8 MONTANA EXPERIMENT STATION BULLETIN 425 



Federally Financed Control In 1943 



The fall of 1943 witnessed a co-operative attempt by county, 

 State and Federal representatives to reduce an incipient grass- 

 hopper outbreak by a concerted program of fall bait applications 

 to reduce egg laying. Yellowstone County was selected for the 

 effort. It was estimated September first that 50-75 percent of 

 the grasshoppers in the County were located in the weedy en- 

 vironment found in field margins, roadsides, railroad rights-of-way 

 and along irrigation and drainage canals. This concentration in the 

 margins was due to the extended drouth during the summer, 

 which matured crops early and left weedy margins the main 

 source of green forage, and the natural tendency of M. bivittatus 

 to lay its eggs in these habitats. If these concentrated popula- 

 tions could be destroyed before many eggs were laid, the infesta- 

 tion the following season would be greatly reduced. Upon this 

 basis an extensive marginal baiting program was organized. The 

 Bureau of Entomology and Plant Quarantine and Yellowstone 

 County pooled mixing and spreading equipment, including a new 

 type blower spreader, an airplane, and various traction and power- 

 operated spreaders. Countv, State and Federal agencies provided 

 supervisory personnel and labor. The Northern Pacific, Great 

 Northern, and Chicago, Burlington and Quincy railroads sup- 

 plied equipment and personnel for baiting their rights-of-way 

 and cooperated whole-heartedly in ronducting the program. The 

 Wyoming State Entomologist, Mr. Tom Snipes, also cooperated 

 and participated in the work. Prompt and efficient organiza- 

 tion and conduct of the camoaign resulted in the baiting of 3,265 

 miles of roadside margins, 271 miles of railroad rights-of-way and 

 412 miles of irrigation and drainage canal margins. 



Success of the campaign was demonstrated by the kills ob- 

 tained, the reduction in eggs laid, and the reduced population in 

 the baited area in the spring of 1944. 



1944 Season 



The 1943 egg survey indicated light to threatening populations 

 in parts of the Yellowstone River drainage, the Triangle area and 

 Lake and Sanders counties. Reports received indicated that threat- 

 ening infestations also existed in the other western counties. (Fig- 

 ure 2) . In the spring of 1944 surveys and contacts with county 

 officials indicated growing alarm in these counties and special 

 efforts were made to organize these counties for effective control 

 campaigns. 



The 1944 season began with drouth conditions existing over 

 the entire State, and severe drouth in Toole, Glacier, and counties 

 west of the Divide. This condition still existed when the first 'hop- 

 pers hatched during the week of May 7. With drouth continuing 



