Blackwood, Black Wattle, Hickory, Sally Wattle, Mudgerabah
Blackwood occurs from northern Queensland to southern Tasmania between latitudes 16-43o S. It is found near sea level to 1500 m. In the tropical part of its distribution it is found only at higher altitudes. (QLD, NSW, ACT, VIC, SA, TAS)Features:
Blackwood has a long life span. It is usually a tree 10-20 m tall and 50 cm diameter but varies from a small shrub to one of the largest acacias in Australia, reaching 40 m in height and 150 cm diameter in the lowlands of north-western Tasmania. Its branchlets are angular with conspicuous ribs and hairy when young. The dull green phyllodes are narrow to ovate and are almost straight, 8-13 cm long and 7-20 mm wide with a rounded tip and 3-5 prominent longitudinal veins. The flowers are white to very pale yellow in large, globular heads. Flowering time is variable throughout the species' extensive range. Pods are flat, thin, 6-10 cm long and 4-6 mm wide, and twisted or coiled when ripe. The seeds have a distinctive red funicle. There are about 64 000 viable seeds per kilogram. Seeds need pre-treatment in very hot water (90o C.) for one minute to promote germination.Ecology/Way of Life:
Its principal occurrence is in cool or warm, humid climatic zones where the summers are mild to warm. It is frost tolerant but may be damaged at temperatures below -7o C. Mean annual rainfall is 750-1500 mm with a winter maximum in the south and a summer maximum in the north. It grows in a range of topography including lowland swampy areas, mountain slopes and even exposed mountain tops. Best growth is on slightly acidic, relatively fertile podzols and alluvia but it tolerates a wide range of soils. It occurs mainly as an understorey species in cool, temperate rainforest and tall, open eucalypt forest. It is also found in teatree swamps in Tasmania.Interaction with Humans/Threats:
Blackwood is regarded as an outstanding cabinet timber in Australia, and most is harvested from natural forests in Tasmania. It has been extensively grown in plantations in India and South Africa and it shows promise in New Zealand. The timber is moderately hard and takes a high polish. It is mainly used for sliced veneer, especially on particle board for cabinet work and has good acoustical qualities suitable for violin backs. The wood is used for fuel in India and Sri Lanka although it has relatively low density and is not of high quality. Blackwood seedlings are very palatable to native animals and domestic livestock, and its foliage is used for cattle fodder in southern India.
It reproduces from both seed and root suckers and has become a weed species in South Africa where it regenerates in gaps in indigenous forests.Other Comments:
Acacia melanoxylon was described in 1813 by Robert Brown, a Scottish botanist who accompanied Matthew Flinders on his voyage of exploration to Australia in 1801. The name is derived from the Greek akakia = a thorny plant, specifically Acacia arabica; and melanos = black, and xylon = wood.Further Reading:
Boland, D.J., Brooker, M.I.H., Chippendale, G.M., Hall, N., Hyland, B.P.M., Kleinig, D.A., Johnston, R.D. and Turner, J.D. 1984. Forest trees of Australia. 4th ed. Nelson and CSIRO, Melbourne. 687p.
Brown, A.G (ed.) 2001. Advancing blackwood silviculture: a Blackwood Industry group (BIG) workshop. Technical Report. Cooperative Research Centre for Sustainable Production Forestry, Hobart.
Doran, J.C. and Turnbull, J.W. (eds.) 1997. Australian trees and shrubs; species for land rehabilitation and farm planting in the tropics. ACIAR Monograph no. 24. Australian Centre for International Agricultural Research, Canberra. 384p.
Floyd, A.G. 1989. Rainforest trees of mainland south-eastern Australia. Inkata Press, Melbourne. 420p.Topics: Timber Fire Plant structure Fodder Invasive species/Weeds Vegetation types Nitrogen-fixation Climatic zones Soils Waterlogging Firewood Germination
Text & map from Australian Trees and Shrubs, courtesy Australian Centre for International Agricultural Research; text edited by J. Turnbull; photo courtesy S. Searle.Sponsored by: