Commercial Timbers


H. G. Richter and M. J. Dallwitz

Palaquium spp. (Nyatoh)

Nomenclature etc. SAPOTACEAE. According to Malaysian Grading Rules the following species: Palaquium hexandrum, P. hispidum, P. impressinervium, P. maingayi, P. obovatum, P. regina-montium, P. semaram, P. sumatranum, P. walsurifolium, Palaquium spp. Trade and local names: nyatoh (MY, ID, DE); chay (VN); pencil cedar, red planchonella (PG); pali (IN); nato (PH); kha-nunnok (TH); riam, jangka (MY-sar); hangkang, balam teruing puteh, balam masin, kayu tanjung hutan, mayang, taban (MY, ID); moordooke (AU). Not protected under CITES regulations.

Tree. Geographic distribution: Indomalesia and Pacific Islands.

General. Heartwood basically brown to red. Sapwood colour distinct from heartwood colour. Density 0.4–0.65 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in diagonal and/or radial pattern or no specific pattern, in multiples, commonly short (2–3 vessels) radial rows or radial rows of 4 or more. Average tangential vessel diameter 60–150–270 µm. Average number of vessels/mm² 3–8–13(–40). Average vessel element length 440–900–1250 µm. Perforation plates simple or scalariform, with 3–10 bars. Intervessel pits alternate, average diameter (vertical) 4–8 µm. Vessel-ray pits with distinct borders or with reduced borders or apparently simple, similar to intervessel pits or different from intervessel pits, horizontal to vertical, of two distinct sizes or types in the same ray cell. Tyloses in vessels present, thinwalled.

Tracheids and fibres. Vascular or vasicentric tracheids commonly present. Fibres very thin-walled, or of medium wall thickness. Average fibre length 1300–1760–2310 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered.

Axial parenchyma. Axial parenchyma present, banded. Axial parenchyma bands marginal (or seemingly marginal), reticulate, fine, up to three cells wide, (3–)6(–12) per radial mm. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–12.

Rays. Rays 8–12 per tangential mm, multiseriate (also if only few), 1–3 cells wide. 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 or with more than 4 marginal rows of upright or square cells. Disjunctive ray parenchyma end walls indistinct or absent.

Storied structures. Storied structure 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.

Illustrations. • Transverse section. Palaquium hexandrum. • Tangential section. Palaquium obovatum. • Radial section. Palaquium hexandrum. • Crystals in axial parenchyma. Palaquium sumatranum. Prismatic crystals in chambered parenchyma cells (semi-polarized light).

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.’.