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GRAZING INDICATORS. 

 Average Composition of Plants. 



Relation to climatic cycles. No other factor produces such rapid and 

 striking changes in carrying capacity as does rainfall. The difference in the 

 total yield of the same range in two successive years of dissimilar rainfall may 

 be greater than 100 per cent, and in the wet and dry phase of the same cycle 

 it may be even greater. Such differences are often greatly augmented by the 

 critical overgrazing which is more or less unavoidable during a drought period 

 under, existing methods of management. Since grassland is typically cor- 

 related with summer rainfall, the amount of the latter is at once reflected 

 in the growth of the dominants. A single year of deficient rainfall affects 

 the yield at once by decreasing vegetative growth. At the same time, 



