Commercial Timbers


H. G. Richter and M. J. Dallwitz

Elmerrillia spp. (Chempaka, wau beech)

Nomenclature etc. MAGNOLIACEAE. Species included in the description: Elmerrillia mollis Dandy (4), Elmerrillia ovalis (Miq.) Dandy (8), Elmerrillia papuana Dandy (3), Elmerrillia pubescens (Merr.) Dandy (1), Elmerrillia tsiampaca (L.) Dandy (1). Not protected under CITES regulations.

Description based on 17 specimens. Tree. Geographic distribution: India, Pakistan, Sri Lanka, Burma, Thailand, Laos, Vietnam, Cambodia, and Indomalesia.

General. Growth ring boundaries distinct. Growth ring boundaries demarcated by marginal parenchyma bands. Heartwood basically yellow and white or grey, without streaks. Sapwood colour distinct from heartwood colour. Odour indistinct or absent.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows, radial rows of 4 or more, and in clusters. Vessel outline rounded and angular. Two distinct vessel diameter classes absent. Average tangential vessel diameter 60–130–200 µm; diameter of vessel lumina: medium and large. Average number of vessels/mm² 8–20; vessels per square millimetre few. Perforation plates scalariform, with 1–7 bars. Intervessel pits scalariform, average diameter (vertical) 8–10 µm, medium, not vestured. Vessel-ray pits with reduced borders or apparently simple, rounded or angular and horizontal to vertical, 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 not observed.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thin-walled. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Helical thickenings absent. Fibres non-septate. Fibre pits inconspicuously bordered.

Axial parenchyma. Axial parenchyma present, banded. Axial parenchyma bands marginal (or seemingly marginal), bands much wider than rays, coarse, more than three cells wide. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–6–8. Unlignified parenchyma absent. Axial parenchyma with oil cells.

Rays. Rays present, 4–6 per tangential mm, multiseriate (also if only few), (1–)2–4 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 up to 500 µm and 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 and mostly 2–4 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. Oil cells in marginal rows of rays.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells present, associated with axial parenchyma and ray parenchyma. Oil cells not observed in two specimens of E. ovalis. Intercellular canals absent. Laticifers or tanniniferous tubes absent.

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

Mineral inclusions. Crystals not observed. Silica present (only in some specimens), as vitreous silica, in vessels.

Physical and chemical tests. Heartwood not fluorescent. Water extract fluorescent; basically colourless to brown or shade of brown. Heartwood extractives not leachable by water. Ethanol extract fluorescent. 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 white to grey.

Illustrations. • Transverse section. Elmerrillia papuana. • Tangential section. Elmerrillia papuana. • Radial section. Elmerrillia papuana. • Vitreous silica in vessels. Elmerrillia ovalis. Vitreous silica (VSi) in vessels of some specimens. VSi.

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.’.