PLANT MORPHOGENESIS FOR SCIENTIFIC MANAGEMENT OF RANGE RESOURCES 



199 



associated with the large river systems. All of 

 these situations are highly productive. 



Spinifex Grassland 



This characteristic grassland occurs extensively 

 on sand plains and dune fields and to a lesser 

 extent on sandy red earths. Spinifex consists of 

 species of Triodia and Pletrachne. All of the 

 species are low in palatability, utilization, and 

 productivity {26). Consequently, overgrazing 

 is rare. Because of the low productivity, the 

 range type is used only when it is adjacent to 

 land with higher productive capacity. 



Mountains And Hills 



These areas are generally stony and steep, and 

 are not important as a grazing resource. They 

 support limited grass, herbage, and scattered 

 timber and are occupied only because of prox- 

 imity to better lands. Water is rarely provided 

 within the hills. Where the hills are extensive, 

 stock graze them only when temporary water 

 is available. Localized deterioration has occurred 

 as a result of timber cutting for fuel or mining 

 purposes. 



An estimation of the present condition of the 

 Australian rangelands is presented in table 1. 

 Broadly, the position is that the grasslands and 

 the spinifex grasslands are in reasonably good 

 condition in comparison with the pristine state. 

 Damage is mainly a loss of palatable species 

 without serious invasion by inedible species. Res- 



toration appears to be relatively simple. The 

 mountains and hills, the low woodlands, and the 

 flood plains and alluvial fans are moderately 

 degraded, with 10 percent of their total area 

 being in a critical state of deterioration. 



The shrublands have deteriorated to the great- 

 est extent, due to the susceptibility to grazing of 

 the perennial shrubs and to the erosive nature 

 of the soil. Twenty-five percent of the total area 

 has either lost the shrub layer or deteriorated to 

 a scalded state. At the latter stage, production is 

 nil and restoration is difficult and expensive. The 

 major cause of deterioration has been excessive 

 grazing pressure in the early years of settlement. 

 Severe droughts have manifested the problem. 



Past And Present Grazing Practice 



Grazing practice throughout arid and semiarid 

 Australia has been, and still is, simple. This ap- 

 plies where both sheep and cattle are grazed. 



Sheep holdings are broken up into approxi- 

 mately 12 paddocks. Cattle grazing is more ex- 

 tensive, often with little more than boundary 

 fencing. In sheep areas, the majority of the land 

 is commanded by water, so that sheep do not 

 have to travel beyond 5 to 6 kilometers for 

 water. Cattle country is less well developed, and 

 extensive areas are unwatered. During drought 

 periods, relief has been obtained by establishing a 

 new watering point on land that was previously 

 beyond the grazing reach of cattle. This drought 

 tactic obviouslv is limited. 



Table 1. — Percentage of rangeland types in particular degeneration classes 

 [The present pastoral value in relation to expected pristine condition] 



Rangeland 

 types 



Percentage of degeneration 



Little or 









none 



Minor 



Moderate 



Severe 



(80-100 percent) 



(60-80 percent) 



(40-60 percent) 



(<40 percent) 



30 



55 



15 



Negligible 



10 



25 



40 



25 



40 



30 



20 



10 



40 



30 



20 



10 



70 



20 



5 



5 



50 



20 



L>0 



in 



Grasslands 



Shrublands 



Low woodlands 



Flood plains and alluvial fans 



Spinifex grasslands 



Mountains and hills 



Source: After Newman and Condon (20). 



