REPORT OF THE STATIC ENTOMOLOGIST \<)\() 79 



at least, serve as a guide as to the advisability of making more or 

 less close examinations to determine whether grassland in which 

 susceptible crops, such as potatoes, would normally be planted, 

 should be vsed for such purposes or the rotation changed and some 

 crop not liable to injury, such as rye, be substituted. 



White grub robber fly (Promachus f i t ch i i 0. S.). The 

 stout white maggots of this efficient natural enemy have been under 

 observation for four seasons and conditions this year almost dupli- 

 cate those observed in 19 13, namely, a considerable abundance 

 of these maggots in sodland which had been so injured by white 

 grubs the preceding year that the grass was practically killed. Areas 

 where these maggots were most abundant were characterized by 

 a scarcity of white grubs, and conversely these pests of the farmer 

 were more numerous in sodland where the predaceous maggot 

 was relatively scarce. Conditions typical of this section are embodied 

 in the following notes. 



An examination May 8th of grass sod on the farm of Mr F. B. 

 Smith, Schodack, revealed a moderate number of nearly full-grown 

 white grubs, some decidedly yellowish and an almost equal number 

 of the predaceous maggots of Promachus. 



An investigation June 12 th of a large plowed field belonging 

 to Mr G. A. Hoyt, also of Schodack, resulted in finding very few 

 full-grown white grubs, several half -grown white grubs and a number 

 of Promachus larvae. This field was so badly infested by white 

 grubs the previous year that considerable areas were torn up with 

 a horserake and yet at the present time there are very few white 

 grubs and considerable numbers of the maggots. There is no 

 escaping the conclusion that Promachus larvae have been an 

 important factor in controlling the pest, which is supported by 

 the unusual abundance of the parent insects or robber flies. 



The true character of these beneficial maggots should be more 

 generally recognized. They are, when full grown, about an inch 

 long, one-fourth of an inch in diameter, moderately firm or rather 

 horny in texture, anl invariably lay in a straight or nearly straight 

 position and present a marked contrast to the half-curled, stouter 

 and relatively shorter white grubs which, as most farmers know, 

 lay upon their side. An abundance of the maggots, as previously 

 stated, means relatively few white grubs and materially lessens 

 the danger of injury from this destructive pest. 



Grasshoppers (Melanoplus atlanis Riley and others).. 

 The season of 19 16 opened with the appearance of many small 

 grasshoppers here and there in localities where these pests were 



