WA blackbutt has the common name ‘yarri’. WA blackbutt is usually a tall tree up to 45 m in height, with diameter at breast height to 1.8 m and a relatively large straight bole. On less favourable, particularly swampy sites, it is a smaller tree of poor form. It has a natural distribution that coincides closely with that of jarrah (E. marginata), from near Perth in the north to Albany on the south coast.
Wood description [more info]
Heartwood is pale yellowish-brown, and the sapwood is sufficiently paler to be distinguishable.
Wood density [more info]
Green density is about 1120 kg/m3, air-dry density about 850 kg/m3, and basic density about 690 kg/m3.
Shrinkage [more info]
Tangential and radial shrinkage before reconditioning are 10.0 and 5.0 per cent respectively, and after reconditioning 7.0 and 3.5 per cent respectively.
Workability [more info]
The timber is relatively easy to work, although interlocked grain can make it difficult.
Durability [more info]
Durability Class based on the CSIRO 1996 ratings is 2 for decay, and 4 for decay + termites. Sapwood is Lyctus-susceptible.
Strength group and properties [more info]
Green and dry strength groups are S4 and SD5. The more important strength properties are given in the table below.
|Modulus of Rupture||MPa||66||99|
|Modulus of Elasticity||MPa||12000||13000|
|Max Crushing Strength||MPa||37||65|
Uses [more info]
Blackbutt’s main use has been in flooring, although in the past it was used for general construction, case manufacture, sleepers, flooring and panelling.
Availability [more info]
Availability is limited, because a large part of the resource is now conserved in stream reserves. The timber is available in small quantities in Western Australia.
Source : Forest Products Commission WA