Commercial Timbers


H. G. Richter and M. J. Dallwitz

Dryobalanops spp. (Kapur)

Nomenclature etc. DIPTEROCARPACEAE. + D. sumatrensis (J.F. Gmelin) Kosterm. (Syn.: D. aromatica) Gaertn.f.; D. oblongifolia Dyer; D. lanceolata Burck; D. camphora Colebr., D. junghunii Becc., D. kayanensis Becc. Trade and local names: kapur paji, k. bukit, tepurau, sintok, amplang, oewa, padji (Borneo), Oost-Borneo kamfer (NL), kapur, North Borneo kapur, Borneo camphorwood (GB), kapur, keladan (MY). Not protected under CITES regulations.

Tree. Geographic distribution: Indomalesia.

General. Growth ring boundaries indistinct or absent. Heartwood basically brown to red, without streaks. Sapwood colour distinct from heartwood colour. Odour distinct (D. aromatica only). Density 0.58–0.8 g/cm³.

Vessels. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary. Average tangential vessel diameter 140–200–260 µm; diameter of vessel lumina: large, or very large. Average number of vessels/mm² 5–17; vessels per square millimetre few. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm, small, not vestured. Vessel-ray pits with reduced borders or apparently simple, similar to intervessel pits or different from intervessel pits, of uniform size or type, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses in vessels present, thinwalled. Other deposits in heartwood vessels present (brown).

Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres of medium wall thickness. Fibre pits common in both radial and tangential walls, distinctly bordered. Fibres non-septate.

Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands not marginal (or seemingly marginal). Axial parenchyma apotracheal and paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma scanty, aliform, and confluent. Aliform parenchyma lozenge and winged. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–6(–8).

Rays. Rays 4–6(–8) per tangential mm, multiseriate (also if only few), 3–4(–6) cells wide, of medium width (3–5 seriate). Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of two distinct sizes. Height of large rays commonly 500 to 1000 µm. Rays composed of two or more cell types (heterocellular). Heterocellular rays with square and upright cells restricted to marginal rows, mostly 2–4 marginal rows of upright or square cells.

Storied structures. Storied structure present or absent, all rays storied (only D. aromatica), axial parenchyma storied (only D. aromatica). Arrangement of tiers regular (horizontal or straight), or irregular. Number of ray tiers per axial millimetre 1–2.

Secretory structures. Intercellular canals present, non-traumatic origin, axial type, in long tangential lines.

Mineral inclusions. Crystals present (D. keithii, D. lanceolata, D. oblongifolia, D. rappa) or not observed, prismatic, located in axial parenchyma cells. Crystal-containing axial parenchyma cells not chambered. Number of crystals per cell or chamber one. Crystal containing cells of normal size. Silica present, as grains, in rays cells and in axial parenchyma (rare, in D. oocarpa, D. oblongifolia).

Physical and chemical tests. Heartwood not fluorescent. Water extract basically colourless to brown or shade of brown (brown). Heartwood extractives leaching out when in contact with water. Splinter burns to charcoal.

Illustrations. • Macro images. Dryobalanops aromatica. Transverse. Longitudinal. • Transverse section. Dryobalanops aromatica. Note axial intercellular canals (ICb) in tangential bands. ICb. • Tangential section 1. Dryobalanops aromatica. • Tangential section 2. Dryobalanops beccarii. • Radial section. Dryobalanops beccarii. • Silica in rays. Dryobalanops beccarii. Silica paticles in ray cells.

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.’.