA); lamphu-pa, tum-ten, lamphaen (TH). Not protected under CITES regulations.

Tree. Geographic distribution: Burma to Indomalesia.

General. Growth ring boundaries indistinct or absent. Heartwood basically white or grey, without streaks. Sapwood colour similar to heartwood colour. Odour indistinct or absent. Density 0.25–0.52 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows. Average tangential vessel diameter 160–250(–350) µm. Average number of vessels/mm² 2–7. Average vessel element length 700–800 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 8–12 µm, vestured. Vessel-ray pits with reduced borders or apparently simple, rounded or angular or horizontal to vertical, of the same type in adjacent elements or unilaterally compound and coarse. Helical thickenings absent. Tyloses in vessels present, thinwalled.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thin-walled, or of medium wall thickness. Average fibre length 1200–1400(–2300) 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 scanty, or vasicentric. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 3–7.

Rays. Rays 8–10 per tangential mm, exclusively uniseriate or multiseriate (also if only few), 1(–2) cells wide. Rays composed of a single cell type (homocellular), or two or more cell types (heterocellular); homocellular ray cells procumbent. Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells. Sheath cells absent. Tile cells absent. Perforated ray cells absent. Disjunctive ray parenchyma end walls indistinct or absent.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells absent. Intercellular canals absent. Laticifers or tanniniferous tubes absent.

Cambial variants. Included phloem absent. Other cambial variants absent.

Mineral inclusions. Crystals present, prismatic and styloids or elongate, located in ray cells or axial parenchyma cells. Crystal-containing ray cells upright and/or square. Crystal-containing axial parenchyma cells not chambered. Number of crystals per cell or chamber one, or more than one. Crystals in one cell or chamber of two distinct sizes. Crystal containing cells of normal size. Cystoliths absent. Silica not observed.

Illustrations. • Transverse section. Duabanga moluccana. • Tangential section. Duabanga moluccana. • Radial section. Duabanga moluccana. Note crystals in axial parenchyma (blow-up in next picture). • Crystals in axial parenchyma. Duabanga moluccana. Prismatic crystals of different size and variable number per cell in axial parenchyma.

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.’.