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| Commercial timbers |
Nomenclature etc. FABACEAE-FABOIDEAE. Trade and local names: granadillo (MX); hormigón (GT); macawood (BR); roble (VE). Not protected under CITES regulations.
Description based on 5 specimens. Tree. Geographic distribution: Mexico and Central America, tropical South America.
General. Growth ring boundaries distinct (demarcated by very narrow marginal parenchyma bands). Heartwood basically red (bright red to reddish or purplish brown); with streaks. Sapwood colour similar to heartwood colour, or distinct from heartwood colour (whitish). Odour indistinct or absent. Density 0.75–0.9 g/cm³.
Vessels. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 60–180 µm. Average number of vessels/mm² 4–12. Average vessel element length 150–410 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 6–10 µm, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent. Other deposits present (yellowish).
Tracheids and fibres. Fibres very thick-walled. Average fibre length 670–1200 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered.
Axial parenchyma. Axial parenchyma banded. Bands marginal (or seemingly marginal). Bands fine. Axial parenchyma paratracheal. Paratracheal axial parenchyma aliform, or confluent. Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 2.
Rays. Rays 12–15 per tangential mm, exclusively uniseriate. Height of large rays up to 500 µm. Rays composed of a single cell type (homocellular); homocellular ray cells procumbent.
Storied structures. Storied structure present, all rays storied, axial parenchyma storied, vessel elements storied, fibres storied or not storied. Arrangement of tiers regular, or irregular. Number of ray tiers per axial millimetre 4.
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, or not fluorescent (occasionally weakly fluorescent yellow). Water extract fluorescent (blue); colour of water extract colourless to brown. Ethanol extract fluorescent (dark blue). Colour of ethanol extract colourless to brown to red. Froth test positive, or negative.
Illustrations. • Transverse section. • Tangential section. storeying of rays regular in some specimens (left), hardly evident in others (right). • 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’.
