Timber selection considerations

Specific uses for special timbers

Because of their particular qualities, some timbers have special applications.

Cypress pine contains a resinous substance that makes it termite-resistant, and guagol and callitral, which make it resistant to decay. Hence, it has a special value as scantling, flooring, weatherboards and lining for house construction, as well as fence posts and trellis supports in vineyards.

Lignum vitae, while not a structural or cabinet timber, possesses a density and hardness that makes it particularly suitable for bearings for artillery weapons, stern tube bearings in ships, pulley sheaves, gear wheels, mallet heads and parts for tools. There is a marked difference in colour between the heartwood, which is dark brown, and the sapwood, which is yellow.

Teak, seen in furniture and veneer, has long been used for joinery and decking on ships and boats. The properties that make it appropriate for such work are long-wearing qualities with little shrinkage, twisting or warping, and, being an oily species, an ability to withstand the effects of water. It is also highly resistant to fire and termites.

Spotted gum, a useful structural timber, also has high shock-resistance and good bending qualities, making it ideal for ships' ribs and planks, and for vehicle bodybuilding, and bent work: It is the best available Australian timber for tool handles.

Turpentine, a structural timber, is particularly resistant to the marine borer, Teredo, and is used for building wharves. For wharf piles the bark is left on, since it is generally believed that the wood's Teredo-repellent qualities are due mainly to an oleoresin produced by the inner bark. Turpentine is the least inflammable of all Australian timbers.

Meranti, Phillippine mahogany and luaun (all from the Shorea family). The cheapest and most readily available of the hardwoods (as of 2017). Works well, apart from the lighter coloured varieties which tend to collapse when chiselling across the grain. There is a tendency for these timbers to split along the grain and care should be taken. Relatively straight grained and knot free, these timbers can take a good finish but some examples have a furry surface and need the grain to be lifted and re-sanded.

The following tables give information on hardwoods and softwoods, Australian and imported. Note, some are getting quite scarce and are now protected.

Sustainable wood production in Australia's forests

(as reported in Australia's State of the Forests Report 2013)

• The area of multiple-use public native forest harvested annually for wood declined from about 117,000 hectares in 2006–07 to about 79,000 hectares in 2010–11, a decrease of 32%.

• Average sustainable sawlog harvest yields from public multiple-use native forests declined by 47% nationally between 1992–96 and 2006–11 (due to increased forest reservation, increased restrictions on harvesting in codes of forest practice, revised estimates of forest growth and yield, and the impacts of broadscale wildfires).

• Actual sawlog harvest from native forest also declined; nationally, the actual sawlog harvest levels were below sustainable yield levels by 17% for the period 2006-11. Pulplog harvests from native forests also declined.

• Over the period 1992–96 to 2006–11, the sawlog and pulplog harvest from softwood plantation forests increased, as did the pulplog harvest from hardwood plantation forests.

• Plantation forests produce 71% of Australia's total log supply: hardwood plantation forests provide 35% of the pulplog supply and 1% of the sawlog supply, while softwood plantation forests provide 39% of the pulplog supply and 79% of the sawlog supply.