SPRAYING FOR CURCULIO OX APPLE. 
199 
of late spring frosts, which served to concentrate the injury. Unques- 
tionably a part of the loss shown was due to the apple curculio, which 
was abundant in that locality. At the time of the first application. 
May 16, the petals had just fallen from the trees. The St. Joseph 
results present some points similar to those obtained the same year at 
Mount Jackson, Va., — namely, that when the curculio is excessively 
abundant, satisfactory results ma}' not be obtained by spraying. 
Plat I, winch received 4 applications, shows only 50.10 per cent of 
sound fruit as against 4.05 from the unsprayed trees, representing a 
gain of 46.05 per cent. The single drenching application, given to 
Plat II, resulted in 36.80 per cent of fruit free from curculio. a gain 
over the unsprayed block of 32.75 per cent of the crop. 
Table C. — Results of spraying apples for the plum curculio. St. Joseph. Mo..l'< . 
Plat 
No. 
Treatment. 
Variety. 
Tree 
No. 
Total 
num- 
ber of 
apples. 
Total 
num- 
ber of 
apples 
punc- 
tured. 
Total 
num- 
ber of 
punc- 
tures. 
Per- 
centage 
of sound 
apples. 
Aver- 
age per- 
centage 
of sound 
apples. 
I 
fFour applications Bordeaux mix- 
1 ture (4-4-50) plus 2 pounds ar- 
j senate of lead: May It;, June 9, 
[ July 9, and Aug. 6." 
[One application. Drenched with 
< arsenate of lead, 2 pounds to 50 
I gallons water, May 16. 
>Ben Davis. . 
L..do 
.do 
li 
( ! 
If 
1.747 
1,624 
- 
966 
660 
844 
2.443 
1 . 355 
2.012 
44.7(1 
59. 35 
46 54 
4.950 
2.470 
5,810 
50.10 
II.... 
2.769 
3.019 
1.909 
1.749 
5.0.54 
4.230 
31. 05 
- 
" 788 
3,658 
9.290 
III. 
1,604 
1.437 
1,358 
1,625 
• 
1 . 284 
7.715 
5.275 
4.07 
2 71 
5.44 
1,489 
4.307 
21 . 567 
The records above given in spraying apple orchards for the cur- 
culio are assembled in Table CI, which indicates, in average per- 
centages, the amount of uninjured fruit from each plat from the 
several localities, arranged according to the number of applications 
given. These experiments have extended over a period of several 
years and were made in various places, so that the results are not 
entirely comparable. Even when considering the results of indi- 
vidual experiments, a wide variation is seen in results from orchards 
which received practically the same treatment for example, in the 
two orchards in Virginia sprayed during 1009. 
