MODERN WARFARE AGAINST GRASSHOPPERS 465 



MODERN" WARFARE AGAINST GRASSHOPPERS 



By Professor F. L. WASHBURN 



MINNESOTA EXPERIMENT STATION, STATE UNIVERSITY, MINNEAPOLIS 



T N all probability there will never be in the middle west a repetition 

 ■*- of such uneasiness and alarm as prevailed during the early seven- 

 ties in the states of the upper Mississippi and Missouri valleys, on 

 account of the so-called Rocky Mountain grasshopper, Melanoplus 

 {Caloptenus) spretus. Entomologists living in the area bounded by 

 the Rockies on the west and the Mississippi Valley on the east report 

 that for many years they have been unable to collect a baker's dozen of 

 this long-winged locust east of the western plains, which represent 

 occasional breeding grounds of this at one time destructive species, or 

 in the foothills of the Rockies, believed to be the source and permanent 

 breeding grounds of the pest, although it is reported that a few indi- 

 viduals have recently been captured in the Rocky Mountain districts. 

 The passing of this insect may be in slight part due to the settling up 

 of much of the country formerly utilized by them as breeding grounds, 

 either temporarily or permanently. But so suddenly has it disappeared, 

 and so markedly has been the increase of an allied shorter-winged 

 form, M. atlanis (the lesser migratory locust), closely resembling 

 M. spretus, that a suspicion exists that the latter may have been a 

 varietal and, we may say, a sporadic form of the first named. Farmers, 

 however, and others in the region indicated, must rid themselves of 

 the idea that the winged visitor from the Rockies which, years ago, 

 laid waste their fields, is the one grasshopper to be dreaded. Indeed, 

 they are beginning to realize that in the rapid increase of some of our 

 common species, which we may refer to as "native" species, there 

 exists a serious menace to successful farming. Any grasshopper or 

 locust is injurious in proportion to its abundance, and during the last 

 three years a marked increase of a few of our common forms, and the 

 accompanying and yearly increasing injury to crops, constitute a 

 " writing on the wall," as it were, well calculated to rouse citizens from 

 a feeling of absolute security to an appreciation of the need of practical 

 measures of control. This menace is of interest not only to farmers, 

 but naturally also to business men in any community so afflicted, since 

 the business prosperity of a locality depends very largely on the pros- 

 perity of the farmers. 



The farmer living in a neighborhood under complete cultivation, 

 containing but a small amount of unfilled land, has little to fear, but 



VOL. LXXXI. -32 



