Coronavirus (COVID-19) update: We are currently updating information following recent Queensland and Australian Government announcements. Find assistance and support for coronavirus affected businesses and industries.

Silvertop ash

Scientific name

Eucalyptus sieberi syn. E. sieberana. Family: Myrtaceae

Other names

Silvertop; coast ash; ironbark (Tasmania)

Description

  • Tall tree growing to 45m high.
  • Bark covering the trunk is hard and deeply furrowed, contrasting with smooth-barked branches.
  • Bark is dark grey to black.

Occurrence

  • Occurs in the tablelands, central coastal and south coastal New South Wales.
  • Occurs in eastern Victoria and the coastal Gippsland districts.
  • Occurs in the north-eastern corner of Tasmania.

Appearance

Colour

  • Heartwood is pale brown, sometimes with a pink tinge.
  • Sapwood is narrow and indistinguishable.
  • Pinhole borer commonly discolours.

Grain

  • Grain is often interlocked.
  • Texture is medium

Uses

  • Construction: general construction, flooring, panelling.
  • Decorative: steam bending, outdoor furniture.
  • Others: woodchip for paper production, shingles.

Properties

  • Density: 820kg/m3 per at 12% moisture content; about 1.2m3 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 for structural purposes.
  • Joint groups: J2 unseasoned, JD2 seasoned.
  • Shrinkage to 12% MC: about 10% (tangential), 6% (radial).
  • Unit shrinkage: not available.
  • Durability above-ground: Class 2 (life expectancy 15–40 years).
  • Durability in-ground: Class 3 (life expectancy 5–15 years).
  • Lyctine susceptibility: untreated sapwood is not susceptible to lyctid borer attack.
  • Termite resistance: not resistant.
  • Preservation: sapwood will impregnate with preservative.
  • Seasoning: more difficult to season without degrade than the Tasmanian oaks, and dries slower; collapse is significant and reconditioning is desirable.
  • 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: satisfactorily bonds using standard procedures.
  • Finishing: readily accepts paint, stain and polish.

Identification features

General characteristics

  • Sapwood: light brown, and not distinct from the heartwood.
  • Heartwood: pale brown with occasional gum veins and/or flecks, sometimes with pink tints.
  • Texture: moderately open, growth rings may be visible, grain may be interlocked.

Wood structure

  • Vessels: medium to small, solitary, tyloses, obvious vessel lines.
  • Parenchyma (soft tissue): not visible with hand lens.
  • Rays: fine, visible as a darker fleck on radial surfaces.

Other features

  • Burning splinter test: match-size splinter burns to charcoal with no 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, Bathust, 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, Australian Standard International, Strathfield, NSW.