Silvertop ash

Scientific name

Eucalyptus sieberi syn. E. sieberana. Family: Myrtaceae

Other names

Silvertop; coast ash; ironbark (Tasmania)


  • 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.


  • 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.



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


  • Grain is often interlocked.
  • Texture is medium


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


  • 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.