192 



INSECTS AFFECTING FIELD CROPS 



The young bugs are 

 brownish black. They 



yellowish or 

 grow darker 



of the legs are reddish, 

 bright red, marked with 

 with age. 



Life History. This insect passes the winter hi the adult stage 

 under shocks of corn or under leaves in the woods or under rubbish 

 of any sort in the fields. It comes out as soon as warm weather 

 arrives in the spring, generally early in May, and flies to wheat, 

 rye, barley, or grass lands. Here the female deposits eggs upon the 

 ground close to the roots of the plants or upon the bases and roots 

 themselves. About 500 eggs are laid during a period of ten to 

 fifteen days. These hatch in two weeks, the nymphs beginning 



at once to feed like the adults by 

 sucking the juices from the young 

 plants. There are generally two 

 broods. Since, however, the eggs 

 laid by one female are not all de- 

 posited at once, in the latter part of 

 the summer insects of all stages are 

 observed. From fifty-seven to sixty 

 days are required for the life cycle of 

 one generation. 



Injury. Although grains and 

 grasses are weakened by attack, the 

 worst injury occurs upon corn, for 

 corn is sought aftes the grasses or 

 grains ripen. Frequently one ob- 

 serves in the field a vast army of 

 chinch bugs of all ages migrating 

 from grain field to corn field, appear- 

 ing to know instinctively the direc- 

 tion in which their chosen food lies. 

 Control We have not as yet learned to successfully control 

 this pest in wheat fields, and all our efforts are directed against 

 protecting the outer rows of corn. While the Hessian fly prefers 

 the moist weather, rams destroy young chinch bugs and encourage 

 the growth of parasitic fungi (Fig. 211). Unlike the Hessian fly, 

 therefore, the chinch bug prefers and revels in the hot sun. It is 

 a frequent practice to interpose some barrier between the advancing 

 bugs and the corn fields. A deep furrow with the steep side toward 

 the corn may be plowed if the bugs are observed in time. The 

 insects which gather in the furrow may be destroyed with kerosene 



FIG. 211. Diseased chinch bug. 

 (Lugger.) 



