Commercial Timbers


H. G. Richter and M. J. Dallwitz

Mesua ferrea L. (Penaga)

Nomenclature etc. GUTTIFERAE. Trade and local names: penaga (MY). Not protected under CITES regulations.

Description based on 4 specimens. Geographic distribution: Thailand, Laos, Vietnam, Cambodia.

General. Growth ring boundaries indistinct or absent. Heartwood basically brown and red (red-brown), without streaks. Sapwood colour distinct from heartwood colour. Odour indistinct or absent. Density 0.94–1.13 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in diagonal and/or radial pattern, exclusively solitary. Vessel outline rounded. Two distinct vessel diameter classes absent. Average tangential vessel diameter 100–150–200 µm; diameter of vessel lumina: large. Average number of vessels/mm² 4–6; vessels per square millimetre very few. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 4–7 µm (pits only between vasicentric tracheids and vessels), small. Vessel-ray pits with reduced borders or apparently simple, rounded or angular and horizontal to vertical, of two distinct sizes or types in the same ray cell, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses in vessels present, thinwalled and sclerotic. Other deposits in heartwood vessels present, red-brown.

Tracheids and fibres. Vascular or vasicentric tracheids commonly present (vasicentric tracheids). Fibres very thick-walled. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Helical thickenings absent. Fibres non-septate. Ocasionally with helical thickenings in vasicentric tracheids.

Axial parenchyma. Axial parenchyma present, banded and not banded. Axial parenchyma bands not marginal (or seemingly marginal), bands much wider than rays, fine, up to three cells wide. Axial parenchyma apotracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 6–11. Parenchyma bands wavy.

Rays. Rays present, 9–13 per tangential mm, exclusively uniseriate. Aggregate rays absent. Rays of one size. Height of large rays up to 500 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 (rarely 2). Tile cells absent. Perforated ray cells absent. Disjunctive ray parenchyma end walls indistinct or absent. Occasionally also bi-seriate rays.

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 axial parenchyma cells. 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 fluorescent (purple); basically colourless to brown or shade of brown. Heartwood extractives not leachable by water. Ethanol extract fluorescent (pinkish). Colour of ethanol extract red or shade of red. Ethanol extract orange. Chrome azurol-S test negative. Froth test negative. Splinter burns to partial ash. Ash yellow-brown.

Illustrations. • Transverse section. Mesua ferrea. • Tangential section. Mesua ferrea. • Radial section. Mesua ferrea.

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.’.