THE GRAPE-BERRY MOTH. 



53 



The sections were laid off in seven plats of approximately 1 acre 

 each. There were five rows of vines in each plat. (See plan of plat 

 arrangement, fig. 18; dotted lines in figure indicate divisions of plats.) 



The insecticides in all cases were applied with Bordeaux mixture 

 since it is desirable to use this fungicide at the time the applications 



Fig. 17.— Vineyard in which poison-spray experiments were conducted against larvae of the grape-berry 

 moth during the seasons of 1907, 1908, and 1909; vineyard of Mr. W. S. Wheeler, North East, Pa. (Original.) 



are made against the larvae of the grape-berry moth, to control 

 fungous diseases, such as black rot and mildew. In all cases where 

 arsenate of lead was used the Bordeaux formula was 5 pounds of lime 

 and 5 pounds of copper sulphate to 50 gallons of water. Where 

 arsenite of lime was used with the Bordeaux an additional pound of 

 lime was used to counteract any free arsenic which might be present. 



I 

 I: 



id. 

 --_ 



3ZE: 



Fig. 18.— Plat arrangement of poison-spraying experiments against the larvae of the grape-berry moth in 

 the vineyard of Mr. W. S. Wheeler, North East, Pa., 1907. (Original.) 



A gasoline-engine vineyard sprayer outfit (fig. 19) was used for 

 making the application. 



The spray was applied to the vines from the machine by means of 

 a fixed-nozzle arrangement (see fig. 19). To a vertical rod on both 

 sides of the back end of the machine two short spurs of |-inch pips are 

 attached. Each spur carries a large nozzle of the cyclone type from 

 which the spray is discharged into the side of the vine on the trellis. 



