168 THE BOOK OF WHEAT 



average annual loss at 10 per cent. In 1903 the loss in southern 

 Wisconsin was 50 per cent and in South Carolina 30 per cent. 

 In 1904 the wheat crop of Minnesota and the Dakotas was 

 most promising, but in a few days it was so damaged by rust 

 that experts estimated the loss for the three states at 30,000,000 

 bushels, and the wheat that was produced in many instances 

 weighed only from 36 to 48 pounds per measured bushel. Many 

 fields were not harvested. Twenty million dollars seems a rea- 

 sonable estimate for the average yearly loss from wheat rust 

 in the United States. Immense annual losses are suffered by 

 the Australian, Russian and Argentine wheat fields. In some 

 years the loss in England is 50 per cent. Nor is this the only 

 form of loss that must be attributed to rust, for it is one of 

 the chief hindrances that entirely prevent the growing of 

 wheat in parts of certain moist warm countries, such as China 

 and Japan. 



Remedies. Thus far rust has baffled every attempt at a 

 remedy. Fungicides and spraying have been experimented with, 

 but indirect methods are the only ones that have proved of 

 any aid in the combat. All conditions are helpful that tend to 

 mature the wheat crop before the rust becomes abundant. 

 Fields should be properly drained. Good clean seed of a pure 

 variety and of the best germinating powers should be sown 

 in soil properly prepared. The seeding should be early, and the 

 crop should be kept free from smut and weeds. All of these 

 things strengthen the wheat plant and hasten its growth. Ro- 

 tation of crops is also advantageous. Wild grasses and weeds 

 of the roadsides should be mown, and all barberry shrubs should 

 be killed. The fields should be kept free from volunteer grains. 

 The line of demarcation between the winter and spring wheat 

 belts should be sharply drawn, for the winter wheat, ripening 

 early, develops rust in such abundance that it will greatly 

 injure the later spring wheat. The early maturity of winter 

 varieties generally enables them to escape serious damage. 



One of the most hopeful phases of the question is that some 

 varieties of wheat are quite rust resistant. The different rusts 

 are each more easily resisted by certain varieties of wheat. 

 Thousands of varieties have been tested and bred to secure 

 rust resistance. None are absolutely rust proof. "So far as 

 the ordinary wheats are concerned, the resistant varieties are. 



