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NEBEASKA 
This is the fovxrth year in which collections have "been made 
in this State, and 24,363 specimens , including 54 species, were 
collected in 10 major environments. Eor the collections as a 
whole, Melanoplus mexicanus was dominant, with M. differentialis 
and M,. hivittatus of equal importance in second and third places 
and Melanoplus femur-rutrum fourth. In the upland and sand-hill 
grasslands, Ageneotettix deorum was the most numerous, whereas in 
the iDottom-land grasses M . f emur-rutrum was dominant. This indicates 
a decided reduction of M. mexicanus on the range land, where it was 
the dominant species in 1938. In fact, the relative abundance of 
M. mexicanus has fallen off in all the environments. Eor instance, 
in 1938 it was dominant in. all of 7 habitats included in the 
collections, forming from 29 to 46 percent of the total number of 
specimens collected in these places and 32 percent of the total 
number collected in the State. In 1939 it was dominant in only 4 
out of the 9 habitats included in the collections, forming in these 
4 habitats from 20 to 37 percent of the total number collected in 
these environments and 25 percent of the total number collected in 
the State. On the other hand, M. differentialis and M. bivittatus 
have increased in relative abundance but not necessarily in actual 
numbers. Therefore, there is no doubt that M, mexicanus has 
decreased in importance in Nebraska. 
The largest areas of severe infestation extend diagonally 
across the eastern third of the State, from the northeast to the 
southv/est. These infestations are made up largely of M. differ- 
entialis and M. bivittatus as far west as the western edge of 
Valley, Sherman, Buffalo, Kearney, and Eranklin Counties. They 
occur in sorghum and corn stubble, field margins, alfalfa, and 
small-grain stubble. In the south-central and central parts of the 
State the infestations are lighter and of a mixed population, with 
M. mexicanus becoming more important to the westward. In the 
Panhandle area, where M. mexicanus was numerous in 1939, the egg 
survey showed that infestations had decreased. 
