66 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



plowing under the pupa-infested leaves in this manner will destroy 

 the insect in this stage, but it is highly probable that many fatalities 

 will result from the method. It is believed that greater success will 

 result from an endeavor to destroy the pupa 3 which are in cocoons 

 upon leaves that remain in the vineyard throughout the winter than 

 in the destruction of leaves outside of the vineyard which are blown 

 into fence rows, ditches, and adjacent rough lands. No moths of this 

 insect have been reared from grape leaves gathered from these latter 

 locations, although several attempts have been made to secure speci- 

 mens from them. 



Fig. 22.— Overwintering cocoons of the grape-berry moth upon leaf on ground, beneath a badly infested 



grapevine. (Original.) 



CONCLUSION. 



Wherever vineyards have become badly infested by the grape-berry 

 moth serious injury to the crop has resulted and the owners of the 

 infested vineyards have found it a very difficult pest to eradicate. 

 Many vineyardists who have tried to control the pest with a poison 

 spray have not met with as complete success as they would wish. 

 Many such instances of complete or partial failure have been observed. 

 In nearly all of these cases, however, investigation has shown that 

 this lack of success, in all probability, was largely due, either to 

 inferior spraying equipment which failed to deliver the spray in 

 sufficient quantity and force to thoroughly cover the clusters, or to the 

 fact that the applications were not made at a time when the majority 

 of the larvae were about to hatch. Frequently both of these condi- 



