THE SMALL GRAINS 



211 



may be sown in a fertile soil later than in a poor soil and 

 in a well-prepared seed bed later than in one poorly pre- 

 pared. The roots must become well established before 

 winter sets in or winterkilling is apt to result. On the 

 other hand, too early sowing may cause plants to 

 " shoot," after which they will be killed by the extreme 

 cold of winter. 



Fig. 91. — Cutting grain with a self-binder. 



The Hessian fly makes its appearance known by attack- 

 ing the volunteer wheat, which comes up after the crop 

 is harvested. When the insect is present in the fields, 

 seeding must be delayed until practically time for frost, 

 for after this time, the eggs are no longer laid. In Kansas 

 and Oklahoma, wheat planted in the first week in October 

 usually escapes injury from the Hessian fly. 



144. Harvesting the Wheat. — The wheat harvest 

 begins in the South in May and moves gradually north- 

 ward, the crop in North Dakota being harvested in August. 



