INSECT PEST SUP. V E Y BULLETIN 
Voi. 19 
Supplement to Number 9 December 15, 1939 
STATUS OE THE EUROPEAN CORN BORER IN 1939 
A. M. Vance, Entomologist 
Bureau of Entomology and Plant Quarantine 
United States Department of Agriculture — / 
Distribution 
The territory in northeastern United States known to be infested by the 
European corn borer ( Pyraus ta nubilalis Hbn# ) was extended in 1939 to include 
Cook, DuPage, Kankakee, Lake, and W ill Counties in Illinois; Camden, Currituck, 
and Pasquotank Counties in North Carolina; Kent and New Castle Counties in 
Delaware; Chester, Dele, wore, Lancaster, and Montgomery Counties in Pennsylvania; 
Dodge, Green Lake, Jefferson, Oconto, Outagamie, Shawano, and Waupaca Counties 
in Wisconsin; and Lancaster, Nansenond, and Richmond Counties in Virginia. 
Pali Abundance 
An extensive survey to determine the relative abundance of the European 
corn borer in com over the greater part of the territory infested by the insect 
was conducted in the fall of 1939 Uy the Bureau of Entomology and Plant Quaran- 
tine in cooperation with interested -States. The survey procedure utilized by 
the Bureau in 1939 was somewhat modified from that of previous years, the change 
resulting in an increase in the size of the area that could be examined without 
i / 
The information presented in this report was assembled at Toledo, Ohio, 
as a phase of European corn borer research, with W, A. Baker in charge. All 
data on abundance of the corn borer in the fall of 1939 in Indiana (35 counties), 
Maine (13 counties), and New Jersey (19 counties) were collected by the State 
Conservation Department of Indiana and the State Departments of Agriculture of 
Maine and New Jersey, respectively. The Agricultural Experiment Station at 
Geneva, N, Y, , surveyed 10 counties in eastern Now York, the Vermont Department 
of Agriculture surveyed 10 counties in the northern half of Vermont, and the 
New Hampshire Agricultural Experiment Station surveyed 5 counties in eastern 
New Hampshire, Some assistance in the field work was also given by the agric- 
ultural experiment stations of Delaware, Maryland, 'and Massachusetts in their 
respective States, Eirst records of the European corn borer in Illinois were 
.contributed by the Natural History Survey and State Department of Agriculture 
of Illinois, and in North Caroliria by the State Department of Agriculture, and 
new county records of the insect within States already infested were furnished 
by the State Deportments of Agriculture of Pennsylvania, Virginia, and Wisconsin, 
The Bureau of Entomology and Plant Quarantine is appreciative of the interest 
and coopera.tion of all States in which the survey war conducted or from which 
records of distribution were obtaine d in 1939 . 
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