April, '12] 



BALL: DRIVING SPRAY 



15X 



Number of Worms. In the last section of the table the average 

 of the five unsprayed checks for each orchard is given. In the first 

 brood the unsprayed checks in the Stillman orchard had an average 

 of 311 worms per tree, or 48 per cent wormy. Taking the average 

 of all counted trees as the average of the orchard and this number of 

 worms per tree would make the average for the orchard 65 per cent. 



The Woodbury orchard had 120 worms per tree in the first brood, 

 or 50 per cent wormy, or, on the average of all trees counted, 37 per 

 cent wormy. 



The Nokes orchard bad 100 worms per unsprayed tree in the first 

 brood, or 16 per cent wormy, or, on a basis of the average of all the 

 counted trees, 14 per cent wormy. 



Counting the second brood as ten times as great as the first, which 

 is conservative for western conditions, we would have had the follow- 

 ing condition in these orchards if there had been no spraying done. 



Instead of this, the check trees were banded and from ^ to f of the 

 first brood worms captured, and of the remainder, we would expect a 

 considerable portion to scatter from the five unsprayed trees to the 

 600 or more sprayed ones surrounding them, and yet these unsprayed 

 trees in the Stillman orchard were 85 per cent wormy and in the AVood- 

 bury orchard practically all wormy (92%). Of the few sound apples 

 remaining some fell early and some few were down underneath the 

 dense foliage of the centers of the trees and thus escaped, while most of 

 the apples on the outside of the trees had three or more worm holes in 

 them. 



In the Nokes orchard, where the first brood was small, only two- 

 thirds of the apples on the unsprayed trees were wormy and only a 

 few had more than one worm. Even after the banding and scattering, 

 we notice an increase of nearly four times between the first and second 

 brood in this orchard. It would of course be impossible to get an 

 increase in the other orchards, as they were half wormy in the first 

 brood. 



It is interesting to note that over four-fifths of the first brood worms 

 went in at the calyx. It is not possible to make similar comparison 



