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in groves and shelterbelts, the willows, poplars, mulberries, and even 
elms and other trees were defoliated, fields of IE-foot corn were made 
to look like forests of fishing pol<~s. In Oklahoma one-tenth of the 
cotton crop was damaged "by July 1. 
Careful observations have shown that the optimum air tempera- 
tures for activity on the ground are "between 75 an( l ^5 F« with surface- 
soil temperatures under 113 . Above these temperatures the hoppers 
either take to the air or roost in the shade as high off the ground as 
possible. With air temperatures this past summer remaining above 
30 for the greater part of the day and for day after day, it is no 
w onder that the pests took to the trees and did such spectacular damage. 
Over the whole area, oviposition was quite erratic. In north- 
western Iowa, Melanopl us bivittatus had completed its life cycle and 
laid its egi^s by August 10. M. mexic a nus laid its eggs early enough 
over a large part of the area to produce a partial second generation. 
In eastern Nebraska and western Iowa this second generation hatched 
about the last week of August. This same phenomena was observed last 
year in a number of places, but seemed more general this year. In 
Oklahoma, M. differential is was still congregated in the trees, shrubs, 
and tall we^ds on September 18, when few eg ; ;s had been deposited. 
Where rains had occurred 2 weeks before this date, egglaying was well 
started. In a large part of this area the first moisture for all sum- 
mer came in a general downpour on September lS-lS. In these dry areas 
no egg deposition took place and no well-developed eggs were found in 
the females before the fall rains began. On the uplands of Kansas, egg 
deposition by M. different ialis began about October 19 . At this time 
along the Missouri River bottom in eastern Nebraska and western Iowa, 
where green food was more abundant, oviposition by this species was 
completed. 
The heat and drought, no doubt, destroyed many of the adults. 
Observers report that the hoppers were so inactive during the extreme 
heat that it was possible to walk up and pick them off the fence posts 
and shrubs without disturbing them. 0. A. Bieberdorf, in Oklahoma, 
reported a heavy mortality among M. diffe rent ialis under such conditions, 
Workers in other States reported the same thing, these reports being 
corroborated by farmers and county agents. In these areas it is very 
probable that many female adults died without depositing eggs. 
The map for the fall survey for 193^ shown the relative distri- 
bution of the infestations expected in 1937. This is basod on the 
combined adult-and-egg survey conducted by the Bureau of Entomology 
and Plant Quarantine, in cooperation with State agencies. Infestations 
are most severe in Illinois, Missouri, Iowa, Nebraska, Kansas, North 
Dakota, Montana, Wyoming aad Colorado, and les3 severe in Michigan, 
Wisconsin, South Dak^ten, and 0>lah.oma. 
