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Illinois; Harford in Maryland; Brown in Ohio; Essex, Isle of Wight, James City, 
and Hew Kent in Virginia; and Columbia, Portage, Walworth, and Waushara in 
Wisconsin. 
The Bureau of Entomology and Plant Quarantine and the interested States 
coopera ted again in the fall of 1940 in a survey to determine the relative 
abundance of the borer over a considerable portion of the infested territory. 
Significant increases in abundance in 1940 from 1939 occurred in comparable 
surveyed sections of Indiana, Ohio, western Hew York, Long Island, H. Y., Hew 
Jersey, Delaware, Maryland, and Virginia; significant decreases in Vermont, 
Massachusetts, Connecticut, and Rhode Island; and no significant changes in 
the levels of population in Wisconsin, Michigan, Bucks County in Pennsylvania, 
eastern Hew York proper, Hew Hampshire, and Maine. Infestation in the few 
.counties surveyed in southeastern Wisconsin in 1940 was light, as in 1939 » 
whereas in southeastern Michigan larval populations continued at high levels. 
Population levels in Illinois were very low. The increases in abundance of th 
insect from 1939 to 1940 in the surveyed portions of Indiana and Ohio brought 
the populations in these States to the highest levels on record, and in the 4 
counties surveyed along the southern edge of Lake Ontario in western Hew York, 
the borer reached its maximum abundance for that section of the country. Al- 
though less abundant throughout Hew England and in eastern Hew York proper in 
1940 than in 1939 » the corn borer was much more numerous southward along the 
Atlantic coast from Long Island through Hew Jersey, Delaware, Maryland, and 
■Virginia. The highest infestations per county in 1940 occurred in Hassau 
County, Long Island, H. Y. , and Hiagara County, H, Y*, which averaged 742.2 
and 709.6 borers per 100 plants, respectively. Other relatively high popula- 
tions — 501 to 700 borers per 100 plants — were found in the counties of Gratiot 
and Sanilac, Mich.; Columbia and Orleans, H, Y.; Fairfield, Conn,; Burlington, 
H. J.; and Accomac and Princess Anne, Va. Some of the highest populations of 
the European corn borer known in the United States were observed in Princess 
Anne County on the mainland of Virginia where the average number of borers per 
100 plants determined by the survey was 601.2. Individual corn plants in some 
fields in this county contained more than 100 corn borer larvae. 
In general, infestations in early market sweet corn were much lower in 
1940 than in 1939 > averaging about 5 borers per plant in the most heavily in- 
fested fields in truck-crop sections in Hew Haven County, Conn.; Burlington 
County, H, J.; Albany and Columbia Counties, in the Hudson River Valley, H. Y, : 
and Luce„s County, Ohio, The 3 fields observed in Burlington County, H. J., 
with the highest infestations averaged l6, l4, and 13 borers per plant, respec- 
tively. The average of 28 borers per 100 plants observed in early market 
sweet corn in Maine was lower in 1940 than in comparable counties surveyed in 
1939. A detailed account of the corn borer, together with a map, was published 
as Supplement to Ho. 9 of the Insect Pest Survey Bulletin, December 20, 1940. 
(C. M, Packard, Bureau of Entomology and Plant Quarantine, U. S. D. A.) 
CHINCH BUG 
The seasonal development of the chinch bug during 1940 roughly paralleled 
that of the two previous years, in most of the infested area. Hibernation 
surveys made late in the fall of 1939 and early in the spring of 1940 showed 
