Tasmanian Blue Gum
A tough but pale hardwood, its notable hardness and density makes it ideal for floors, fittings and surfaces expected to take considerable wear.
Tasmanian blue gum is pale straw to brown, often with blue to green-grey tones. The sapwood is paler than the heartwood, but often difficult to distinguish. Blue gum is one of Tasmania’s most durable timbers, which, combined with its strength, makes it a good structural timber. In keeping with its density, blue gum has to be seasoned and worked with care.
The timber established a reputation with early European settlers for its toughness and durability, particularly for bridge construction and wharf piling. More recently, its potential as an appearance timber has been recognised. The leaves and large flower cases of the tree have a strong and characteristic fragrance. Oils extracted from blue gum leaves were also exported for use in medicines and varnishes.
Blue Gum grows rapidly and is easily raised from seed. While it grows up to a metre per year, intense cultivation can double these rates. Blue Gum does not tolerate frost. Its best natural development is in the moist valleys of hilly areas on good quality loams, and likes dolerite and shallow humus soils over mudstone.
Blue Gum grows naturally along the east coast, usually within 20km of the coast, but in some areas up to 60–70km inland. It is also found in the south and west and on some Bass Strait islands.
Blue Gum occurs in dry and wet eucalypt native forest type and 35% of these forest types are reserved. There are currently approximately 23,800ha of Blue Gum in plantations, which is about 10% of Tasmania’s plantations.
Buds usually grow alone, though they can grow in groups of three, and are large, warty and covered in a fine powder.
The Blue Gum flowers from September to December. Once open, the buds shed a round cap and display characteristic white flowers before developing into ribbed gum nuts about 25mm across.
The Blue Gum’s juvenile leaves are up to 15cm long, have a red edge, and are covered with a blue-grey waxy bloom. The leaves of older trees are dark green, tough, sickle-shaped and roughly 25cm.
The bark at the base of the tree is rough, red-brown and peels off in ribbons. At the top of the trunk and branches, the tree is smooth with a dappled grey and cream bark.