138 JOURNAL OP ECONOMIC ENTOMOLOGY [Vol. 1 



The proportion of apples injured by the first and second brood 

 A^aries with the locality and seemingly according to the percentage 

 which transform to the second brood. Thus, at Durham in 1907, 29% 

 of the wormy apples were injured by the first brood and 71% by the 

 second, and in 1906 about 40% were injured by the first brood and 

 about 60% by the second on unsprayed trees, while at Deerfield, 15 

 miles distant in the hills, in 1907, 70% were injured by the first brood 

 and 30% by the second brood, and at Pittsfield, 30 miles distant, 48% 

 were injured by the first brood and 52% by the second brood on 

 unsprayed trees. 



The effectiveness of the spraying seems to vary somewhat from 

 season to season, and it seems quite possible that if heavy rains fol- 

 low sprays III and IV that their effect upon the larvge feeding upon 

 the foliage would be lessened, whereas the benefit due to spray V 

 would not be so much affected as if it is applied just as the eggs are 

 hatching. Those plots sprayed with only the third spraying show but 

 little total benefit to the second brood, averaging 12%, while those 

 spraj^ed with the third and fifth sprayings show little or no total 

 benefit, due probably to the fact that the destruction of the first brood 

 was so complete that it is very difficult to determine any additional 

 influence, unmistakably due to the effect of the spray on the second 

 brood. But an addition of spray VI (spray VI being applied when 

 the second brood of eggs are laid) gave 70% of the possible benefit due 

 to the direct effect of the spray on the second brood. Spray IV gave 

 a total of 22% of possible benefit, and spray V from 22% to 79% of 

 possible benefit, with an average of 60% of the possible benefit due to 

 the direct effect of the spray on the second brood, this being 22% 

 benefit in terms of the benefit for the whole season, which was but 

 58%, or in other words 37% of the total benefit of the year was due 

 to the direct effect of spray V upon the second brood. 



Analyzing this benefit to the second brood, as to its effect upon the 

 worms entering the calyx and side, we find that in the plot treated 

 with spray III the benefit to the second brood was due entirely to 

 those entering the calyx, giving 46% benefit to the calyx, but showing 

 a loss of 14% or 15% in those entering the side, thus indicating that 

 some of the spray lodged in the calyx affects the second brood which 

 enter the calyx, but that the third spray has no effect on those enter- 

 ing the side, or in other words, kills very few or none of the second 

 brood upon the foliage. When spray V or IV and V are added to 

 spray III, from 75% to 80% benefit to the calyx is secured, but no 

 benefit is secured to the side, but with the addition of spray V and VI 

 (VI being applied for the second brood eggs), 95% benefit to the 



