INSECT PEST S U H IE Y BULLETIN 
Vol. 19 
Supplement to Number 7 
September 15 , 1939 
HESSIAN ELY SURVEY AT HARVEST TIME 1939 
Summarized by W. B. Cartwright 
U. S. Bureau of Entomology & Plant Quarantine 
Division of Cereal and Eorrge Insect Investigations 
Eield surveys made by the Bureau of Entomology and Plant Quarantine at 
Manhattan, Kans.; Lafayette, Ind.; - and Carlisle, Pa,, and by the State agricultural 
experiment stations of Illinois and Ohio indicate that hessian fly infestations 
are low in wheatfields throughout Maryland, Delaware, Virginia, north-central 
North Carolina, Tennessee, southern Illinois, and central and western Kansas* 
There are, however, menading populations of flies in local fields and areas in 
most of these States or districts, 
Hessian fly infestations range from low to moderate in eastern and south- 
central Pennsylvania, Kentucky, southern Indiana, southern Michigan, southwestern 
Missouri, and eastern Kansas, with local infestations trending upward. No sur- 
veys were reported for the remainder of Missouri or for Iowa or Nebraska, but 
fragmentary data indicate that infestations are from low to moderate in central 
and northern Missouri, southeastern Nebraska, and southern Iowa. Observance of 
the safe-seeding dates is advised in all areas of low-to-moderate infestation, 
because the season has been favorable for hessian fly and for growths of volunteei 
wheat in many areas . 
Prom moderat e- 1 o- heavy infestations of the hessian fly occur in north- 
central and western Pennsylvania, north-central Ohio, the northern two-thirds of 
Indiana, and central Illinois, In these areas the fly is menacing and the seeding 
of wheat should be delayed until the safe-seeding date or from 1 to 3 hays after 
that date, in order to lessen the chances of heavy infestation of hessian fly* 
The summarized data below and the accompanying map indicate more fully the 
regions covered by the survey and the general trend of fly infestations. A 
field sample in the survey usually consisted of 50 wheat stems. 
