38 ANNUAL BEPORTS OF DEPARTMENT OF AGRICULTURE, 19 53 
vide approximately 75 percent of the accessary funds. In this con- 
Dection, we most certainly would not have had the measure of success 
we achieved without the assistance of your Bureau and staff." 
Two sprays on marginal areas may give adequate grasshopper 
control in wheat 
Twenty square miles of farmland in western Kansas were used in 
an experiment to determine means of protecting newly sprouted fall- 
seeded wheat from the second generation of the lesser migratory 
grasshopper. 
From May 24 to 31, 1952, 285 acres of infestation, of first-generation 
grasshoppers numbering 25 to 500 per square yard were sprayed with 
aldrin at the rate of 2.5 ounces per acre, with a ground sprayer. Tin 1 
sprayed area comprised the margins of the wheat fields. As a result, 
populations were reduced to less than 1 per square yard. The residual 
action of the spray lasted 1 month and killed many adults which had 
moved into the treated margins from field infestation- missed by the 
sprayer. A second treatment was necessary. On duly 2, 250 acres of 
margins were .-prayed by plane with aldrin at the rate of 4 ounces per 
acre. Populations which numbered 10 to 20 per square yard were 
reduced to 1 to 3 per square yard. Two sprayings to wipe out the 
first-generation infestation may well be the way to control grass- 
hoppers in the winter-wdieat areas of western Kansas. 
(Grasshopper diseases identified 
With the assistance of personnel doing research on insect diseases 
at the University of California and in Science Service, Canada Depart- 
ment of Agriculture, several diseases of grasshoppers were identified. 
The fungus Empusa qrylli is at present the most widespread and 
destructive disease in Montana. It has been found infecting grass- 
hoppers as early as the second instar. Another disease, No8i ma -p.. 
was found for the first time under field conditions in northern 
Montana. In 1950 this disease was cultured from grasshoppers col- 
lated in the vicinity of the Bozeman, Mont., laboratory. So far as 
known these are the only records of Nosema in grasshoppers. A 
protozoan disease Malemoa loemtae has infected grasshoppers under 
Laboratory condit ions. 
(Good initial grasshopper hills obtained with several insecticides 
Emulsions and solutions of aldrin were about equally effective 
for grasshopper control in field tests OD l 1 r acre plots of alfalfa at 
Tempe. Ariz. I tosages of I _,. l. 2, and I ounces of aldrin and j L . and 2 
ounce- of dieldriE per acre were used. These insect icides were -lightly 
more effective in Bnort, than in tall, dense alfalfa. They gave about 
equal control in green and dvy alfal ca. Kill from contact act ion alone 
was 60 percent as high, and from ingestion 7."> percent as high, as 
from contact and ingestion combined. Tin 1 peak grasshopper reduc- 
tion was usually reached within 3 day-, but with dieldrin or the higher 
of aldnn there was ><>me residual effect for lo days or longer. 
II sptachlor at either 2 or 3 ounces per acre was effective in con- 
trolling grasshoppers in alfalfa under conditions which prevailed 
early in L952 in A ri/ona. I n Seven replicated tests of emulsion sprays 
tin- insecticide at 2 ounces per acre gave an average kill of 92 percent. 
At ."> ounces per acre the kill was 96 percent. KI'X nt C) ounces per 
acre gave an average kill of 90 percent J at '2 ounces Only 61 percent. 
