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MONTANA EXPERIMENT STATION BULLETIN 269 



This amount of money furnished about 200 tons of prepared 

 poisoned bait. Besides this farmers financed their own poisoning 

 operations to the extent of about another 100 tons of bait, making 

 a total of about 300 tons of bait for about 30,000 acres poisoned. 

 This estimate is low for in many districts supplies of crude arsenic 

 and molasses left from previous campaigns were used without definite 

 records of the amounts so consumed. 



Figure 2. — Grasshopper damage in Montana in 1932. Infestations 

 developed in very nearly the exact areas for ^vhich predictions 

 were positive in the 1931 survey. 



The chief species concerned in these outbreaks were the warrior 

 gi-asshopper {Camnula pellucida Scud.) in western Montana; the 

 two-striped {Melanoplus hivittatus Say), lesser migratory (J/, mex- 

 icanus Sauss.), and Packard grasshoppers (M. packardi Scud.), and 

 two-striped grasslioppers in the eastern counties. The differential 

 grasshopper {Melanoplus differentialis Thomas) appeared in eastern 

 Montana (Dawson County) for the first time. It is believed to 

 have flown in rather late in the season from South Dakota. This is 

 the species which, together with the two-striped grasshopper (M. 

 hivittatus Say), has been responsible for much of the Dakota- 



