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| Commercial timbers |
Nomenclature etc. DIPTEROCARPACEAE. Syn.: Balanocarpus heimii King, B. wrayi King, B. accuminatus Heim. Trade and local names: chengal (DE, GB, NL, MY), chingal, penak (MY), takien chan (TH). Not protected under CITES regulations.
Tree. Geographic distribution: Indomalesia (Malay peninsula).
General. Heartwood basically yellow to brown, red to brown, green to brown (yellowish brown when fresh, darkening to olive or red brown); without streaks. Sapwood colour distinct from heartwood colour. Density 0.7–0.8 g/cm³.
Vessels. Wood diffuse porous. Vessels exclusively solitary or in multiples (in some specimens with few pore groups), commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 105–155–210 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 4–6 µm, pits vestured. Vessel-ray pits with reduced borders or apparently simple, different from intervessel pits, rounded or angular, of uniform size or type (same type in different sizes). Vessel-parenchyma pits often scalariform. Tyloses present (frequent), thinwalled.
Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres of medium wall thickness to very thick-walled. Fibre pits mainly restricted to radial walls, distinctly bordered.
Axial parenchyma. Axial parenchyma banded (axial resin canals enclosed in parenchyma bands) or not banded. Axial parenchyma bands much wider than rays. Bands coarse. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse and diffuse-in-aggregates. Paratracheal axial parenchyma vasicentric, aliform, confluent, and unilateral (predominantly unilateral, always fine). Aliform parenchyma of the winged type. Axial parenchyma as strands. Average number of cells per strand: 2–4(–6).
Rays. Rays multiseriate, (1–)3–5 cells wide. 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 1 marginal row of upright or square cells or mostly 2–4 marginal rows of upright or square cells or with more than 4 marginal rows of upright or square cells. Sheath cells present.
Storied structures. Storied structure present, all rays storied, axial parenchyma storied, vessel elements storied.
Secretory structures. Intercellular canals present, oriented axially, axial intercellular canals in long tangential lines or in short tangential lines.
Mineral inclusions. Crystals present, prismatic, located in ray cells. Crystal-containing ray cells upright and/or square and procumbent. Crystals in procumbent ray cells not in radial alignment. Number of crystals per cell or chamber one. Silica not observed.
Illustrations. • Transverse section. axial intercellular canals (IC) in tangential bands. IC. • 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’.
