Narrow-leaved red ironbark

Scientific name

Eucalyptus crebra. Family: Myrtaceae

Local names

Ironbark, narrow-leaved ironbark, red ironbark

Description and natural occurrence

A large hardwood with deeply furrowed, grey or black bark. Grows to 30 m in height and 0.7 m in diameter. It is the most widely distributed of the ironbarks occuring across the Great Dividing Range and inland. Extends from Sydney to Cairns, growing on a wide variety of soils and is drought and frost resistant.

Wood appearance

Colour. Heartwood is red-brown to dark red and sapwood white to pink-white.

Grain. Close-grained, occasionally interlocked.

Wood properties

Density. 1090 kg/m3 at 12% moisture content; approximately 0.9 m3 of seasoned sawn timber per tonne.

Strength groups. S2 unseasoned; SD3 seasoned.

Stress grades. F11, F14, F17, F22, (unseasoned), F14, F17, F22, F27, (seasoned), when visually stress graded in accordance with AS 2082-1979, Visually stress-graded hardwood for structural purposes.

Joint groups. J1 unseasoned; JD1 seasoned.

Shrinkage to 12% MC. Approximately 5% (tangential); 3.5% (radial).

Unit shrinkage. Not available.

Durability above-ground. Class 1 - life expectancy over 40 years.

Durability in-ground. Class 1 - life expectancy over 25 years.

Lyctine susceptibility. Sapwood is not susceptible to lyctid borer attack.

Termite resistance. Resistant.

Preservation. Sapwood readily accepts preservative impregnation.

Seasoning. Slow to dry, has greater resistance to surface checking than the other commercial ironbarks.

Hardness. Very hard (rated 1 on a 6 class scale) in relation to indentation and ease of working with hand tools.

Machining. Hard to work due to density and interlocking grain.

Fixing. No difficulties have been experienced with the use of standard fittings and fastenings.

Gluing. As with most high-density species, machining and surface preparation should be done immediately before gluing.

Finishing. Will readily accept paint, stain and polish.

Uses

Engineering. Sleepers, girders, bridgework, wharves, heavy engineering construction, poles.

Construction. As unseasoned timber in general house framing and as seasoned dressed timber in cladding, internal and external flooring, linings and joinery. Also in fencing, landscaping and retaining walls.

Decorative. Despite their hardness, the ironbarks have found favour with woodcraftsmen who have salvaged old yards, fence posts, etc for furniture and turnery.

Others. Outdoor furniture.

Identification features

General characteristics

Sapwood. White to pink-white, distinct from heartwood.

Heartwood. Red brown to dark red.

Texture. Fine texture, grain shallowly interlocked.

Wood structure

Vessels. Small, solitary and numerous. Vessel lines inconspicuous. Vessels tylosed.

Further reading

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 edn, McGraw-Hill, Sydney.

Hopewell, G (ed.) 2006, 'Construction timbers in Queensland: properties and specifications for satisfactory performance of construction timbers in Queensland, Class 1 and Class 10 buildings', books 1 and 2, Department of Primary Industries and Fisheries, Brisbane.

Ilic, J 1991, 'CSIRO atlas of hardwoods', Crawford House Press, Bathurst, Australia.

Standards Australia, 2000, 'AS 2082-2000: Timber - hardwood - visually stress-graded for structural purposes', Standards Australia.

Last updated 16 August 2010