THE FAMILY OF GRASSES 349 



The attempt has been made many times to 

 estimate the average loss that results to the 

 grain growers of the world and hence, of 

 course, ultimately to the consumers in every 

 rank of life from the attacks of this micro- 

 scopic but all-powerful enemy. It is conserva- 

 tively estimated, for example, that the loss to the 

 wheat growers of Australia is from ten to fifteen 

 million dollars a year. Yet Australia is rela- 

 tively free from the pest. In an old wheat coun- 

 try like Prussia, where the rust has gained a 

 more secure foothold, the losses are enormously 

 greater. 



It has been estimated that in a single 

 season the loss from rust on the various small 

 grains in Prussia alone was not less than 

 $100,000,000. 



In America the losses from rust vary greatly 

 from year to year; but there is no season when 

 the destruction wrought by this pest would not 

 be calculable in millions of dollars. There are 

 exceptional seasons when in entire regions the 

 wheat crop is almost totally destroyed and other 

 seasons in which the losses amount to a high per- 

 centage of the total crop. 



All in all, the microscopic uredospore must 

 be listed among the most important and most 

 menacing enemies of our race. 



