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DOMINANT SPECIES BY STATES 
Only a few of the most important species, selected because of their 
greater abundance and economic importance, will be discussed. 
North Dakota 
The dominant and most important grasshoppers in this State were 
Melanoplus mexicanus Sauss. and Camnula pellucida Scudd. The former was 
abundant in the western part of the State, reaching its peak in the northwest- 
ern district (district 2) where it composed 64.8 percent of the total number 
of grasshoppers collected in small grain. It was also a major species in 
flax (27 to 41 percent), abundant in corn ( 14 to 26 percent), and numerous in 
grasslands ( 14 to 25 percent). Camnula pellucida was most abundant in eastern 
and northeastern North Dakota (district 1), where it formed over half the 
grasshopper population along roadsides (77« D percent) and in small grain (54 
percent). Although abundant in the middle and western portions of the State, 
it constituted less than 10 percent of the total number of grasshoppers col- 
lected. Melanoplus femur-rubrum D e G. was next in abundance in cropped 
fields. In alfalfa it composed from 15 to 36 percent of the total number of 
grasshoppers, in flax 20 to 25 percent, and was numerous in corn and small 
grain. M. packardii Scudd. and Ageneotettix deorum Scudd. were also fairly- 
abundant throughout the entire State. 
Two species of grasshoppers of major importance in past outbreaks have 
now greatly decreased in numbers. These are Melanoplus bivittatus Say and M. 
differentialis Thos. M. bivittatus was most abundant in the eastern part of 
the State. M. differentialis , formerly numerous in the southern and south- 
western portions, has almost disappeared. This change is probably due to 
recent extreme heat and drought, Sggs of M, differentialis have been known 
to dry out under such circumstances, possibly because they are laid in the 
crowns of grass clumps close to the soil surface. Both of these species have 
a distinct preference for succulent food and can; ot live through extreme 
drought • 
In the grasslands Agene o tettix deorum Scudd., M estobregma kiowa Thos,, 
Opeia obscura Thos, , Fhlibostroma q uadrimaculatum Thos. , Melanoplus infantilis 
Scudd,, and Encoptolorhu s costalis Scudd. were abundant. Together with M. 
mexi canus and Camnula pelluc ida they were the species of economic importance 
in the range and pasture lands. 
South Dakota 
Most of the crops in South Dakota were destroyed by drought and were 
replaced by Russian-thistle. In the small grain that was left Melanoplus 
mexicanus was the dominant species, ranging from 24 percent of the total 
population in the northeastern part (district 1) to Go percent in the central 
part (district 3)» No other species was nearly so abundant. In alfalfa in 
the central part (district 3) and .the western part (district 4) » i-t constituted 
79 percent of the total number. Melanoplus b ivittatus and M. di fferentialis , 
which were responsible in 1931 *" or the destruction of crops in a ^0, 000- 
square mile area ran only from 2 to 8 percent in all but the southeastern part 
