Commercial Timbers


H. G. Richter and M. J. Dallwitz

Ctenolophon parvifolius Oliv. (Mertas)

Nomenclature etc. LINACEAE. Trade and local names: mertas (trade); adau (BN); kalek bung cung, kayu bawang, latak manuk (ID); besi besi, litoh (MY); ctenoöophon (PG); sudiang (PH). Not protected under CITES regulations.

Description based on 1 specimen. Tree. Geographic distribution: Indomalesia and tropical South America.

General. Growth ring boundaries indistinct or absent. Heartwood basically brown (brown to purple greyish brown), without streaks. Sapwood colour similar to heartwood colour, or distinct from heartwood colour. Odour indistinct or absent. Density 0.8–1.1 g/cm³. Wood of commercial potential.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary. Vessel outline angular. Two distinct vessel diameter classes absent. Average tangential vessel diameter 105–120–150 µm; diameter of vessel lumina: large. Average number of vessels/mm² 16; vessels per square millimetre few. Perforation plates scalariform, with up to 20 bars. Vessel-ray pits with distinct borders or with reduced borders or apparently simple, different from intervessel pits, of uniform size or type, unilaterally compound and coarse, located throughout the ray. Helical thickenings absent. Tyloses in vessels present, thinwalled. Other deposits in heartwood vessels not observed.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thick-walled. Fibre pits common in both radial and tangential walls, distinctly bordered. Helical thickenings absent. Fibres non-septate.

Axial parenchyma. Axial parenchyma present, not banded. Axial parenchyma paratracheal. Paratracheal axial parenchyma unilateral. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 5–8. Unlignified parenchyma absent.

Rays. Rays present, 8–9 per tangential mm, multiseriate (also if only few), 1–3 cells wide, narrow (2–3 seriate). Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of one size. 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 and with more than 4 marginal rows 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, located in ray cells and axial parenchyma cells. Crystal-containing ray cells upright and/or square and procumbent, upright and/or square ray cells chambered and not chambered. Crystals in procumbent ray cells not in radial alignment. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Crystal containing cells of normal size. Cystoliths absent. Silica not observed.

Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; basically colourless to brown or shade of brown. Heartwood extractives not leachable by water. Ethanol extract fluorescent (light green). Colour of ethanol extract colourless to brown or shade of brown. Chrome azurol-S test negative. Froth test negative. Splinter burns to partial ash. Ash other than white, grey, yellow or brown.

Illustrations. • Transverse section. Ctenolophon parvifolius. • Tangential section. Ctenolophon parvifolius. • Radial section. Ctenolophon parvifolius. • Miscellaneous-1. Ctenolophon parvifolius. Note: Scalariform perforation plates (SP) and prismatic crystals in chambered axial parenchyma cells (C). SP. C. SP. • Miscellaneous-2. Ctenolophon parvifolius. Note: Prismatic crystals in chambered marginal ray cells (C) and compound vessel-ray pit fields (PF). C. PF.

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.’.