Category :    Heavy Hardwoods

Species

Shorea atrinervosa (balau hitam), S. astylosa (balau gunung), S.exelliptica (balau tembaga), S.falcifera (balau kuning), S.foxworthii (balau bukit), S.glauca (balau laut), S.laevis (balau kumus), S.lumutensis (balau puteh), S.materialis (balau pasir), S.maxwelliana (balau kumus hitam), S.scrobiculata (balau sengkawang darat), S.submontana (balau gajah), S.sumatrana (balau sengkawang air)

General Characteristics

Sapwood well defined; colour of heartwood yellow-brown, brown or reddish-brown; planed surface with medium lustre; with subtle stripe figure; texture moderately fine and even; grain interlocked; hard or very hard and horny to cut across grain; end cut shiny (with metallic lustre); air dry density over 800 kg/m³ (50 lb/ft³) to less than 1155 kg/m³(72 lb/ft³); very durable in the case of balau kumus hitam even under adverse conditions, others are classified as durable.

Structure

Growth rings absent.
Vessels with simple perforation; medium-sized; moderately few; mostly solitary with few radial or oblique groups of 2 to 3; fairly evenly distributed but with a tendency to form short, oblique lines; mostly filled with tyloses but without vessel deposits.
Wood parenchyma of both apotracheal and paratracheal types present. The apotracheal type consisting mainly of irregularly spaced concentric bands with occasional short tangential lines of diffuse strands. The paratracheal type often as incomplete vasicentric, barely visible with a hand lens, but more commonly as scant or fairly well defined aliform.
Rays fine, just visible to the naked eye on cross-section: not prominent on a radial surface.
Ripple marks absent but a slight seggestion of storeying of elements may be occasionally present.
Intercellular canals Vertical canals smaller in size than t

Other Features

Burning splinter test: Splinter burns to ash except S. laevis (balau kumus) which burns to charcoal.
Froth test: Negative.

Uses