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EUROFSAN COM BORER 
"The spread of the European corn "borer ( Py r au a t a nub ilalis Hbn . ) 
during 1930 was retarded "by the drought. To the westward, the insect was 
discovered in a single new township of each of the following Indiana, 
counties: Delaware, Fayette, Fulton, Hamilton, Porter, Pulaski, and Rush; 
it was also found in nine townships of Madison and Henry Counties. In 
Ohio it nearly or quite reached the Ohio River in Adama, • Clermont, Gallia, 
and Meigs Counties and was found in new townships in Highland, Pike, and 
Jackson Counties. It also crossed the Ohio River into three districts of 
Lewis .and Bracken Counties, Ky. New infestations were discovered in six 
townships in Mason, Wood, Ritchie, and Tyler Counties, W. Va.; in eleven 
townships in Lehigh and Northampton Counties, Pa.; and in eight townships 
in Warren, Hunterdon, and Essex Counties, N. J. The one-generation strain 
spread eastward in the northwestern part of Litchfield County, Conn., and 
the two-generation strain spread westward in Connecticut in Tolland, 
Hartford, and New Haven Counties, as well as extending along Long Island 
Sound into Fairfield County, The only infestations found outside of the 
States now under quarantine were these in Kentucky, along the Ohio River. 
It is believed that these out "breaks arose through spread by the river. 
The degree of infestation in the 1930 corn crop as compared to that of 
previous years, according to this year's survey, shows that there has "been 
an average reduction in corn-borer abundance of approximately 25 per cent 
as compared to 1929. Decreases of approximately 21, 58, and 29 per cent 
were indicated for Michigan, Ohio, and Pennsylvania, respectively, and 
increases of approximately 33 and 11 per cent were indicated fcr Indiana 
and New York, respectively. These differences were brought about by vari- 
ations. in the drought conditions. The larval survival in 1930 on the corn 
at the European corn borer demonstration farm at Toledo was reduced to 4 
per cent as compared to 25 per cent on the same variety of corn in 1929. 
The reduction appears to be due largely to the extremely hot, dry spring 
and summer, the heat being so intense as to prevent a considerable percent- 
age of the eggs from hatching in many areas and causing the death of a 
large number of young larvae. In the two-generation area in New England, 
comprising Maine, New Hampshire, eastern Massachusetts, Rhode Island, and 
Connecticut, there has been a general decrease in infestation, although 
an increase occurred in a part of the area. In eastern Massachusetts 
Bristol, Middlesex, and Norfolk Counties show an increase, while Plymouth, 
Dukes, and Nantucket Counties show considerable decrease. In Rhode Island 
there is also a great decrease in infestation, which is largely due to good 
clean-up measures during the winter nonths, and unfavorable conditions for 
the first generation. Commercial damage to some extent in corn' was observed 
• . : in some of the counties in southern Massachusetts and Rhode Island, espe- 
cially by the second generation. The commercial damage in the one-gener- 
ation area in the Great Lakes section was very slight. 
"Below is shown the status of infestation, by States, in 1929 and in 
1930, in terns of the average number of borers per 100 plants. 
