Wandoo is commonly called 'white gum', and is usually a medium to large tree up to 25 m height and with diameter at breast height (dbh) to 0.8 m, but is occasionally found up to 30 m tall and 1m dbh. Wandoo grows in the 380 to 500 mm rainfall zone of south-west Western Australia, either in broad shallow valleys or on low ridges, with the best wandoo forests occurring between Darkan and Quindanning and up to Toodyay.
Heartwood is yellow to light reddish brown, and the sapwood band is very narrow.
Green density is the density of wood in the living tree, defined as green mass divided by green volume, and useful for estimating transport costs. It varies with season and growing conditions.
Air-dry density is the average mass divided by volume at 12 per cent moisture content (this is the average environmental condition in the coastal capital cities around Australia).
Basic density is oven-dry mass divided by green volume. This measure has the advantage that moisture content variations in the tree during the year are avoided.:
Green density is about 1280 kg/m3, air-dry density about 1100 kg/m3, and basic density about 920 kg/m3.
Tangential and radial shrinkage before reconditioning are 4.0 and 2.5 per cent respectively, and after reconditioning 2.6 and 2.3 per cent respectively.
The timber is difficult to work because of its high density but machines to a smooth surface. The grain is interlocked or wavy and careful drying is required to avoid checks and end splits.
The CSIRO Durability Classes are based on the performance in ground of outer heartwood when exposed to fungal and termite attack.
|1||More than 25|
|2||15 to 25|
|3||8 to 15|
|4||Less than 8|
The ratings are not relevant to above-ground use. In late 1996, CSIRO published revised ratings, which include termite susceptibility. Ratings are now available for about seventy species for decay, and for decay plus termites.:
Durability Class based on the CSIRO 1996 ratings is 1 for decay, and 1 for decay + termites.
Minimum values (MPa) for strength groups for green and seasoned timber come from Australian Standard AS2878-1986 'Timber - Classification of strength groups'. In grading structural timber, each species is allocated a ranking for green timber of S1 (strongest) to S7, and for seasoned timber SD1 (strongest) to SD8.
MOR is modulus of rupture or bending strength, MOE is modulus of elasticity or 'stiffness', and MCS is maximum crushing strength or compression strength. Hardness refers to the Janka hardness test and is a measure of resistance to indentation.
Minimum values (Mpa) for green timber
Minimum values (Mpa) for green timber
Where test data were available, they are shown in bold print. Most values are from Bootle (1983), Wood in Australia. Types, properties and uses. (McGraw-Hill), or Julius (1906), 'Western Australian timber tests 1906: The physical characteristics of the woods of Western Australia'.
Where no strength data were available, air-dry density was used in accordance with the Australian Standard AS2878-1986 Timber - Classification of strength groups to predict the strength group. Consequently, the strength values quoted are from the above two tables.:
Green and dry strength groups are S2 and SD3. The more important strength properties are given in the table below.
|Modulus of Rupture||MPa||100||142|
|Modulus of Elasticity||MPa||14000||17000|
|Max Crushing Strength||MPa||55||82|
Limited quantities of flooring, decking and posts are available in Western Australia.
Uses of wandoo have been mainly for heavy and light construction, poles, sleepers, and flooring. The bark and wood were harvested in the past because they contain commercial quantities of tannins, the extraction of which was once a medium-sized industry in the wandoo area.