Colour. Heartwood yellowish-brown or orange-brown when first cut, turning darker with age to brown or deep reddish brown. Sapwood white, pale yellow or buff and sharply differentiated from heartwood. Grain. Grain variable but usually interlocked or wavy, texture is coarse but even. Attractive figure on backsawn material.
Species Name: Kwila / Merbau
Botanical name(s): Intsia bijuga (formerly Afzelia bijuga syn. Afzelia australis), I. palembanica. Family name: Leguminosae.
Localised names: Johnstone River teak, scrub mahogany (North Queensland), merbau (Malaysia), vesi (Fiji), Moluccan ironwood (United Kingdom), go-nux (Vietnam), ipil (Philippines), hintzy (Madagascar), melila, bendora (Papua New Guinea), lumpho, lum-paw, makamong (Thailand), kivoli, vuvula (Solomon Islands).
Size and location information: A large hardwood attaining 40 m in height, with a trunk of 0.6 m diameter. Often a bushy tree forming a spreading canopy.
Occurs in the Johnstone River and Daintree areas of North Queensland, Malaysia, Fiji, Vietnam, Philippines, Madagascar, Papua New Guinea, Thailand, Solomon Islands, New Caledonia, Vanuatu and Samoa.
Density: 830 kg/m3 at 12% moisture content; approximately 1.2 m3 of seasoned sawn timber per tonne.
Shrinkage: 1.2% Radial, 2.6% tangential
Durability: In ground: Class 3 Above ground: Class 1
Lyctids Susceptibility : Yes.
Termite Resistance (AS3660) : Yes.
Strength Group: S2/SD3
Workability : Machining. Working properties variable. Cuts cleanly but may have a blunting or gumming effect on cutting edges. Cutting angle should be reduced to 20 degrees when planing quarter-sawn stock. Turns well.
Fixing. Kwila tends to split unless pre-bored, but holds fastenings well.
Gluing. Glues satisfactorily except with casein glues.
Finishing. It takes paint, stain and polish well, but gum bleed-through or oily patches may affect the finish.
Uses : Engineering. Cross arms, bridge building, piles, sleepers, posts, wharfing, mining timbers.
Availability : Merbau plentiful. Kwila getting differcult.