Boll weevil population counts were made just before each application and 
1, 5, and 10 days after each application in several fields with high weevil 
populations, Ground-trash population records were made biweekly during the 
period and on November 29 after weevils had left the fields to hibernate, 
As shown in table 9, 60 percent of the population consisted of diapausing 
populations 2); hours after applications. This compared with )2 percent before 
applications were begun and 32 and 3); percent 5 and 10 days after applications. 
The diapause percentage was almost constant on comparable dates in the untreated 
area. These results show that methyl parathion applications at 10-day inter- 
vals reduced the percentage of boll weevils in diapause to some extent, but 
a shorter interval would be necessary to obtain a good reduction or elimination 
of diapausing boll weevils. 
Table 9.—Boll weevils per acre and diapause determinations in 8 fall-treated 
and 5 untreated fields in Quebec area, Tallulah, La., 1961 
Treated Untreated 
Date Date Total Total 
treated inspected population | In diapause population | In diapause 
Percent 
Sept. 28-- 
Oct, 10--- 
18--- 
Sept. s20nm 
Oct lOza = 
Sept. 207— 
Oct O=== 
18--- 
Average q—- 
Not included in average. 
x) 3 fields sampled. 
3/ fields sampled. 
4/ 1 field sampled. 

Populations were reduced 88, 83, and 67 percent 1 day after applications 
were made on September 28 October 10). and 18, as shown in table 10. Diapause 
populations were reduced 83, 625 and hé percent, respectively. Low temperatures 
by October 18 probably reduced the effectiveness of methyl parathion on that 
date. 
Baie 
