- A lesser species, A. crassicarpa, is also known as brown salwood.
Acacia aulacocarpa, A. mangium, A. crassicarpa. Family: Leguminosae
black wattle; hickory wattle (both species); sally wattle (A. mangium)
- Medium-size hardwood with flanged buttresses.
- Grows to 30m high and 1m diameter on favourable sites.
- Bark is thin, brown, hard and fissured.
- Northern New South Wales along the eastern coast of Queensland to Cape York.
- Coastal areas of the Northern Territory.
- Heartwood varies from light brown to brown, often streaked with darker markings.
- Sapwood creamy white to pale brown.
- Variable grain, coarse texture but rather even.
- Limited use, in the past, for general house framing, flooring, linings and mouldings, but rarely used now for these purposes.
- Shop and office fixtures.
- Walking sticks.
- Fishing rods.
- Archery bows.
- Tool handles (axes and hammers).
- Boat building (light).
- Density at 12% moisture content; and about 1.3m3 of seasoned sawn timber per tonne:
- aulacocarpa 800kg/m3
- mangium 690kg/m3
- crassicarpa 675kg/m3.
- Strength groups:
- A. aulacocarpa (S4) unseasoned; (SD4) seasoned
- A. mangium (S5) unseasoned; (SD5) seasoned
- A. crassicarpa (S5) unseasoned; (SD5) seasoned.
- Stress grades: visually stress-graded according to AS 2082—2000: Timber—Harwood—Visually stress-graded hardwood for structural purposes
- aulacocarpa F7, F8, F11, F14 (unseasoned), F11, F14, F17, F22 (seasoned)
- mangium F5, F7, F8, F11 (unseasoned), F8, F11, F14, F17 (seasoned)
- crassicarpa F5, F7, F8, F11 (unseasoned), F8, F11, F14, F17 (seasoned).
- Joint groups:
- A. aulacocarpa JD2 seasoned
- A. mangium JD3 seasoned
- A. crassicarpa J2 unseasoned; JD3 seasoned.
- Shrinkage to 12% MC: 4.2% (tangential), 1.4% (radial)—these values apply to A. aulacocarpa.
- Unit shrinkage: 0.36% (tangential), 0.14% (radial)—these figures apply to timber of A. aulacocarpa reconditioned after seasoning.
- Durability above-ground:
- A. aulacocarpa Class 2 (life expectancy 15–40 years)
- A. mangium Class 3 (life expectancy 7–15 years)
- A. crassicarpa Class 3 (life expectancy 7–15 years).
- Durability in-ground:
- A. aulacocarpa Class 2 (life expectancy 15–25 years)
- A. mangium Class 3 (life expectancy 5–15 years)
- A. crassicarpa Class 3 (life expectancy 5–15 years).
- Lyctine susceptibility: untreated sapwood susceptible to lyctine borer attack.
- Termite resistance: not resistant.
- Preservation: sapwood will impregnate with preservative.
- Seasoning: satisfactorily dries using conventional air and kiln seasoning.
- Hardness: moderately hard (rated 3 on a 6-class scale) to indent and working with hand tools.
- Machining: relatively easy to work and machine; turns well to a smooth finish.
- Fixing: no difficulties using standard fittings and fastenings.
- Gluing: satisfactorily bonds using standard procedures.
- Finishing: staining is normally not necessary—it polishes and paints well.
- Sapwood: creamy white, distinct from heartwood.
- Heartwood: light brown to chestnut, occasionally with darker streaks.
- Texture: medium to coarse; straight grain; lustrous.
- Vessels: medium to large, visible without lens, solitary and radial chains of up to 3, uniform distribution; vessel size tends to decrease with the zone of latewood; vessel lines visible.
- Parenchyma (soft tissue): indistinct.
- Rays: very fine, barely visible with lens.
- Burning splinter test: match-size splinter burns to charcoal.
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