Schweinfurth's Olive

Canarium schweinfurthii Engler

Standard trade name: Canarium

Local names: Bediwunua (Ghana), Abel (French West Africa), Elemi (Nigeria)

An evergreen and deciduous forest tree growing to 120–160 ft high and 12–15 ft in girth. Although the trees are not very common, they can be found in the high forest zone and in the savanna-woodland. They are often located in the Antiaris-Chlorophora association. The leaves are pinnate, oblong or oblong-lanceolate, acuminate, generally in terminal whorls. The flowers are creamy white and are borne in axillary panicles.

GENERAL DESCRIPTION.—The sapwood is whitish, up to 3–4 in; the heartwood is pale pink darkening to light brown. The surface is highly lustrous and the wood is highly scented, especially when it is freshly cut. The texture is somewhat coarse and sometimes may appear woolly. The grain is often interlocked. The wood is light to medium, weighing 31–38 lb/ft3 averaging 33 lb/ft3 when seasoned.

SEASONING.—This wood dries quite easily either when air seasoned or kiln dried. Because of a tendency to warp, it is recommended that initial exposure should be at low temperatures.

DURABILITY.—The wood is not very durable since it is easily attacked by pinhole borers and powder-post beetles. It is very resistant to impregnation, especially the heartwood by the open-process, but the sapwood is fairly permeable.

WORKING QUALITIES.—The wood is not very difficult to work when sharp edged tools are used. Sawing difficulties are encountered because of the presence of silica. The wood cuts well with rotary and veneer machines. It has good nail-holding properties and can be easily glued. Planing is comparatively easy and when the wood is brought to a good surface it takes a high polish.

USES.—With an average exploitable girth of 8–10 feet, the wood is used for flooring, interior joinery, and furniture. Quarter-sawn material presents a decorative surface which, when suitably stained, can serve as a substitute for mahogany.

XYLEM ANATOMY.—Growth rings absent. Wood diffuse-porous; vessels mostly solitary or in radial multiples of 2 or 3 pores; elliptical to circular in outline; average pore diameter 210μm, range 98μm–280μm; average vessel element length 420μm, range 224μm–630μm; vessel wall thickness 2μm–4μm; perforation plates exclusively simple; vessel element end wall inclination slightly oblique to transverse; intervascular pitting alternate, apertures somewhat elliptical or slit-like. Imperforate tracheary elements: septate libriform fibers, average length 1540μm, range 1313μm–1875μm. Vascular rays: heterogeneous, mainly multiseriate, generally 3 cells wide, 9 to 20 cells high, few biseriate. Axial parenchyma: paratracheal, sparse, usually 1 or 2 cells ensheathing vessels. Tanniniferous substances: observed in ray cells as well as parenchyma cells.

CRYSTALS.—Cuboidal, many, present in ray cells as well as fibers.

Canarium schweinfurthii (commonly known as the bush candle, African olive, African elemi, or canarium), is a species of large tree native to tropical Africa. Names in many African languages are variations of mupafu.