THE BOLLWORM OR CORN EARWORM. 9 



enables the farmer to destroy many of them by plowing at the proper 

 time. 



Second^ the caterpillars feed for a time on the surface of the 

 leaves before penetrating the tissues of the plant. This is the only 

 time during which the insect can be poisoned successfully. 



Third^ the number of bollworms or earworms increases greatly 

 as the season advances. This indicates a need for hastening the 

 maturity of all crops affected. 



Fourth^ since green corn is preferred as food, it is possible to 

 utilize this to some extent as a trap to protect cotton and other 

 crops. 



It has been found that by modifying slightly the usual farm 

 practices much can be done toward lessening bollworm or corn ear- 

 worm injury. Fortunately these modifications are such as to increase 

 crop production, regardless of the presence of this insect. Another 

 important point is that some of the recommendations for controlling 

 this insect are equally applicable, irrespective of the crop grown. 



FALL AND WINTER PLOWING. 



Probably the most important single step in controlling the boll- 

 worm consists of thorough breaking of the land in which the 

 worms have buried themselves for the winter, at some time during 

 the late fall or winter months. Particular attention should be paid in 

 this respect to the crops which are known to have bollworms devel- 

 oping during the late fall months. The practice of fall and w^inter 

 plowing, aside from bollworm control, is desirable because it con- 

 serves moisture, puts the ground in better condition for planting, and 

 enables the farmer to plant at the proper time the following spring. 



It has been found that the breaking up of the cells in which the 

 insect is spetiding the winter results in the destruction of practically 

 every pupa through the action of cold and moisture. Since the cells 

 of the wintering brood are formed at from 4 to 6 inches beneath the 

 surface, it is important that the plowing be deep enough to reach 

 them. It is desirable to plow or deeply disk the fence rows and other 

 places where bollworms may have fed on various plants. This is also 

 beneficial in destroying eggs of grasshoppers and hibernating places 

 of chinch bugs and other destructive insects. 



CONTROL ON CORN. 



CULTURAL METHODS. 



In addition to the employment of fall and winter plowing, the 

 injury to corn can be reduced somewhat by planting as early in the 

 spring as is compatible with getting the ground into good condition. 

 The corn should be as nearly uniform in age as possible and every 

 effort should be made to hasten growth and maturity. Keeping the 



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