224 



STATE BOARD OP AGRICULTURE. 



The most prolific source of infestation is the practice of fall, top dress- 

 ing with fresh barn-vard manure before wheat. This furnishes the ideal 

 great difiQcuIty in devising practices to at least modify the difficulty, 

 conditions from the standpoint of the insect. Furthermore, top dress- 

 ing near a field of young wheat offers very slight difficult^' to the insects, 

 for they are good fliers if small. The best practice of all is to let the 

 manure lie until spring and to get it thoroughly soaked with the liquids 

 of the stable, and then to plow this under not too near the wheat field. 

 When joint-Avorms are present in very large numbers it is well to avoid 

 keeping over more straw than is necessary for bedding or which will 

 be used up in other ways before spring. Always burn the short woody 

 segments which contain immature larvae and pupae. When using straw 

 from infested fields, plow deeply if in the fall and harrow in the spring, 



Fig. 23. Swellings made by wheat Joint-worms in straw; enlarged (Original). 



for the little creatures can get out unless well covered. 



Place new wheat fields at a distance from the old ones and plow 

 directly after harvest unless seeded with clover. 



Be sure to difl'erentiate between the joint-worm and the Hessian-fly 

 for the treatment of the two pests is not identical by any means. If 

 there is room for doubt, send in specimens to the writer. 



