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vestern Pennsylvania in 194Q the infestation was very light, no borers being 
found, in half of them and less than 17 larvae per" 100 pl'ants in each of the 
other 15, In Centre County, in the center of the State, there was an average 
of 112.8 borers per 100 plants in 1940, and. in Bucks County the average of 117 
"borers per 100 plants in 1940 had about, the same significance as that of 142 
found there in 1939* Corn borer surveys in 1939 and 1940 together covered all 
of Pennsylvania except a section of 10 counties in the . southeastern part of the 
State, not yet known to bo infested, and 4 neighboring counties first found in- 
fested in 1939. Sizable infestations in the 1939 and 1940 surveys in Pennsyl- 
vania were found only in Centre and Bucks Counties. 
West Virginia . — Measurable populations of the corn bbrer were not found in 
any of the 10 infested counties in the northwestern corner of West Virginia, 
surveyed for the first time in 1940. ‘ ■ 
New York . — The corn borer was much more abundant in 1940 than in 1939 i n 
the counties of Niagara, Orleans, Monroe, and Wayne,. all located along the 
southern shore of Lake Ontario" in western New York. There' populations of the 
insect were higher in 1940 than in any other year on record, the average number 
of borers per 100 plants in this group of 4 counties having" increased from 101 
in 1939 to 510*2 in 1940. In Niagara County the borer populations per 100 
plants averaged 709*6* On Long Island (Nassau and Suffolk Counties) there was 
also' an increase in abundance of the borer — from 221.5 larvae per 100 plants in 
1939 to 493 in 1940 — being most pronounced at the western end of the island, in 
Nassau County, which had the maximum infestation in the country in 1940 of 
742.2 borers per 100 plants, as an average for the entire county. Taken as a 
whole, the 9 counties surveyed in the Hudson Paver Valley, in eastern New York, 
in both 1939. and 1940 showed little change in these 2 years. An infestation of 
3,850 borers per 100 plants in 1 cornfield in Columbia County in 1940 raised 
considerably the year’s average for that county, • Greene County also tended to 
have more borers in 1940 than in 1939* Lower, populations were found in Albany 
Coun'ty in 1940 than, in 1939 and a trend toward decrease from 1939 "to 1940 was 
apparent in Orange, Rensselaer, Saratoga, end Schenectady Counties. 
New England . — In No w England populations, of the European corn borer de- 
clined from 1939 "to 1940, the average for the 6 'States of 228.1 borers per 100 
plants in 1939 dropping to 111. 5 in 1940. The infestation in Maine was light ' 
in 1940, averaging 2,2 borers per 100 plants, as compared with 10.2 in 1939* 
In New Hampshire there, was a downward trend in abundance of the insect, from 
51.4 borers per 100 plant's in 1939 to 34 in 1940, and significant decreases 
from 1939 to 1940 occurred in Vermont, Massachusetts,' Rhode Island, and Connecti- 
cut. In Vermont the" decrease was from 66’. 2 borers per 100 plants to 39*6; in 
Massachusetts from 496.2 to 159*1; in Rhode Island from 664.1 to 264.6; and in 
Connecticut from 471 to 348.4. With the 'exception of Bennington and Windham 
Counties, Vt., Sullivan County, N. H. , and Hampden County, Mass,, county popu- 
lations of the borer exceeding 100 larvae per 100 plant's were confined to the 
States of Conhecticut and Rhode Island and to 6 counties along the coast in 
eastern Massachusetts, Fairfield County in Connecticut had the heaviest in- 
festation, with 539*6 borers per 100 plants, while 3. other Connecticut -'Counties-- 
Middlesex, Hartford, and New Haven— averaged 472.2, 443.4, and 393*4 borers per 
100 plants, respectively. The only other county in New England with an average 
of more than 300 borers per 100 plants was Barnstable, in Massachusetts, with 
334. 
library 
STATE PLANT BOARD 
