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MONTANA 
All of the collections in this State were made in that portion east 
of the Continental Divide. It is in the short-grass area which is subdivided 
for the State as follows: 
1 . Grama and western needlegrass : 
Part of extreme east-central and extreme northeastern portions. 
2. Western wheatgrass a n d sagebrush : , ; 
Large area extending diagonally frpn northwest to southeast through 
eastern half. 
3. Grama grass: 
General eastern two -thirds of State. 
4. Grama grass and mountain sage : 
Along eastern front of the mountains. The chief crops are small 
grains and alfalfa and there are large tracts of grazing lands that have 
"been severely damaged during the last outbreak. 
There were 10,401 specimens in the Montana collections, representing 
42 species in 10 habitats. The distribution is given for all environments 
and the 5 most important species are listed for each habitat. Melr.noplus 
mexicanus is still the dominant species in most places. In 1934 it was also 
the dominant species on the rangeland forming from 7 to 45 percent of the 
population. In 1935 M. mexicanus was fifth in abundance at 9 percent of the 
population. Cordillacris crenulata Bmn, Mestofrresmn kiowa , and Ageneotettix 
deorum were the dominant species this past season. 
Infestations have shifted from the northern counties to the Yellowstone 
Valley, where the worst outbreaks occurred last summer. For 10 years — 1923 
to 1934— this valley had been practically free from grasshopper trouble. 
