14 MONTANA EXPERIMENT STATION BULLETIN 425 



up the Yellowstone River to Miles City is threatened with severe 

 populations. This comprises the area where M. difjerentialis is in- 

 creasing in abundance. Extending out from this is an area of 

 threatening populations which includes most of the drainage of 

 the lower Yellowstone River. Northeastern counties as far west 

 as Phillips County will be in an area of threatening populations. 

 The Triangle area, including Hill, Chouteau, northern Cascade, 

 eastern Teton, and Pondera and southern Toole and Liberty coun- 

 ties, comprises another area where populations are increasing. 

 Threatening areas also exist in parts of Powder River, Rosebud, 

 Big Horn, Yellowstone, Golden Valley, and counties west of the 

 Continental Divide. It seems probable that all counties with or- 

 ganized campaigns will be confronted with more extensive com- 

 paigns in 1945. If drouth conditions should prevail in the wheat- 

 growing sections, extensive damage can be expected unless well 

 organized control campaigns are promptly and extensively carried 

 out. 



MORMON CRICKET CONTROL, 1943-44 



Mormon crickets are not, at the present time, an economic 

 problem in Montana. The last control program was conducted in 

 1942. 



In 1943 a moderate infestation was present in Big Horn Coun- 

 ty east of Pryor on the bench between Hay Creek and Deep 

 Creek, involving an area of about 2500 acres. Another light infes- 

 tation was present southeast of Lodge Grass at the head of Owl 

 and Little Owl creeks. Another moderate infestation was present 

 in Beaverhead County along the Idaho-Montana line, extending 

 from the head of Poison Creek to the head of Shineberger Creek, 

 and comprising an area of about 3600 acres. In neither of these 

 areas was the infestation sufficient in numbers to warrant control. 

 Crickets were also reported as present, but in very small numbers, 

 in northeastern Montana, the Highwood Mountains, and other 

 scattered localities throughout the State. 



In 1944, the infestation in the Pryor Mountain area had in- 

 creased in numbers and in the size of the area infested. No con- 

 centrations were reported,however, which would warrant control 

 operations. No investigation of the Beaverhead was made in 1944 

 but no reports indicating an increase in this area were received. 



More frequent reports and observations of the presence of 

 crickets in small numbers were made in many parts of the State 

 in 1944. Upon the basis of these reports it would appear that cric- 

 ket populations were on the increase but do. not as yet present an 

 economic problem. 



