Commercial timbers

H. G. Richter and M. J. Dallwitz


Gonioma kamassi E. Meyer (Kamassi, Knysna box)

Nomenclature etc. APOCYNACEAE. Syn.: Tabernaemontana kamassi Eckl., Gonioma kamassi var. brachycarpum E. Meyer. Trade and local names: kamassi, kamassiwood, Knysna boxwood, false Cape box (RSA).

Tree, or shrub. Geographic distribution: southern Africa.

General. Growth ring boundaries distinct or indistinct or absent. Heartwood basically yellow, without streaks. Sapwood colour similar to heartwood colour. Odour indistinct or absent. Basic specific gravity 0.7–0.9 g/cm³.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, exclusively solitary. Average tangential vessel diameter 30–55 µm. Average number of vessels/mm² 50–80. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 3–4 µm. Intervascular pits extremely rare, arrangement and diameter estimated from crossfield pits. Vessel-ray pits with distinct borders, similar to intervessel pits. Helical thickenings absent. Tyloses in vessels absent. Other deposits in heartwood vessels present (yellow).

Tracheids and fibres. Fibres of medium wall thickness to very thick-walled. Fibre pits common in both radial and tangential walls, distinctly bordered. Helical thickenings absent. Fibres non-septate.

Axial parenchyma. Axial parenchyma apotracheal, or paratracheal. Apotracheal axial parenchyma diffuse and diffuse-in-aggregates. Paratracheal axial parenchyma scanty. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 2–8. Unlignified parenchyma absent.

Rays. Rays 6–11 per tangential mm, multiseriate, also if only few, (1–)3–5(–6) cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of two distinct sizes. 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, or 2–4. Sheath cells absent. Tile cells absent. Perforated ray cells present. Disjunctive ray parenchyma end walls indistinct or absent.

Storied structures. Storied structure absent.

Secretory structures. Oil and mucilage cells absent. Intercellular canals absent. Laticifers or tanniniferous tubes absent.

Cambial variants. Included phloem absent. Other cambial variants absent.

Mineral inclusions. Crystals not observed. Silica not observed.

Physical and chemical tests. Heartwood fluorescent (green). Water extract fluorescent (bluish-green). Water extract basically yellow or shade of yellow. Ethanol extract fluorescent (bright yellowish-green). Ethanol extract basically yellow or shade of yellow.


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).

Index