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Nomenclature etc. MALVACEAE (STERCULIACEAE). Syn. Eribroma oblonga (Mast.) Bodard. Trade and local names: Yellow Sterculia, white Sterculia (GB, NG); azodo, bi (CI); njong (GA); n'chong (GQ); bongele, ekonge, lom, moan (CM); ebenebe, kokoniko, okoko, orodo (NG); bongo (CD). Not protected under CITES regulations.
Description based on 8 specimens. Tree. Geographic distribution: tropical Africa (West-).
General. Heartwood basically cream coloured to yellow. Sapwood colour similar to heartwood colour. Density 0.7–0.8 g/cm³.
Vessels. Wood diffuse porous. Vessels in multiples, commonly in short (2–3 vessels) radial rows. Average tangential vessel diameter (100–)210(–270) µm. Average number of vessels/mm² 2–7. Average vessel element length 400–500 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 4–6 µm. Vessel-ray pits with distinct borders, similar to intervessel pits. Tyloses absent. Other deposits present (honey to amber coloured).
Tracheids and fibres. Fibres of medium wall thickness to very thick-walled. Average fibre length (1600–)1970(–2250) µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered.
Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands much wider than rays. Bands coarse (up to 15 cells). Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse-in-aggregates. Paratracheal axial parenchyma aliform, or confluent. Aliform parenchyma of the lozenge type. Axial parenchyma as strands. Average number of cells per strand: 4–5.
Rays. Rays 2–4 per tangential mm, multiseriate, 3–15 cells wide. Height of large rays commonly 500 to 1000 µm, or commonly over 1000 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. Sheath cells present.
Storied structures. Storied structure present, rays not storied, axial parenchyma storied, vessel elements storied, fibres storied. Number of ray tiers per axial millimetre 2–3.
Secretory structures. Intercellular canals present, traumatic origin (exclusively), oriented axially, axial intercellular canals in short tangential lines.
Mineral inclusions. Crystals present, prismatic, located in ray cells and axial parenchyma cells. Crystal-containing ray cells upright and/or square (in sheath cells). Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. The cristalliferous chambered parenchyma strands are few and relatively short in the inner regios of the bands whereas those adjacent to the fibrous tissue can be very long and numerous. Silica not observed.
Physical and chemical tests. Heartwood not fluorescent. Water extract not fluorescent; colour of water extract colourless to brown. Ethanol extract not fluorescent. Colour of ethanol extract colourless to brown. Splinter burns to full ash, or to partial ash. Ash white to grey.
Illustrations. • Transverse section. • Tangential section. • Radial section. « chains of crystalliferous chambered parenchyma cells (left) along the parenchyma-fibre interface. • Traumatic intercellular canals. Sterculia oblonga. traumatic intercellular canals (TrC). TrC.
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’.
