440 



STATE BOARD OF AGRICULTURE. 



RESULTS. 



It was not possible to include trees of all varieties in the check plots, so the 

 results are given only for varieties which were included in the check plot 

 and bore enough fruit to give some definite idea of the actual results obtained. 

 As the trees in this orchard were young, the number of apples counted was 

 not large. 



TABLE 5. DUSTING APPLES AT TRAVERSE CITY^ 1921. 



Definite counts were not made for Wealthy, but one bushel of fruit from 

 dusted trees and an equal amount from check trees was examined by Mrs. 

 Stickney who reported that in the bushel of dusted apples there were only 

 seven culls, while in the bushel from the check trees there were only eleven 

 which were not culls. 



All apples were classed as "scabby" which showed even a very small 

 scab spot and this of course included many which were not really culls. In 

 the "wormy" grade, all apples showing "stings" were included, although 

 a "sting" is evidence that the poison was effective as a worm must eat before 

 it can be poisoned. 



The control of scab was not uniform with all varieties. This was due, in 

 part, to certain mechanical difficulties with the duster and to irregular air 

 currents before mentioned. These conditions made uniform application 

 impossible. The difference in susceptibility of the varieties also probably 

 affected the results. The differences in the blooming period of the several 

 varieties made it impracticable to apply the dust at the most ideal time for 

 each variety. The Delicious, a late blooming variety, was very scabby as 

 the "pre-pink" and pink applications were not timely for this variety. 



General Statement of Kesults of Apple Dusting Work. 



Scab control. Sulphur dust has continued to give satisfactory control of 

 apple scab. This statement refers to its use in the regular summer schedule, 

 begiiming with the cluster application. The value of sulphur dust when 

 used for the "pre-pink" application has not been fully determined and 

 further work along this line is necessary and is planned for the coming season. 



Copper sulphate dust, in the proportions used, so far has not given satis- 

 factory results on apples. 



Codling moth control. In 1920 when there was about the average amount 

 of codhng moth injury, the dusting method gave satisfactory control but in 



