Some Special Injurious Insects 169 



at night; usually in the afternoons. In wet weather the 

 corn may be protected by a line of tar or crude oil. Chinch 

 bugs pass the winter in tufts of grass (Fig. 105). 



236. The Hessian Fly is a native of Europe and is 

 supposed to have been introduced into America by the 

 Hessian soldiers in the Revolutionary War; hence the 

 name. Next to the chinch bug it is the most serious in- 

 sect pest of the wheat crop. It has been found that 

 the damage can be 

 largely prevented by 

 plowing under the 

 stubble j ust after har- 

 vest and destroying 

 the volunteer wheat 

 in summer. The 



Stubble harbors the Fig. 106. Hessian fly. a, adult, about three times 



i j rir oo/3l natural size; 6, pupa or "flaxseed" stage, slightly 



pupal Stage. l"| ZZO.J enlarged; c, larvae or maggots, enlarged. After 



T- , i , Washburn. 



If turned under 



deeply it prevents many of the flies from escaping, and thus 



reduces the late " summer crop" of flies and maggots. 



The adult Hessian fly may be seen in infested fields 

 in late summer or early spring. It is a yellowish brown 

 colored, long-legged, gnat-like insect (Fig. 106). The 

 female lays slender, oval, reddish eggs, lengthwise the 

 grooves on the upper side of the leaves. These eggs, just 

 large enough to be seen with the unaided eye, hatch out 

 tiny reddish larvae that wriggle down to the stem under 

 the leaf sheath wiiere they feed and grow. The maggots 

 soon lose their reddish color, turn w r hite, form a flaxseed- 

 like brown pupa before cold weather. Some of the pupae 

 hatch out, producing the " spring crop" of flies. Most of 

 the pupae, however, remain dormant on the stubble and 

 develop the late "summer brood" of flies, which in turn 



