1919.1 RAINFALL AND FliOGHOPFEE BLIGHT. 167 



It is common knowledge that plants in a water-logged soil are the 

 first to suffer from a dry spell, for although the moisture may be present 

 only a few inches away, the root s.vstem of the plant, confined by lack 

 of air to the top layer of the soil, has not enough reserve strength to 

 withstand the sudden adverse conditions and cannot reach the necessary 

 moisture. 



SUMMARY. 



(1.) Alternation of wet and dry periods daring the growth of the 

 sugar cane is shown to be an important factor in determining tlie 

 prevalence of " blight." 



(2.) A long dry season followed by unusually heavy rains in June oi- 

 July, is frequently connected with wide-spread blight. 



(3.) The most important climatic condition however, appears to be 

 the severity of the " Indian Summer," a dry period in September or 

 October. A severe Indian Summer is a general condition both of 

 localities damaged by blight in one year and of years of wide-spread 

 blight in one locality. 



(4.) Blight could be reduced, irrespective of its first cause, by 

 getting the field in a condition to lessen the effects of excessive 

 moisture and drought. 



(5.) Better drainage is the obvious agricultural method that will 

 help to bring about these conditions. 



August 1919. 



