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SPECIAI REVIEWS 
EUROPEAN CORIJ BORER 
The fall survey in New England was completed about the middle 
of November. This work included a comparative survey of the known in- 
fested territory and a survey to determine new infestation bordering 
on the known infested area. The single- gene rat ion infestation is 
spreading from Uew York eastward into New England while the t<*o- genera- 
tion infestation in IJew England shows a normal fluctuation. 
Perhaps the most outstanding development in the corn-borer work 
during the past; season was the $10,000,000 corn-borer clean-up experiment. 
The two main objects of this campaign were to lesions trate (l) whether 
it was possible to retard further spread of the pest by a thorough farm 
clean-up of corn, stalks, etc., over the western and southern area 
then known to be infested with the borer and, (2) whether such a clean- 
up would result in the prevention of increase and, possibly, in the 
actual reduction of the number of borers in infested territory for the 
following year and thus demonstrate the practicability of control as a 
continuing farm practice. 
The results of the 1927 campaign indicate that: 
(l) It is improbable, under existing conditions goyexning State, 
cooperati on in such effort; that the natural spread of the borer to new 
territory can be retarded materially, although it is appreciated that the 
volume of such spread may be reduced n oy the thorough clean-up of the en- 
tire infested area, inclusive of the border counties and townships. Be- 
cause of the inability of some States to include in the clean-up campaign 
the lightly infested border area, the normal spread of the pest 
in such areas occurred in 1927. 
A total of 794 townships were added in 1927 to the area previously 
quarantined on account of the corn borer. The spread discovered in 1927 
is shown roughly on the accompanying map. 
(2) It is possible to keep dow n the number , of borers and to prevent 
serious commercial damage to corn_by_a.. thorough c one erted . clea n-up^ in 
infested territory. The infestation survey following the lb27 spring 
control campaign showed that the number of borers per 100 stalks in both 
Ohio and ITew York, representing two-thirds of bhe townships in the con- 
trol area .had been reduced. The reduction in Onio was from oorers per 
TOO stalks in 1926 to 5 borers per 100 stalks in 1227. The reduction 
in Hew York was from 12 borers per 100 stalks in 1926 to 10 borers per 
100 stalks in 1927. In Michigan, however, o-ing to the existence of con- 
ditions decidedly favorable to the borer increase, particularly, as 
regards reinf estation from Canada, there was an increase in the number 
of borers. Pennsylvania also showed an increase. The increase in Michigan 
was from 12 borers per 100 stalks in 1926 to 27 borers per 100 stalks 
in 1927. In Pennsylvania the number increased iron 7 borers per 100 
