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| Commercial timbers |
Nomenclature etc. FABACEAE-FABOIDEAE. Trade and local names: beantree, Moreton Bay-bean (AU); Australian chestnut (GB). Not protected under CITES regulations.
Description based on 4 specimens. Tree. Geographic distribution: Australia.
General. Growth ring boundaries distinct (if distinct, demarcated by marginal parenchyma bands) or indistinct or absent. Heartwood basically brown; with streaks. Sapwood colour distinct from heartwood colour (almost white to yellowish). Density 0.75–0.81 g/cm³.
Vessels. Vessels present. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows or in radial rows of 4 or more. Average tangential vessel diameter 80–180–280 µm. Average number of vessels/mm² 3–6. 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. Tyloses absent. Other deposits present (brown).
Tracheids and fibres. Fibres of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate.
Axial parenchyma. Axial parenchyma banded and not banded. Bands marginal (or seemingly marginal) (rarely distinct). Bands fine. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse (individual strands of chambered, crystalliferous cells). Paratracheal axial parenchyma aliform and confluent. Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 3–6.
Rays. Rays 8–11 per tangential mm, multiseriate, (1–)2–3 cells wide. 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.
Storied structures. Storied structure present or absent, all rays storied, axial parenchyma not storied. Arrangement of tiers irregular. Number of ray tiers per axial millimetre 2–3. Rays occasionally with a tendency towards storied arrangement.
Secretory structures. Intercellular canals absent. Laticifers or tanniniferous tubes absent.
Cambial variants. Included phloem 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 not fluorescent. Water extract fluorescent (orange); colour of water extract colourless to brown. Ethanol extract fluorescent (violet). Colour of ethanol extract colourless to brown. Froth test positive. Splinter burns to partial ash. Ash white to grey.
Illustrations. • Transverse section. • 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’.
