Small Grains 143 



66. Insects of wheat fields. The Hessian fly and chinch- 

 bug are the most injurious insect pests to the wheat. 



The Hessian fly is a blackish insect about one-tenth inch in 

 length. The larvae eat the stems of young wheat plants, caus- 

 ing them to tumble over. The methods of controlling this 

 pest are summarized by F. M. Webster in Farmers' Bulletin 

 641: 



" In the fall- wheat-growing sections sow the best of seed 

 in thoroughly prepared, fertile soil after the major portion of 

 the fall brood has made its appearance and passed out of 

 existence, and, if possible, sow on ground not devoted to wheat 

 the preceding year. 



" In the spring- wheat section late seeding will not apply. It 

 seems likely, on the contrary, that the earlier it is sown in 

 spring the less it will suffer from the Hessian fly. But good 

 seed and a well-prepared, fertile soil are as essential there as 

 elsewhere." 



The chinch-bug hibernates during the winter in grass or 

 under piles of weeds, trash, and rubbish and in the spring the 

 females fly to wheat fields to lay eggs on the base of the plants. 

 These eggs hatch in about twenty days and the larvae feed on 

 the wheat. They live on the wheat until it is harvested, when 

 they migrate to corn or oats. The adults have wings, but 

 they travel on foot from the wheat fields. This fact makes it 

 possible to use barriers, as explained elsewhere, in protecting 

 the corn or the oat fields. The insects that reach these fields 

 lay eggs there and a second brood hatches. The adults of 

 this brood fly to grass land and rubbish piles and remain there 

 during the winter. The control of the pest in wheat fields is 

 accomplished by burning rubbish piles early in the spring be- 

 fore the adults lay their eggs. 



67. Fungous diseases of wheat. Smuts, rusts, and scab 

 are fungous diseases that attack wheat. 



Smut. Two kinds, loose smut and stinking smut, are de- 

 structive to wheat (Figs. 53 and 54). Loose smut destroys 



