Blackbutt

• Moderate to large tree.
• Grows 40–60m high with 1–2m stem diameter.
• Straight slender trunk with circular cross-section.
• Bark on the lower part of the trunk is dark grey-brown, fibrous and fissured.
• Typical smooth gum-type bark on branches and uppermost part of the trunk

• Found in coastal regions from southern New South Wales to Maryborough, Queensland.

Colour

• Heartwood is pale brown with a faint tinge of pink when freshly cut.
• Sapwood is usually slightly paler than heartwood, but sometimes indistinguishable from heartwood.

Grain

• Uniform, moderately-coarse texture.

Engineering

• Sawn or round timber in wharf and bridge construction.
• Railway sleepers.
• Cross-arms, poles, piles, mining timbers.
• Not recommended for in-ground poles when constructing pole-frame houses.

Construction

• Unseasoned, sawn timber in general house framing, fascia and barge boards.
• Seasoned, dressed cladding, internal and external flooring, lining and joinery.
• Fencing, landscaping and retaining walls.

Decorative

• Quality furniture, outdoor furniture.
• Turnery, parquetry.

Others

• Boat building (keel and framing components, planking, decking).
• Coach, vehicle and carriage building.
• Agricultural machinery.
• Structural plywood, hardboard.

• Air dry density: 930kg/m³ at 12% moisture content; about 1.1m³ of seasoned sawn timber per tonne.
• Plantation-grown timber: age 4 years—64% mature timber density; age 11–17 years—80 to 88% mature timber density.
• Strength groups: S2 unseasoned, SD2 seasoned.
• Stress grades: F11, F14, F17, F22 (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: J2 unseasoned; JD2 seasoned.
• Shrinkage to 12% MC: 7.3% (tangential), 4.3% (radial).
• Unit shrinkage: 0.37 % (tangential) 0.26 % (radial)—these values apply to timber reconditioned after seasoning.
• Durability above-ground: Class 1 (life expectancy more than 40 years).
• Durability in-ground: Class 2 (life expectancy 15–25 years).
• Lyctine susceptibility: sapwood is not susceptible to lyctine borer attack.
• Termite resistance: resistant.
• Preservation: sapwood readily impregnates with preservative but penetration of heartwood is negligible using available commercial processes.
• Seasoning: satisfactorily dries using conventional air and kiln seasoning methods; slight tendency to collapse in young wood (near pith).
• Hardness: hard (rated 2 on a 6-class scale) to indent and work with hand tools.
• Machining: machines well.
• Fixing: no difficulty using standard fittings and fastenings.
• Gluing: as with most high-density species, machine and prepare surface immediately before gluing.
• Finishing: readily accepts paint, stain and polish—if these contain high tannin and extractives, then painted surfaces exposed to the weather may stain.

General characteristics

• Sapwood: slightly paler than heartwood.
• Heartwood: light brown with occasional pink colouring.
• Texture: open and uniform; grain straight but occasionally slightly interlocked; sometimes appears and feels greasy, similar to but not as obvious as tallowwood (E. microcorys).

Wood structure

• Growth rings: absent.
• Vessels: medium to large, often arranged in oblique chains; vessel lines are prominent on dressed longitudinal surfaces; frequent tyloses.
• Parenchyma (soft tissue): invisible without a lens.
• Rays: fine.

Other features

• Burning splinter test: match-size splinter burns to charcoal without ash.
• Gum veins: may contain gum (kino) veins.

• Boland, DJ, Brooker, MIH, Chippendale, GM, Hall, N, Hyland, BPM, Johnston, RD, Kleinig, DA and Turner, JD 2006, Forest trees of Australia, 5th edn, 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.