WHEAT WEEDS, INSECTS, DISEASES 337 



Burning the wheat stubble. It has been noticed that the 

 second brood often develops in the lower joints of the 

 wheat, being left in the stubble at harvest, mostly in 

 the flaxseed stage. (3) Plowing under stubble, and subse- 

 quently rolling it to prevent any maturing adults from 

 escaping. (4) Rotation of crops. 



414. Chinch-bugs (Blissus leucopterus) and weevils. 

 The chinch-bug is responsible for an enormous annual loss 

 to the wheat crop. This pest is described and certain reme- 

 dial measures are outlined in the chapter on insect enemies 

 of corn. As the chinch bugs hibernate in old grass and rub- 

 bish during the winter months, the importance of burning 

 over all waste land places where they would likely find pro- 

 tection cannot be too strongly emphasized. Also the early 

 planting of such crops as millet, or spring wheat to attract 

 the chinch-bugs in their early flight is recommended by 

 many. After these trap-crops become infested they are 

 plowed under. 



Weevils often attack wheat in the shock, stack or bin. 

 In the two former cases no effective treatment can be 

 given. The wheat should be thrashed as early as pos- 

 sible, and the grain placed in tightly constructed, closely 

 covered bins and fumigated with vapors of carbon- 

 disulfide. One pound of carbon-disulfide will treat 30 

 bushels of wheat (see chapter on Insect Enemies of Corn, 

 p. 270). 



415. Fungous diseases. Four fungous diseases cause 

 serious injury to wheat. Of these four diseases, two are 

 rusts, and two are smuts. One form of rust, Puccinia 

 rubigo-vera, occurs principally on the leaves and is 

 known as the early orange leaf-rust. The other form, 

 Puccinia graminis, affects principally the stems and is 

 known as the late stem-rust. There is no treatment 



