Commercial timbers

H. G. Richter and M. J. Dallwitz


Albizia procera Benth. (White siris, kokko)

Nomenclature etc. MIMOSACEAE. Status of protection under CITES regulations: not protected.

Description based on: 8 specimens. Tree. Geographic distribution: India, Pakistan, Sri Lanka, Burma, Thailand, Laos, Vietnam, Cambodia, and Indomalesia.

General. Growth ring boundaries distinct. Heartwood basically brown, with streaks. Sapwood colour distinct from heartwood colour. Odour indistinct or absent. Grain generally interlocked; heartwood colour from light to dark brown.

Vessels. Vessels present. Wood diffuse-porous. Vessels arranged in no specific pattern, in multiples, commonly short (2–3 vessels) radial rows. Vessel outline rounded. Two distinct vessel diameter classes absent. Average tangential vessel diameter 200–350 µm. Average tangential diameter of vessel lumina very large. Average number of vessels/mm² 1–3. Vessels per square millimetre very few. Perforation plates simple. Intervessel pits alternate, average diameter (vertical) 7–10 µm, medium, vestured. Vessel-ray pits with distinct borders, similar to intervessel pits, of uniform size or type, of the same type in adjacent elements, located throughout the ray. Helical thickenings absent. Tyloses in vessels absent. Other deposits in heartwood vessels present, brown, red, yellow.

Tracheids and fibres. Vascular or vasicentric tracheids sporadic to absent. Fibres very thin-walled and of medium wall thickness. Fibre pits mainly restricted to radial walls, simple to minutely bordered. Helical thickenings absent. Fibres exclusively septate. Septate fibres evenly distributed. Periodic change between thin and thick-walled fibres observed.

Axial parenchyma. Axial parenchyma present, banded and not banded. Axial parenchyma bands marginal (or seemingly marginal), fine, up to three cells wide. Parenchyma bands only sporadically along growth ring limits. Axial parenchyma paratracheal. Paratracheal axial parenchyma vasicentric, aliform, and confluent. Aliform parenchyma lozenge. Axial parenchyma as strands. Average number of cells per axial parenchyma strand 2–5. Unlignified parenchyma absent.

Rays. Rays present, 4–6–8 per tangential mm, multiseriate, also if only few, (1–)2–3(–4) cells wide, 2–3 cells wide. Rays with multiseriate portions as wide as uniseriate portions absent. Aggregate rays absent. Rays of one size. Height of large rays up to 500 µm. Rays composed of a single cell type. Homocellular ray cells procumbent. Sheath cells absent. Tile cells absent. Perforated ray cells absent. 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.

Mineral inclusions. Crystals present, prismatic, located in axial parenchyma cells. Crystal-containing axial parenchyma cells chambered. Number of crystals per cell or chamber one. Crystal containing cells of normal size. Cystoliths absent. Silica not observed.

Physical and chemical tests. Heartwood fluorescent. Water extract not fluorescent. Water extract basically colourless to brown or shade of brown. Heartwood extractives leaching out when in contact with water. Ethanol extract fluorescent. Ethanol extract basically colourless to brown or shade of brown. Chrome azurol-S test negative. Froth test positive. Splinter burns to charcoal.


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