Koompassia excelsa (Family: Leguminosae)
Medium Hardwood, Vernacular names applied include kayu raja (Sarawak), mengaris (Sabah) and tapang (Sarawak). This is a monospecific timber.
- Density: 800-865 kg/m3
- Heartwood: reddish brown to deep brick-red-brown when fresh and darkens with age to a deep chocolate-brown
- Sapwood: buff-coloured or yellow-brown, often with a pink tinge
- moderately durable under exposed conditions
- texture is rather coarse but even except in areas where included phloem occurs. Grain is interlocked, often deeply interlocked
- nailing property is rated as good
- the major defect that is associated with the timber of tualang is the presence of hard abnormal tissues commonly known as included phloem.
When treated, the timber is suitable for all heavy construction, like posts, beams, joists, columns (heavy duty), piling, railway sleepers and power transmission poles. Untreated, the timber is suitable for flooring (heavy traffic), panelling, mouldings, heavy duty furniture, fender supports, office and shop fittings, tool handles (impact) and plywood.