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| Commercial timbers |
Nomenclature etc. FABACEAE-FABOIDEAE. Syn.: Tipuana speciosa Benth., Machaerium tipu Benth. Trade and local names: tipa (AR); tipa branca (BR). Not protected under CITES regulations.
Description based on 4 specimens. Tree. Geographic distribution: southern Brazil, temperate South America.
General. Growth ring boundaries distinct. Heartwood basically yellow, white or grey; without streaks. Sapwood colour similar to heartwood colour. Density 0.67–0.75 g/cm³. Wood of commercial potential.
Vessels. Wood semi ring porous or diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter 130–150 µm (latewood 30–80 µm, earlywood up to 300 µm); diameter of vessels: large. Average number of vessels/mm² 6–15; vessels per square millimetre few. Average vessel element length 200–300 µm. Average vessel element length short. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm, average diameter (vertical) small, pits vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent. Tyloses absent. Other deposits present (scarce, colour of amber).
Tracheids and fibres. Fibres very thin-walled to of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Helical thickenings absent. Fibres non-septate.
Axial parenchyma. Axial parenchyma present, banded. Bands marginal (or seemingly marginal). Bands fine. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma aliform, or confluent. Aliform parenchyma of the winged type. Axial parenchyma fusiform (mostly 2-celled).
Rays. Rays 12–16 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. Arrangement of tiers regular. Number of ray tiers per axial millimetre 4–6.
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. Froth test negative.
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’.
