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grasshoppers appeared near Wall Canyon, 1 l/ 2 miles south of the H, tt 
ranch. It is assumed that heavy egg deposition took place in this area, for 
in the spring of 1939 grasshopper nymphs were first observed here, and 
from all indications the infestations for 1939 arose from egg beds laid 
down in the vicinity of Wall Canyon, The flight that appeared at the Turner 
ranch in all probability was the same one that settled near W^*l Canyon, as 
the two areas are only 8 to 9 miles apart. Information and observations 
made led the writer to believe that only one band of grasshoppers was pre- 
sent in Big Smoky Valley in 1938, Eggs are reported to have habched during 
the second and third weeks in March, the spring of 1939 being an early one. 
The nymphs were ve:'y active and it was reported tha.t they began to migrate 
during the early i:. -.stars. Adult grasshoppers were observed on May 13 
(10 percent of pop u'ation) and on May 21 from 95 to 98 percent of the known 
populations were winged. Mating was reported on May 20, and egg laying 
observed to be taking place on June 1, Egg laying observed on June 1, was 
only a very small percentage of the local population. Egg laying was well 
under v/ay by June 21, Egg deposition continued until the latter part of 
July, at which time very few surviving adults were fo^and, natural mortality 
having reduced populations to this degree, 
"The 1939 infestation spread from an area 2 by 3 miles in size on 
the low hills and knolls between Pablo and Wall Canyons to a total area 
of 90 by 15 miles. This latter area extended from Willow Springs mainten- 
ance station, Eye County, in the south, to 20 miles north of Route 50 in 
Lander County, In the 1939 fall egg survey there were 11 areas having a 
combined acreage of egg beds of 19,000 acres. Egg laying began around 
June 1 and continued until late in July, Most of the oviposition took 
place between 9 a,m, and 12 noon. Egg beds were fairly well defined and in 
most cases q.uite concentrated. The number of pods found per square foot 
ranged from less than 1 to 285, A distinct preference for gravelly and 
rocky soil was shown in that all egg beds were in this type of soil. The 
tops of knolls, low hills, alluvial fans at canyon mouths and sides of can- 
yons were the topographic sites chosen for egg deposition; spots without 
southern or western exposuresof good drainage features were avoided for 
egg deposition,” 
Predators and Parasites in Relation to the 1939 Outbreak 
During the egg survey in the spring of 1939 estimates were made 
of the damage done to eggs by egg predators and parasites. The average 
reduction of good eggs by predators amounted to 35 percent in eastern 
Wyoming and western Nebraska and South Dakota, Bee-fly larvae were the prin- 
cipal predators, with blister beetles second and carabids a minor third. 
In eastern Montana and western North Dakota the egg reduction amounted 
to 20 to 75 percent and was due mainly to the work of bee flies. 
In southeastern South Dakota, northeastern Nebraska, and western 
Iowa, blister-beetle larvae were more important than the bee fly. In 
places of greatest egg reduction, carabid larvae outnumbered the blister 
beetle from 2 to 8 times. Mites. Trombidium sp,, were also found throughout this 
