Figure 4. 



Kochia sedifolia pasture, with myall trees {Acacia sowdenii); grass and other annuals 

 complete with the bluebush which is not growing vigorously. 



cement of the experiment. Myall trees (Acacia sowdenii) and a number of shrubs of 

 minor importance are associated with the bluebush. During drought years the ground 

 between the bushes is devoid of plants, but in seasons of favourable rainfall, herbage 

 and grass provide a sparse to moderate cover. The soil is of an arid calcareous type, 

 with a brown loamy sand surface ; the texture increases gradually to a sandy clay at 

 about 3 feet. The effects of treatments have been measured primarily by weight esti- 

 mates (Woodroffe, 1941) of the amount of edible green forage present in the spring of 

 each year; trends in the numbers and production of bluebush have been used as the 

 main indicators of the results of grazing. Live weights and wool production of the 

 sheep have been recorded. 



For the purpose of the present paper, discussion will be confined to five treat- 

 ments, viz :- 



1. Control with no grazing. 



2. Continuous light grazing at the rate of 24 sheep per square mile. 



3. Continuous moderate grazing at the rate of 48 sheep per square mile. 



134 



