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MISCELLANEOUS PUBLICATION 1271. U.S. DEPARTMENT OF AGRICULTURE 



will not support livestock, so the question of 

 management does not arise. However, in the north 

 some areas of spinifex (mainly Triodia pungens 

 and Pleetrachne spp.) are grazed {2Jf). In the 

 Pilbara area of Western Australia, the original 

 communities were dominated by unpalatable spin- 

 ifex but contained a small proportion of better 

 perennial grasses. Under grazing, the softer grass 

 component was eliminated and replaced by spini- 

 fex. making the country useless for grazing. On 

 the deeper soils, it has been found (33) that palat- 

 able grasses can be maintained by a combination 

 of burning in the summer to kill the spinifex 

 and deferment to allow the softer grasses to de- 

 velop. 



Flood Plains 



Flood plains (fig. 6) or frontage country occur 

 along the larger watercourses, but there are also 

 a very large number of small flood plains asso- 

 ciated with minor channels and scattered through- 

 out other rangeland types. Many of the natu- 

 ral waterholes are in the flood plains and so they 

 were the first areas stocked. Stock tend to con- 



centrate on them and so they have been heavily 

 grazed since settlement. As a result, most are 

 in poor condition and many areas are severely 

 eroded. However, even in their poor condition 

 they produce short, attractive forage following 

 rain or floods, and are preferentially grazed by 

 stock. Where large enough, they should be fenced 

 and managed separately. Where too small to 

 manage separately, the management of the com- 

 plex in which they occur should be based on 

 their needs and condition, because of their im- 

 portance in stock carrying capacity and perform- 

 ance. 



In most cases, mechanical treatment will be 

 necessary to restore their productivity, or even 

 to prevent further degeneration. Where large 

 amounts of flood water are involved, the treat- 

 ments will need to be carefullv engineered. 



Conclusion 



Australia generally lags behind the United 

 States in the application of scientific principles 



Figure 5. — Spinifex sand plain dominated by Triodia basedoioii. 



