Raspberry jam is generally a small tree 10 m tall with bole length of 2.0 to 2.5 m, but commonly a bushy shrub 3 to 5 m tall with short main stem and numerous spreading branches. It occurs from Kalbarri to the South Coast, and common in the Wheatbelt area on gently undulating topography. However, most vegetation in that area has been cleared for agriculture. The best development is in low woodland and tall shrubland, associated with York gum and salmon gum, with mallee species, or with wandoo in south-westerly areas of the Wheatbelt. Associated shrubs include Acacia microbotrya.
Heartwood is dark-reddish brown and very hard. The grain is attractive, with fiddleback a common feature. Freshly-cut timber has a sweet smell similar to raspberry jam , hence the common name.
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 1260 kg/m3, air-dry density about 1040 kg/m3, and basic density about 940 kg/m3.
Tangential and radial shrinkage before reconditioning are 1.8 and 1.2 per cent respectively. One sample assessed by CALM was 1.4 per cent and 1.0 per cent respectively.
Workability is good, with the timber being relatively easy to work.
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 combined 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 (SD2). The brackets indicate conservative provisional ratings based on the air-dry density.
|Modulus of Rupture||MPa||86||130|
|Modulus of Elasticity||MPa||14200||18500|
|Max Crushing Strength||MPa||43||70|
Limited availability because of clearing restrictions in the Wheatbelt region.
The trunks make excellent fence posts, and sawn timber strainers and rails. The wood has been used for ornamental articles, machine bearings and sheave blocks. It is being assessed for the manufacture of stringed instruments.