Jarrah - also known as Swan River Mahogany

Eucalyptus Marginata
Green density: 1170kg per m3
Air dry density: 820kg per m3
Basic density: 670kg per m3
Colour: Heartwood is dark red, while regrowth is pinkish-red. Sapwood is pale yellow.
Texture: Coarse but even.
Grain: Slightly interlocked.
Durability Class: 2-3 for decay and also 2-3 (about 15 years) for decay plus termites. Termite resistant.
Hardness: Green 5.7, Dry 8.5

The mighty Jarrah is one of the most commonly known trees which grow in Western Australia. Some of the larger trees have grown up to 50 metres in height with a 3 metre trunk diameter, judged to be 500 years old.

The long, straight, branch free bole, durability in wet and weathered conditions and resistance to termites made it the first choice for construction timbers such as bridges and house frames. Jarrah has a rich, reddish brown colour and is a traditional choice for flooring, paneling and furniture making.


Eucalyptus diversicolor
Green density: 1200kg per m3
Air dry density: 900kg per m3
Basic density: 690kg per m3
Colour: Heartwood is pale pink to reddish brown, regrowth is lighter. Sapwood is a distinguishable white.
Durability Class: 2-3 for decay (about 15 years) and 4 for decay plus termites (less than 8 years); sapwood is susceptable to the borer beetle.
Hardness: Green 6.0, Dry 9.0

Famous for being the tallest tree grown in the south-west of Australia, it also ranks among the tallest in the world. Karris can grow to 90 metres in height and reaches its optimum height within 100 years. Manjimup is home to the “Four Aces”, four magnificent Karri trees perfectly aligned that are between 300 and 400 years old and began life long before Captain Cook first landed on Australian soil.

Its density means it is one of the most reliable timbers for heavy duty purposes, making it our first choice for gluts, bearers, sleepers and crane mats. There has also been a recent shift in its popularity for slabs and other furniture timbers as people are beginning to appreciate its blended appearance of soft pinks and deep burgundies.

Blackbutt (WA variety) - also known as Yarri, WA Blackbutt, Swan River Blackbutt

Eucalyptus patens
Green density: 1120kg per m3
Air dry density: 850kg per m3
Basic density: 690kg per m3
Colour: Heartwood is pale yellow-brown. Sapwood is noticeably paler.
Grain: Interlocked, which can make working with this otherwise easy timber difficult.
Durability Class: 2 for decay (15-25 years), 4 for decay plus termites (less than 8 years).
Hardness: Green 5.5, Dry 6.9

The Blackbutt tree, grows up to 45 metres high, with a bole of half that, and with a trunk diameter up to 2 metres. The tree derives its common name from the fact that it is one of the least flammable of the eucalypts and usually survives moderate forest fires with only an increased blackening of its bark.

The yellow to honey coloured timber has similar characteristics to that of Jarrah and is widely sought after as an alternative to the darker timbers for flooring and paneling.

Marri - also known as Redgum

Corymbia calophylla, formerly Eucalyptus calophylla
Green density: 1200kg per m3
Air dry density: 850kg per m3
Basic density: 650kg per m3
Colour: Heartwood ranges from pale yellow to light brown to reddish brown. Sapwood is distinguishably paler.
Durability Class: 3-4 for both decay and decay plus termites (about 8 years). Sapwood is susceptable to borer beetle.
Hardness: Green 6.6, Dry 7.1

The Marri tree is another variety of the “Tall Timbers” which grow in the south-west of Western Australia. They can reach a height of 60 metres and be between 200 and 300 hundred years old.

The timber varies in colour from pale yellow to warm browns giving flooring a natural appeal. Marri typically holds more gum in its grain than Jarrah, Karri or Blackbutt and is sought after for this unique feature.

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