Turpentine

Scientific name

Syncarpia glomulifera. Family: Myrtaceae

Other names

Luster; red luster

Description

  • Large tree grows 40–45m high and 1.0–1.3m in stem diameter.
  • Trunk is straight with good form and little taper.
  • Foliage forms a compact, narrow, shady crown.
  • Underside of leaves are coated with a silver-grey down.
  • Bark is persistent (doesn't shed) over the trunk and branches
  • Bark is thick, fibrous and stringy with deep longitudinal furrows.
  • Bark is brown or reddish brown.
  • Species name is derived from the small amount of oleoresin in the inner bark.

Occurrence

  • Occurs along the eastern coast of Australia from Bateman's Bay, New South Wales, to Cooktown, North Queensland.
  • Best development in the tropics is on elevated sites.
  • Sawn timber is fairly readily available.

Appearance

Colour

  • Heartwood is deep red to red-brown.
  • Sapwood is paler.

Grain

  • Texture is fine to medium but often wavy.
  • Grain is often interlocked.
  • Free from gum veins.

Uses

Engineering

  • Sawn and round timber used to construct wharves and bridges, railway sleepers, mining timbers, marine piling.
  • Main Australian species for marine piling because its high silica content makes it resistant to Teredinidae marine borers.

Construction

  • Seasoned sawn timber in general house framing, internal and external flooring, lining and cladding.

Decorative

  • Plywood, laminated beams and bench tops, joinery and parquetry flooring.

Others

  • Boat building (knees, gunwales, planking, decking).
  • Previous use in oyster stakes, wine casks, mallets, and bearings.

Properties

  • Density: 945kg/m3 at 12% moisture content; about 1.0m3 of seasoned sawn timber per tonne.
  • Strength groups: S3 unseasoned, SD3 seasoned.
  • Stress grades: F8, F11, F14, F17 (unseasoned); F14, F17, F22, F27 (seasoned) when visually stress-graded according to AS 2082—2000: Timber—Hardwood—Visually stress-graded hardwood for structural purposes.
  • Joint groups: J2 unseasoned, JD1 seasoned.
  • Shrinkage to 12% MC: 13.0% (tangential), 6.5% (radial).
  • Unit shrinkage: 0.35% (tangential), 0.23% (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 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: be careful when seasoning because this timber tends to collapse and distort.
  • Hardness: very hard (rated 1 on a 6-class scale) to indent and work with hand tools.
  • Machining: can be abrasive to machine cutters and tools due to silica in the wood.
  • 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.

Identification features

General characteristics

  • Sapwood: cream, distinct from heartwood.
  • Heartwood: deep red to red-brown.
  • Texture: fine to medium, uniform; grain often interlocked.

Wood structure

  • Vessels: small, solitary, numerous and uniformly distributed; may have an occasional narrow zone free from vessels; common tyloses.
  • Vessel lines: fine, but distinct.
  • Parenchyma (soft tissue): indistinct under a lens.
  • Rays: fine but visible with a lens.

Other features

  • Burning splinter test: match-size splinter burns to charcoal—can use this test to distinguish from brush box (with very similar anatomy and appearance) which burns with a sooty flame to a white ash.

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.