DUSTING AND SPRAYING CURCULIO AFTER BARVEST. 
Table 6 shows that all but one of the 90 beetles collected from 
plat 1, which received two application- of dust, died before September 
24, when the work was closed; 3] of the 90 collected from plat 2, 
which received one application of dust, were alive on September 24; 
of the 90 beetles collected from plat 3, which received no treatment, 
only 5 had died by the time the work was closed. One of these was 
killed by a spider and one by a fungus, leaving only 3 that died from 
unknown causes. 
The dust apparently loses its effectiveness on the trees after about 
two week-. In that time it perhaps is either blown off or washed off, 
or has become so diluted as to be ineffective. This view is confirmed 
by the fact that most of the beetles from plat 2 remaining alive in 
jars on September 24, when the work was closed, were collected after 
the dust had been applied two weeks. On plat 1, where the second 
application was made 12 days after the first, the dust was nearly 
100 per cent effective in killing the confined eurculios. 
Table 7 gives the percentages of eurculios remaining alive on Sej 
tember 24. when all jars were closed. 
Table 7.—Percetita ■ dios cdivt at cl ervment, 1921. 
PLAT 1. DUSTED TWICE. 
N umbei 
Date col- 
lected. 
Number Septem- 
ber 24. 
Per cent Septem- 
ber 24. 
Alive. Dead. 
Alive. 
Dead. 
10 
Aug. 15 
Aug. 17 
Aug. 19 
Aug. 22 
Aug. 24 
Aug. 27 
Aug. 30 
Sept. 1 
Sept. 3 
Nv m her . Xu mber . 
10 
Per cent. 








10 
Per cent. 
100 
10. .. . 





? 
10 
10 
10 
10 
10 
10 
10 
9 
100 
10 
100 
10 
100 
10 
100 
10. .. 
100 
1(1 
100 
10 
100 
10 
90 
PLAT 
DUSTED ONCE. 
10 
1" 
10 
1" 
10 
10 
10 
16 
10 
Aug. 15 

10 

Aug. 16 

10 

Aug. 18 

10 

Aug. 20 

10 

Aug. 23 
4 
6 
40 
Aug. 26 

o 
50 
Aug. 29 
10 

100 
Aug. 31 
3 
7 
30 
Sept. 3 
9 
1 
90 
100 
100 
100 
100 
60 
50 

70 
in 
PLAT 3. NO TREATMENT. 
10 
10 
10 
10 
10 
10 
10 
10 
10 
Aug. 15 
9 
1 
90 
Aug. 16 
10 

100 
Aug. 18 
6 
4 
60 
Aug. 20 
in 

100 
Aug. 23 
10 

too 
Aug. 26 
10 

100 
Aug. 29 
111 

100 
Aug. 31 
10 
100 
Sept. 2 
10 
100 
-24— Bull. L2(K 
