Balanocarpus heimii. Family: Dipterocarpaceae
- Straight-boled (trunk), large hardwood.
- Grows to 25m high on good sites.
- Occurs in peninsular Malaysia in a wide range of conditions from low-lying swamp flats to hills at 10,000m.
- Limited occurrence in Thailand.
- Sapwood is pale yellow and well defined.
- Heartwood is yellow to dark brown, often with a green tinge.
- Grain is usually slightly interlocked producing a vague ribbon figure (pattern) on the radial face.
- Even, medium texture.
- Engineering: structural members requiring high strength and durability, railway sleepers, wharf and bridge constructions, poles, piles, mining timbers.
- Construction: heavy duty flooring, decking.
- Others: boat building, truck bodies, casks, vats, churns.
- Density: 930kg/m3 at 12% moisture content; about 1.0m3 of seasoned sawn timber per tonne.
- Strength groups: S1 unseasoned, SD2 seasoned.
- Stress grades: F14, F17, F22, F27 (unseasoned); F17, F22, F27, F34 (seasoned) when visually stress-graded according to AS 2082—2000: Timber—Hardwood—Visually stress-graded for structural purposes.
- Joint groups: JD2 seasoned.
- Shrinkage to 12% MC: 6.3% (tangential), 1.0% (radial).
- Unit shrinkage: not available.
- Durability above-ground: Class 1 (life expectancy more than 40 years).
- Durability in-ground: Class 1 (life expectancy more than 25 years).
- Lyctine susceptibility: sapwood is not susceptible to lyctine borer attack.
- Termite resistance: resistant.
- Preservation: sapwood moderately resists treatment with preservatives.
- Seasoning: slow seasoning timber with very low shrinkage and dries with minimal degrade.
- Hardness: hard (rated 1 on a 6-class scale) to indent and work with hand tools.
- Machining: works well for a high-density timber except for the presence of resin; a cutting angle of 20° recommended on interlocked, quarter-sawn material to prevent 'picking-up'.
- Fixing: pre-drill before nailing.
- Gluing: due to high density, machine and prepare surface immediately before gluing.
- Finishing: be careful due to the resin; obtains a good finish.
- Sapwood: well defined from heartwood.
- Heartwood: dark tan brown, lustrous planed surface, sometimes with subdued strip figure (pattern).
- Texture: moderately fine and even, interlocked grain, hard to cut across the grain.
- Vessels: medium size, mainly solitary, others in radial pairs or short multiples, evenly distributed; filled with tyloses.
- Parenchyma (soft tissue): numerous, short, fine apotracheal strands and closely spaced tangential lines, often not clearly visible with hand lens.
- Rays: moderately fine, not easily seen on a radial surface.
- Ripple marks: characteristic and very distinct.
- Intercellular canals: vertical canals, smaller than vessels, filled with white resin, concentric and often discontinuous.
- Burning splinter test: match-size splinter burns to ash.
Research and resources
- Ilic, J 1991, CSIRO atlas of hardwoods, Crawford House Press, Bathurst, Australia.
- Queensland Government, DAF 2018, Construction timbers in Queensland: Properties and specifications for satisfactory performance of construction timbers in Queensland. Class 1 and Class 10 buildings, Books 1 & 2, Department of Agriculture and Fisheries, Brisbane.
- Standards Australia, 2000, AS 2082—2000: Timber—Hardwood—Visually stress-graded for structural purposes, Standards Australia International, Strathfield, NSW.
- Last reviewed: 12 Dec 2018
- Last updated: 12 Dec 2018