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| Commercial timbers |
Nomenclature etc. FABACEAE-FABOIDEAE. The following Dalbergia timbers from Madagascar have a similar structure: D. perrieri, D. purpurascens, D. mollis, D. trichocarpa. Trade and local names: Madagaskar Palisander (DE); Madagascar rosewood (trade); palissandre violet, p. de Masagascar (FR). Listed in CITES Annex II.
Description based on 4 specimens. Tree. Geographic distribution: western Madagascar & other islands.
General. Growth ring boundaries distinct. Heartwood basically brown, purple; with streaks. Sapwood colour distinct from heartwood colour. Density 0.85–1.05 g/cm³.
Vessels. Vessels present. Wood ring porous or semi ring porous (growth ring limits demarcated by uniseriate, generally discontinuous rings of large earlywood pores). Ring of earlywood vessels uniseriate. Vessels arranged in no specific pattern, in multiples, commonly in short (2–3 vessels) radial rows. Average tangential diameter of vessels: medium (latewood), or very large (earlywood). Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 7–9 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent. Other deposits present.
Tracheids and fibres. Fibres of medium wall thickness to very thick-walled. Fibre pits mainly restricted to radial walls, simple to minutely bordered.
Axial parenchyma. Axial parenchyma banded or not banded. Bands marginal (or seemingly marginal) or not marginal (or seemingly marginal). Bands fine. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma aliform, or confluent, or unilateral. Aliform parenchyma of the lozenge type. Axial parenchyma fusiform, or as strands. Average number of cells per strand: 2.
Rays. Rays 8–10 per tangential mm, multiseriate, 1–2 cells wide. Height of large rays up to 500 µm. Rays composed of a single cell type (homocellular) and two or more cell types (heterocellular) (very inconspicuous); homocellular ray cells procumbent. Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells. Sheath cells absent.
Storied structures. Storied structure present, all rays storied, axial parenchyma storied, vessel elements storied, fibres storied. Arrangement of tiers regular, or irregular. Number of ray tiers per axial millimetre 6.
Secretory structures. Intercellular canals 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.
Physical and chemical tests. Heartwood fluorescent (weakly yellow), or not fluorescent. Water extract not fluorescent; colour of water extract colourless to brown. Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown, or red. Froth test positive. Splinter burns to full ash. Ash white to grey.
Illustrations. • Macroscopic images. transverse (ca. 10x). radial (natural size). • Transverse section 1. earlywood pore rings more or less continuous. • Transverse section 2. earlywood pore rings discontinuous. • 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’.
