Other species of Palaquium are sold under the standard trade names nyatoh (with other genera of the Sapotaceae family), nyatoh-batu (harder, heavier species) and red silkwood (P. galactoxylum, once harvested from Queensland forests).
- Tall hardwood to 30m high and 1m diameter.
- Some species are buttressed.
- Outer bark is brown, grey or red depending on species.
- Occurs on varied sites from coastal peat swamps to mountainous regions.
- Widely distributed including:
- Papua New Guinea
- Solomon Islands
- Heartwood is generally pink to red-brown, but varies between species.
- Sapwood is pink-brown and not always distinct.
- Grain is straight to interlocked with a moderately fine texture.
- Construction: light construction, protected framing and boards, internal covered flooring.
- Decorative: interior joinery, mouldings, lining, panelling, veneer, cabinet work.
- Others: dowels, turnery, carving, furniture carcasses, boat building; often seen in Australia in outdoor settings and BBQ trolleys.
- Density: 540–720 kg/m3 at 12% moisture content; about 1.8m3 of seasoned sawn timber per tonne.
- Strength groups: S6 unseasoned, SD7 seasoned.
- Stress grades: F4, F5, F7, F8 (unseasoned); F5, F7, F8, F11 (seasoned) when visually stress-graded according to AS 2082—2000: Timber—Hardwood—Visually stress-graded for structural purposes.
- Joint groups: JD4 seasoned.
- Shrinkage to 12% MC: P. galactoxylum—4.2% (tangential), 1.5% (radial); P. hornei—7.8% (tangential), 6.1% (radial); P. amboinense—3.9% (tangential), 1.7% (radial).
- Unit shrinkage: P. galactoxylum—0.29% (tangential), 0.14% (radial); P. hornei—0.36% (tangential), 0.28% (radial); P. amboinense—0.25% (tangential), 0.14% (radial).
- Durability above-ground: Class 4 (life expectancy less than 7 years).
- Durability in-ground: Class 4 (life expectancy less than 5 years).
- Lyctid susceptibility: untreated sapwood susceptible to lyctid borer attack.
- Termite resistance: not resistant.
- Preservation: sapwood and heartwood cannot be readily impregnated with preservatives using currently available commercial processes.
- Seasoning: be careful when drying to minimise distortion, collapse and checking.
- Hardness: soft (rated 5 on a 6-class scale) to indent and work with hand tools.
- Machining: working properties vary with silica content; generally, easy to work with both machine and hand tools.
- Fixing: no difficulties using standard fittings and fastenings.
- Gluing: satisfactorily bonds using standard procedures.
- Finishing: readily accepts paint, stain, and takes a good polish after filling.
- Sapwood: light pink-brown, only slightly distinct from heartwood.
- Heartwood: reddish brown, pink brown, tends to fade with exposure.
- Texture: fine and even, grain is straight to interlocked or wavy.
- Vessels: medium size, visible to the unaided eye; some solitary, but mostly as radial multiples of 2–6 in chain-like form; tyloses ; obvious vessel lines.
- Parenchyma (soft tissue): apotracheal as regularly spaced, fine bands.
- Rays: very fine, visible through lens only.
- Burning splinter test: match-size splinter burns to an ash.
- Froth test: most species of palaquium test positive.
Research and resources
- Boland, DJ, Brooker, MIH, Chippendale, GM, Hall, N, Hyland, BPM, Johnston, RD, Kleinig, DA and Turner, JD 2006, Forest trees of Australia, 5th ed., CSIRO Publishing, Collingwood Australia.
- Bootle, K 2005, Wood in Australia: Types, properties and uses, 2nd ed., McGraw-Hill, Sydney.
- 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