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INSECT PESTS 
GRASSHOPPERS 
During the summer of 193& grasshoppers extended their previous zone 
of severe infestation in the Northern Great Plains and Upper Mississippi 
Valley and pushed southward to Arkansas, Oklahoma, and Texas. Extensive 
crop damage took place in Illinois, Iowa, Kansas, Missouri, Montana, Neb- 
raska, Oklahoma, and Wyoming. The value of crops destroyed in these 
States has "been estimated at approximately $80,000,000. Less extensive 
crop damage occurred in Arkansas, California, Colorado, Minnesota, Mich- 
igan, North Dakota, Oregon, South Dakota, Texas, Utah, and Wisconsin. In 
addition to losses in cultivated crops, the hoppers severely injured range 
grass and pastures in Montana, Nebraska, North Dakota, South Dakota, Utah, 
and Wyoming. 
After the coldest winter on record (the mean monthly temperature 
for North Dakota for February 193& was -1^°P. ) , the weather over the 
grasshopper- infested area suddenly "broke hot and dry about May 1, and 
continued on into the hottest and driest summer on record. Daily maxi- 
mum temperatures of above 100° occurred in many parts of the territory 
during about 17 days in June, 25 days in July, 25 days in August, and 
even a day or so during the first week of September. Maximum air tem- 
peratures "broke all-time records from 118 c to 121°. Some areas went 
without a drop of moisture for over 100 consecutive days. 
Hatching was first recordei on April 20 at Huntley, Mont. In 
other parts of the area — the Dakctas, Iowa, Nebraska, Michigan, Wis- 
cons in, Kansas, and Colorado — first hatching occurred from May 1 to 
May 18. Because of the hot, dry weather, the nymphs developed rapidly 
and depredations started early. Adults of Me Ian op 1 us bivittatus Say 
and M. mexicanus Sauss. were taken early in June in Iowa and Montana, 
most individuals becoming adult by June 15. On the other hand, in 
Oklahoma most of the M. bivittatus and M. different ialis Thos. did 
not reach the adult stage until after July 1. Active control measures 
to protect crops were necessary in the Yellowstone Valley, M nt., by 
the first week of May and in other States by the 15th. May rains in 
Iowa, Nebraska, Kansas, and Oklahoma held the hoppers in check and 
allowed most of the small grain to escape thoir ravages. 
Nymphs first appeared in the alfalfa, grain, and pasture lands. 
When these were cut or when they had dried up, the hoppers moved into 
the corn and other late crops. This general movement took place the 
last week of June. As the intense heat continued in July, the next 
move was to take to the trees, shrubs, fence posts, telephone and tel- 
egraph poles, and, where there were nc trers, to tall weeds. The only 
available nr isture was in the bark and leaves of the tre^s and shrubs, 
which the roasting hoppers barked and defoliated. In parts of Kansas, 
Nebraska, and Oklahoma the Osage-orange is used for hedge fences, and 
these were stripped bare. Many orchards suffered. Along water courses 
