Golden-wreath Wattle, Coojong, Orange Wattle, Blue-leafed Wattle, Western Australian Golden Wattle
This acacia is common on poor, sandy soils in south-western Western Australia between latitudes 27-35o S. and altitudes from near sea level to 300 m. (WA)Features:
A small, fast-growing, nitrogen-fixing tree or bushy shrub up to 9 m tall. The young plant has dense, sometimes greyish-blue foliage. Phyllodes are long, 8-25 cm, and narrow, 4-20 mm, green or greyish, tapering gradually towards the base and apex, and with a conspicuous midrib. Flower heads are globular and a deep yellow-orange. Pods are 5-14 cm long and 5-6 mm wide, straight or slightly curved, and slightly indented between the seeds. It flowers August - October and the seed is ripe November - January. There are about 46 000 viable seeds per kilogram and the seed should be immersed in boiling water for one minute to promote germination.Ecology/Way of Life:
The main occurrence is in warm, sub-humid and humid climatic zones but it does extend into the semi-arid zone. Most of the area is frost-free but inland a few frosts occur each year. Mean annual rainfall is 500-1000 mm except in the semi-arid zone where it can be as low as 300 mm. This acacia grows mainly on gentle undulating topography and coastal sand plains. It occurs on many soil types, especially poor and calcareous sands but also on clays and a range of podzolic soils. It often occurs in eucalypt woodland dominated by E. gomphocephala, E. loxophleba and E. wandoo, and in semi-arid areas in low woodlands and mallee communities.Interaction with Humans/Threats:
Its fast growth, ability to coppice and tolerance of a wide range of soils has resulted in it being extensively planted in North Africa, the Middle East and South America for animal fodder, fuelwood, sand stabilisation and as a windbreak. Over 200 000 ha have been planted in North Africa as a supplementary fodder source for sheep and goats. In Australia it is commonly used as an ornamental but is being planted on farms for fodder and to mitigate salinity by lowering water tables. In earlier times it was planted for tannin production as the bark contains about 30% tannin. This acacia has become a major weed in South Africa invading and displacing native vegetation. It has also spread in parts of southern and eastern Australia.Other Comments:
Acacia saligna (named by Heinrich Wendland in 1820, based on the Greek akakia = a thorny plant, specifically Acacia arabica; and the Latin salignus = willowy or willow-like, referring to its drooping branches. Formerly it was known as Acacia cyanophylla).Further Reading:
Crompton, H. 1992. Acacia saligna - for dryland fodder and soil stabilization. NFT Highlights 92.03. Nitrogen Fixing Tree Association, Hawaii.
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.
Hall, N. et al. 1972. The use of trees and shrubs in the dry country of Australia. Australian Government Publishing Service, Canberra. 558p.
Maslin, B.R. 1974. Studies in the genus Acacia. 3: The taxonomy of A. saligna (Labill.) H. Wendl. Nuytsia 1: 332-340.Topics: Soils Windbreak Firewood Ornamental Fodder Soil Conservation Plant structure Climatic zones Vegetation types Agroforestry Salinity issues Salt-tolerance Germination Invasive species/Weeds Nitrogen-fixation
Text & map from Australian Trees and Shrubs, courtesy Australian Centre for International Agricultural Research; text edited by J. Turnbull; photo courtesy B. Maslin.Sponsored by: