INTRODUCTION

The Standard Malaysian Name as well as the ASEAN Standard Name for the timbers of Atuna spp., Kostermanthus spp., Licania spp., Maranthes corymbosa and Parinari spp. (Chrysobalanaceae). Other vernacular names applied to the trees include kemalau (Peninsular Malaysia), kukut (Sarawak), mentelor (Peninsular Malaysia), merbatu laut (Peninsular Malaysia), merbatu pipit (Peninsular Malaysia), nyalin laut (Sarawak), rasak batu (Sabah and Sarawak) and torog (Sabah). Major species include Atuna cordata, A. nannodes, A. racemosa; Kostermanthus heteropetalus; Maranthes corymbosa; Parinari costata, P. elmeri, P. oblongifolia, P. rigida and P. rubiginosa. The sapwood is lighter in colour but not clearly defined from the heartwood, which is red-brown, sometimes with a yellow tinge.

Also known as Sa (Fiji); Kayu batu, Kepala tupai, Kolaka and Merbatu (Indonesia); Phok (Laos); Tauk-kade (Myanmar); Busu plum (Papua New Guinea); Baritadiang and Liusin (Philippines); and Chi khat phen, Chi ot phen, Mak Mu and Maphok (Thailand).

DENSITY

The timber is a Medium Hardwood with a density of 685-1,000 kg/m3 air dry.

NATURAL DURABILITY

The timber is moderately durable under exposed conditions but is amenable to preservative treatment.

TEXTURE

Texture is moderately coarse but even, with straight, spiral or wavy grain.

STRENGTH PROPERTIES

The timber falls into Strength Group B (Burgess, 1958) or SG 2 (MS 544:Part 2:2001).

MACHINING PROPERTIES

It is difficult to very difficult to resaw and cross-cut due to the presence of silica and the twisted grain. The timber is slightly difficult to plane but the surface produced is smooth.

NAILING PROPERTY

The nailing property is rated as very poor.

AIR DRYING

The timber seasons fairly rapidly with slight defects. Slight cupping, bowing, splitting and some moderate amount of end-checking and staining are the main sources of degrade. 13 mm thick boards take 1.5 months to air dry, while 38 mm thick boards take 3.5 months.

SHRINKAGE

Shrinkage is fairly low, with radial shrinkage averaging 1.6% and tangential shrinkage averaging 2.6%.