38 BULLETIN 911, U. S. DEPABTMENT OF AGRICULTUKE. 
Second-brood larvae begin to leave the fruit early in the fall, 
August 22, 1916, August 15, 1918, September 7, 1917, but leave in 
greatest numbers just previous to and during the early part of the 
harvest season. In 1916, 77 per cent of the larvae left the fruit 
previous to the beginning of the Concord harvest and 90 per cent 
previous to the beginning of the Catawba harvest. In 1917 corre- 
sponding figures were 56 per cent and 94 per cent. 
In each brood of moths the females occur in much larger number 
than the males, the proportions being 21 per cent males, 79 per cent 
females in the spring brood, 1917 ; 18 per cent males, 82 per cent females 
in the summer brood, 1917; 25 per cent males, 75 per cent females 
in the spring of 1918; and 21 per cent males and 79 per cent females 
in the summer brood of 1918. A small part of the first-brood larvae 
do not transform to moths the same season but hibernate and emerge 
as moths the following spring. In 1918 this amounted to 5.9 per cent 
of the total number recorded. Of the same lot of larvae but 1.4 per 
cent were parasitized. 
Mating and egg deposition were observed during these investiga- 
tions. The habit of the grape-berry moth larvae of feeding on grape 
leaf galls formed by the grapevine phylloxera was noted. Extreme 
resistance of the larvae to low temperature was also noted, live larvae 
persisting after a minimum temperature of 17° F. had occurred. 
Parasitism was very low and of little consequence as a control during 
these investigations. 
Control measures recommended are cultural methods which will 
leave the overwintering pupae exposed to the elements as much as 
possible. Satisfactory control was effected by two spray applica- 
tions by the " trailer" or hand method of spraying. The first appli- 
cation should be made 3 to 5 days after the young grapes set and the 
second when the grapes first touch in the clusters. 
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