PERAH
INTRODUCTION
The Standard Malaysian Name for the timber of Elateriospermum tapos (Euphorbiaceae). The ASEAN Standard Name, which is of Indonesian origin, is TAPUS. Vernacular names applied include dungku (Sarawak), kelampai (Sarawak) and perah ikan (Peninsular Malaysia and Sabah). Only one species is recorded, viz. E. tapos. The sapwood is light yellow-brown and is sharply defined from the heartwood, which is dark brown with a red tinge and streaked alternately with lighter and darker stripes. A central core of darker coloured wood may be found in some trees.
Also known as Guhum, Kelampai, Lapak gari, Luba gunung, Pala, Para, Satan and Tapus (Indonesia); and Pee-ra and Pra (Thailand).
DENSITY
The timber is very hard and very heavy with a density of 735-1,235 kg/m3 air dry. The timber is classified under Medium Hardwood in Malaysia.
NATURAL DURABILITY
The timber is non-durable and is susceptible to termite and powder-post beetle attacks.
PRESERVATIVE TREATMENT
Except for the corewood, the timber is easily treated with preservatives.
TEXTURE
Texture is moderately fine and even with straight or shallowly interlocked grain.
STRENGTH PROPERTIES
The timber falls into Strength Group B (Burgess, 1958) or SG3 (MS 544:Part 2:2001).
MACHINING PROPERTIES
It is difficult to saw but planes well and produces a smooth finish.
AIR DRYING
The timber seasons fairly fast with no defects except for some sapstain and insect attacks. 13 mm thick boards take 2.5 months to air dry, while 38 mm thick boards take 4 months.
SHRINKAGE
Shrinkage is high, with radial shrinkage averaging 2.4% and tangential shrinkage averaging 3.3%.
USES
The timber is suitable for medium and heavy construction indoors and when treated, should be suitable for all heavy construction, railway sleepers, flooring, tool handles (impact), columns (light duty), fence posts, telegraphic and power line posts and cross arms.
REFERENCES
- Burgess, H. J. 1958. Strength Grouping of Malaysian Timbers. Malayan Forest Service Trade Leaflet No.25. The Malaysian Timber Industry Board and Forest Research Institute Malaysia, Kuala Lumpur. 15 pp.
- Menon, P. K .B. 1986. Uses of Some Malaysian Timbers. Revised by Lim, S. C. Timber Trade Leaflet No. 31. The Malaysian Timber Industry Board and Forest Research Insitute Malaysia, Kuala Lumpur. 48 pp.
- MS 544: Part 2: 2001: Code Of Practice For Structural Use Of Timber. Permissible Stress Design of Solid Timber.
- , T. M. 1982. A Dictionary of Malaysian Timbers. Revised by Lim, S. C. & Chung, R. C. K. Malayan Forest Records No. 30. Forest Research Institute Malaysia, Kuala Lumpur. 201 pp.