GRAPE-BERRY MOTH IN NORTHERN OHIO. 
9 
The blooming period of grapes from June 21 to July 1 begins with 
the bloom of the Ives variety, one of the varieties grown commercially 
in the northern Ohio sections, and ends with the falling of bloom from 
the Catawba variety, also a commercial variety of importance in the 
sections studied. It is seen that less than 5 per cent of the total 
emergence occurred before the beginning of bloom, 50 per cent in the 
10-day period during bloom, 25 per cent in the next 10-day period, 
and 21 per cent during the remainder of the season. 
*> < j j- 
Fig. 2. — Diagram showing the time of emergence of spring-brood and first-brood moths of the grane- 
berry moth at Sandusky, Ohio, 1917. 
A rather close correlation is evident between the rate of emergence 
and the daily mean temperatures. 
PROPORTION OF SEXES OF SPRING-BROOD MOTHS. 
Table XI. — Proportion of sexes of spring moths of the grape-berry moth, Sandusky, 
Ohio, 1917. 
Sex of moths. 
Number 
of 
moths. 
Per cent 
of 
sexes. 
305 
1,116 
43 
21 46 
Female 
78. 54 
Total 
1,464 
100. 00 
The high percentage of female moths, as shown in Table XI, seems 
to account for the frequent heavy infestation by second-brood larvae 
after a comparatively light first-brood infestation. 
7678°— 20- 
