244 - 
SOUTH DAKOTA 
All of the collections in South Dakota were made in the short-grass 
region. There are five types of association occurring in this area-: 
1« Gran a and western needlegrass : 
Ea.st of the Missouri and north of the Moreau Rivers. 
2. Western T7hea.tgrr,ss : 
Most of the area south of the Moreau River and west of the Missouri 
River. 
3. Grama-buff alo grass : 
A strip ea.st and west south of the White River and west of the 
Missouri River. 
4. Western whea.tgra.ss and sagebrush : 
Extreme northwestern portion in foothills. 
5. Grama grass : 
Also extreme northwestern portion on plains. 
Most of the collecting was restricted to places other than cultivated 
crops. There were no collections in corn and only a small percentage 
(3- percent) in small grains. The bulk of the specimens cane from the 
native grasslands; therefore, any statements regarding relative abundance 
of the different species must be modified by this fact. 
A total of 2, '741 specimens were taken, representing 47 species. 
The dominant species in the whole lot were Ageneotettix deorum and Mestobregna 
kiowa , each equaling about 19 percent of the total number collected. 
Melanp-plus mexicanus ranks third, at approximately 13 percent. 
M. bivittatus and M. diff erentialis were still not very abundant after 
the drought, which decimated their numbers; however, observation showed that 
these two species are building up again in the cultivated crops along river 
courses. 
In 1934 M. mexicanus was the dominant species in this part of South 
Dakota, but this year it has fallen to third place. Strange to say, 
Mestobregma kiowa was the most numerous of all species in alfalfa, constitut- 
ing 42 percent. These collections were made in September when the alfalfa 
was short and dry. In 1934 M. mexicanus constituted from 40 to 80 percent 
of the populations in alfalfa in this area, but in 1935, only 7 percent. 
Threatening infestations were found all along the river courses in the 
central and western parts of the State. The worst infestations were along 
the Missouri River bottom in Hughes County. 
