32 DEPAETMENT BULLETIlsT 779. 



MISCKT.T.ANEOUS ENEMIES. 



The Rocky Mountain toad {Bufo lentiginosus woodhousei) has 

 been recorded by the Biological Survey as feeding upon various 

 species of Chlorochroa. 



A half -grown chicken devoured 8 adults during a single day, when 

 placed in a large outdoor cage with these insects. It has been com- 

 monly reported by farmers that a diet of grain bugs often kills 

 barnyard fowls, but these reports have not been verified. 



CONTROL METHODS. 



DESTRUCTION OF HIBERNATING QUARTERS. 



The obvious method for controlling the grain bug is the destruc- 

 tion of the adults when they are concentrated in their hibernating 

 quarters. This is best accomplished in the late autumn, during the 

 winter, or in the early spring by plowing under or burning all weeds 

 and rubbish in and about cultivated fields. This applies particularly 

 to the dead Russian thistle in abandoned fields and along irrigation 

 ditches, check ridges, and fence rows ; in fact, all locations where the 

 accumulations of weeds or rubbish afford suitable hibernating quar- 

 ters. Even in the large-scale farming operations which predominate 

 throughout most of the territory infested by the insect, it is possible 

 to carry out these measures of control as a good farming practice 

 which contributes to the destruction of weeds and of various species 

 of noxious insects. Much of the local infestation results from hiber- 

 nating adults that wintered in the same field or its vicinity and which 

 could have been destroyed by the farmer with an expenditure of very 

 little additional labor. In many instances, however, the grain bug 

 adults migrate from considerable distances and this circumstance 

 necessitates a systematic clean-up community campaign in badly in- 

 fested areas. Objections often are offered to control measures simi- 

 lar to the foregoing, because of the time and expense involved in 

 their application, but it must be borne in mind that any extra efforts 

 required to prevent insect depredations are repaid manyfold in the 

 increased production of the crops. The measures recommended here- 

 in for the control of the grain bug should be included in good farm 

 practice at any event and can be carried out during a time when 

 farm labor and equipment ordinarily are idle. 



TRAP CROPS. 



Early in the season the immature stages of the first generation of 

 the grain bug are concentrated on the tender plants of Russian thistle 

 and other native plants growing in the waste areas of cultivated fields. 

 At this time the multiplication of the species may be restricted greatly 

 by spraying these areas with a strong insecticide or chemical, thus 

 killing the insects and their obnoxious food plants in one operation. 



