MONTANA INSECT PESTS, 1949 AND 1950 17 



FALSE CHINCH BUGS (Nysius ericae) 



Large numbers of false chinch bugs were reported in the fall 

 of 1950 from weedy areas in Fallon County and from hay fields 

 in Big Horn County. It would be well to be alert for these sucking 

 insect pests in the above areas in 1951. During the biennium this 

 insect was not reported as causing economic damage. 



FIELD CRICKETS (Gryllidae Family) 



These nocturnal feeding insects which are common in grain 

 and alfalfa fields throughout most of the state are normally not 

 numerous enough to be a serious economic factor. Inquiries have 

 been received during the past two years from Carbon, Hill, and 

 Phillips counties, but it is doubtful if these insects were destructive 

 enough to warrant an investment in control measures. 



EARWIGS (Forficula auricularia) 



The relatively recent infestation of European earwigs in the 

 Gallatin Valley has become well established during the past two 

 years, and is rapidly becoming an economic hazard to certain 

 garden produce. These household and garden pests have been 

 numerous over most of western Montana during the last two years 

 and were particularly noticeable in the Ronan area of Lake County. 

 European earwigs are readily controlled by fall and spring applica- 

 tion of 5% chlordane spray while they are in buildings and other 

 protected areas. 



INSECTS DESTRUCTIVE OF FIELD CROPS 



SMALL GRAINS 



CRESTED WHEAT PLANT BUG (Labops hesperus) 



This sucking insect which attacks crested wheat grass is found 

 generally throughout southern Montana. Crested wheat plant bugs 

 were responsible for severe damage to a crested wheat planting 

 in Rosebud County in June of 1949. This is the only known case 

 of economic damage caused by these insects in Montana during 

 the last two years. 



WESTERN WHEAT APHID (Brachycolus tritici) 



The western wheat aphid, a sucking plant louse, was not ob- 

 served or reported in 1949. Cool, damp weather, such as was ex- 

 perienced during the summer of 1950, is generally favorable for 

 the development of most aphids. In 1950 the western wheat aphid 

 was found in parts of Chouteau, Fergus, Musselshell, Broadwater, 

 Stillwater, Yellowstone, and Gallatin counties. These infestations 

 were not general throughout these counties, but tended to be 

 localized in various winter wheat fields and were often spotted 

 in the field affected. Typical malformed winter wheat heads 



