SOME INSECTS ATTACKING THE STEMS OF GROWING 

 WHEAT, PtYE, BARLEY, AND OATS. 



INTRODUCTION. 



Throughout the United States, where the smaller cereal g-rains — 

 wheat, rj^e, barley, and oats — are to any considerable extent cultivated, 

 a multitude of injuries to growing wheat are charged by the average 

 farmer to the Hessian fly; whereas, in many cases these ravages are 

 really the work of insects whose habits differ greatly from those of 

 that insect. Indeed, some of them are not flies at all, and even 

 where the ravages are caused by flies, these are not necessarily the 

 Hessian fly, and the same remedial and preventive measures that are 

 applicable to this notorious wheat pest may not be at all eft'ective 

 against them. In fact, it is with the hope of enabling the farmer, as 

 also the economic student, to distinguish between some of the chief 

 insect enemies of cereal grains, and especially between many of them 

 and the Hessian fly, that this publication has been prepared. 



In the following pages the author has restricted himself to the con- 

 sideration of two groups of grain-affecting insects, the one composed 

 of true flies, and the other not, though both during their developmental 

 stages live and thrive within the stems of wheat, and to some extent 

 within those of the growing grasses as well. Indeed, as a whole, they 

 were doubtless primarily grass feeders, and their grain-attacking 

 habits, being of more recent origin, brought about by the changed con- 

 ditions of their natural food supply, consequent upon the influences of 

 advancing civilization, may be looked upon as a modification of their 

 original methods of living. 



While this variety of food plants, including the wild grasses, as well 

 as the cultivated grains, probably has the effect of more generally 

 diffusing some of these insects, thus rendering serious outbreaks of 

 less frequent occurrence, the other phase of the problem is that though 

 the farmer might exterminate them from his fields, they would still 

 inhabit the grass lands and from there continually send a fresh supply 

 of colonists into his fields to repopulate them. But, again, this has 

 its redeeming features, as it enables the grain grower, in some cases, 

 to* meet his enemies in the grasses and there fight them to better 

 advantage to himself than in his cultivated fields. The Hessian fly is 



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