Commercial Timbers


H. G. Richter and M. J. Dallwitz

Entandrophragma utile (Dawe & Sprague) Sprague (Sipo, utile)

Nomenclature etc. MELIACEAE. Syn.: Entandrophragma macrocarpa A. Chev., E. roburoides Vermoesen, E. thomasii Ledoux. Trade and local names: sipo (DE, CI, FR); assié (FR, CM); utile (DE, GH, GB); bada, mébrou, zuiri (CI); assi, ombolobolo, mouragalamando, kos-kosi (GA); efou-konkonti (GH); muyoyu (UG); timbi, assang-assié (CM); kalungi, m'vovo, tshimai rouge/noir (CD); akuk, ogipogo, ubilesan (NG); momboyo (CG); njeli (LR). Not protected under CITES regulations.

Tree. Geographic distribution: tropical Africa.

General. Growth ring boundaries distinct. Heartwood basically brown to red brown to yellow (upon exposure), without streaks. Sapwood colour distinct from heartwood colour. Odour indistinct or absent. Density 0.45–0.59–0.7 g/cm³.

Vessels. Wood diffuse-porous. Vessels in multiples, commonly short (2–3 vessels) radial rows. Average tangential vessel diameter 140–230–295 µm; diameter of vessel lumina: large. Average number of vessels/mm² 3–6; vessels per square millimetre very few to few. Average vessel element length 500–650 µm. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 2–4 µm. Vessel-ray pits with distinct borders (though difficult to perceive), similar to intervessel pits. Helical thickenings absent. Tyloses in vessels absent. Other deposits in heartwood vessels present (dark reddish brown).

Tracheids and fibres. Fibres of medium wall thickness. Average fibre length 830–1440–2060 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres exclusively septate to septate and non-septate. Septate fibres evenly distributed. 1–4 septa per fibre.

Axial parenchyma. Axial parenchyma banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide. Axial parenchyma apotracheal, or paratracheal (short wavy bands often without contact to vessels). Paratracheal axial parenchyma scanty, vasicentric, and confluent. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 7–8.

Rays. Rays (2–)5–7 per tangential mm, multiseriate (also if only few), 2(–4) cells wide. Rays composed of a single cell type (homocellular), or two or more cell types (heterocellular); homocellular ray cells procumbent. Heterocellular rays with square and upright cells restricted to marginal rows, mostly 1 marginal row of upright or square cells and mostly 2–4 marginal rows of upright or square cells (rarely). Tile cells absent.

Storied structures. Storied structure present or absent, all rays storied, axial parenchyma not storied, vessel elements not storied. Arrangement of tiers regular (horizontal or straight), or irregular. Number of ray tiers per axial millimetre 2.

Secretory structures. Intercellular canals present or absent, traumatic origin, axial type, in short tangential lines. 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, or not chambered. Number of crystals per cell or chamber one. Silica not observed.

Illustrations. • Macro images. Entandrophragma utile. Transverse. Radial. • Transverse section. Entandrophragma utile. • Tangential section. Entandrophragma utile. • Radial section. Entandrophragma utile.

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: 25th June 2009.’.