Tetraberlinia bifoliolata, T. tubmanniana (Ekaba)
Nomenclature etc. CAESALPINIACEAE. Syn.: Berlinia bifoliolata Harms. Trade and local names: ekaba (GQ, E, trade); hoh, sikon, gola (LB); ekop, ekop-ribi (CAM); eko-andoung (G); tetraberlinia (GB).
Tree. Geographic distribution: tropical Africa.
General. Growth ring boundaries distinct or indistinct or absent, growth ring limits marked by darker latewood zones límites de anillos de crecimiento marcados por zonas oscuras de madera tardía. Heartwood without streaks. Sapwood colour distinct from heartwood colour. Basic specific gravity 0.52–0.66 g/cm³.
Vessels. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows. Average tangential vessel diameter 150–250 µm. Average number of vessels/mm² 3–6. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 5–7 µm, vestured. Vessel-ray pits with distinct borders, similar to intervessel pits. Other deposits in heartwood vessels occasionally present.
Tracheids and fibres. Fibres very thin-walled, or of medium wall thickness. Average fibre length 700–1700 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres non-septate. Fibre fractional volume ca. 65% fracción volumétrica de fibras ca. 65%.
Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide or coarse, more than three cells wide. Axial parenchyma paratracheal. Paratracheal axial parenchyma vasicentric, or aliform. Aliform parenchyma lozenge. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–8.
Rays. Rays 8–15 per tangential mm, exclusively uniseriate. Rays composed of two or more cell types. Heterocellular rays square and upright cells restricted to marginal rows. Number of marginal rows of upright or square cells 1.
Storied structures. Storied structure present, all rays storied, axial parenchyma not storied. Arrangement of tiers irregular. Storied rays only sporadically and in irregular strata in T. tubmanniana.
Secretory structures. Intercellular canals present, traumatic origin, axial type, in long tangential lines or in short tangential lines.
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.
Cite this publication as: H. G. Richter and M. J. Dallwitz (2000 onwards). 'Commercial timbers: descriptions, illustrations, identification, and information retrieval.' In English, French, German, and Spanish. Version: 4th May 2000. http://biodiversity.uno.edu/delta/.
Dallwitz (1980) and Dallwitz, Paine and Zurcher (1993 onwards, 1995 onwards, 1998) should also be cited (see General references).