The Tree
A large tree, attaining a height of 45m to 60m and a diameter of 2m to 3m.

The Timber
Karri closely resembles jarrah in structure and appearance, the heartwood being reddish-brown darkening to a rather more uniform brown than jarrah. The burning splinter test is generally useful in separating the two timbers. When a small splinter of dry heartwood is burned the embers continue to glow after the flame is extinguished. With karri, a thick white ash is formed, while jarrah burns to a black, ashless charcoal. Karri is slightly heavier than jarrah, and weighs about 900 kg/m3 when dried.

Drying
The timber requires great care in drying; it is prone to checking, and under adverse drying conditions, the cracks can extend well into the wood. Thin stock is more liable to warping than with jarrah. Partial air drying prior to kiln drying produces the best results.

Strength
A hard, strong timber, which compared with European oak is some 40 to 50 per cent stronger in bending, in compression along the grain and in shear, and is about twice as stiff. It is about 30 per cent more difficult to split than oak, and in shock resistance is more comparable to European ash.

Working Qualities
Difficult - Difficult to work with hand tools, and fairly difficult to machine. It has a slightly higher blunting effect on cutting edges than jarrah, and like that timber finishes better when the cutting angle is reduced to about 1 50: It can be glued, screwed, stained and polished satisfactorily, but is hard to nail.