Commercial Timbers


H. G. Richter and M. J. Dallwitz

Canarium schweinfurthii Engl. (Aielé)

Nomenclature etc. MMSERACEAE. C. schweinfurthii Engl. - Syn.: C. chevalieri Guillaum., C. occidentale A. Chev., C. velutinum Guillaum.; similar: C. euphyllum, C. sikkimense, C. aspersum, etc. Trade and local names: aiélé (DE, FR, CI, GH, GA, BE), canarium (DE, GB, BE, NG), m'bili (AO, CG, LR), African canarium (GB, NG), bidikala, bidinkala, mbidikala (BE, CD), ahie, labe (CI), abel, abeul, ovili (GA), bediwunua (GH), olem (GQ), atué, botua, wotua (CM), goekwehn (LR), elimi, ibagho (NG), m'wafu (UG), bobele, mubiri, mupafu (CD). Not protected under CITES regulations.

Tree. Geographic distribution: tropical Africa.

General. Heartwood basically yellow to white or grey (yellowish to pinkish grey). Sapwood colour similar to heartwood colour. Density 0.33–0.46–0.53 g/cm³. Frequently with interlocked grain.

Vessels. Wood diffuse-porous. Vessels in multiples, commonly short (2–3 vessels) radial rows. Average tangential vessel diameter 170–220–255 µm. Average number of vessels/mm² 2–4–5. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 10–13 µm, not vestured. Vessel-ray pits with reduced borders or apparently simple, rounded or angular or horizontal to vertical, of uniform size or type (same type but of different sizes), of the same type in adjacent elements (rarely unilaterally compound). Tyloses in vessels present, thinwalled.

Tracheids and fibres. Fibres very thin-walled. Average fibre length 990–1185–1415 µm. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Fibres exclusively septate. Septate fibres evenly distributed.

Axial parenchyma. Axial parenchyma not banded. Axial parenchyma apotracheal and paratracheal (apotracheal parenchyma very rare). Apotracheal axial parenchyma diffuse. Paratracheal axial parenchyma scanty to vasicentric. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 4–6–8.

Rays. Rays multiseriate (also if only few), (1–)2–3 cells wide. Rays composed of a single cell type (homocellular) (rare), 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 to mostly 2–4 marginal rows of upright or square cells.

Storied structures. Storied structure present or absent (in most specimens rather indistinct), all rays storied. Arrangement of tiers regular (horizontal or straight) to irregular.

Secretory structures. Intercellular canals absent. Laticifers or tanniniferous tubes absent.

Mineral inclusions. Crystals present, prismatic or druses or in other forms, located in ray cells or axial parenchyma cells. Crystal-containing ray cells upright and/or square or procumbent. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one (refers to prismatic crystals only). Spherical crystalline splinters distributed over the entire ray, partly also druses present; true prismatic crystals and small splinters primarily in marginal rows, occasionally together with silica particles. Silica present, as grains, in rays cells (mostly but not exclusively restricted to marginal upright cells) or in axial parenchyma (rare) or in fibres (rare). According to literature the occurrence and type of silica in Canarium species is extremely variable.

Illustrations. • Transverse section. Canarium schweinfurthii. • Tangential section. Canarium schweinfurthii. • Radial section. Canarium schweinfurthii. • Silica particles. Canarium schweinfurthii -- silica particles in marginal ray cells. • Silica particles + crystals. Canarium schweinfurthii -- silica particles (SI) and prismatic crystals (CR) in marginal ray cells, rarely jointly in a single cell (C+S). C+S. CR. SI.

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.’.