40 BULLETIN 550, U. S. DEPARTMENT OF AGEICULTUEE. 



will not control it. When spraying can be employed these measures 

 are unnecessary. 



A number of other measures reduce infestation and generally may 

 be employed as a part of vineyard practice without additional 

 expense. When commercial vineyards are infested, the worst areas 

 should be harvested as early as possible and the "trimmings" re- 

 moved, to secure the largest weight for the crop and to remove as 

 many larvae as possible from the vineyard. Clearing away brush 

 in the neighborhood of a vineyard will destroy the protection for 

 hibernating pupae with an ultimate reduction in infestation. When 

 it is in keeping with cultural practice, pupae hibernating under the 

 vines should be covered with earth in the spring by plowing, and this 

 covering should remain until the period of blossoming of the grapes, 

 when it should be removed with a horse hoe. This plowing should 

 not be allowed to interfere with spraying. 



These practices, it must be remembered, while reducing infesta- 

 tion, will not control it, and they should not be expected in any way 

 to take the place of spraying. 



The following spraying practice has been found most satisfactory: 



The spray mixture — 

 Arsenate of lead — 



Paste . pounds. . 3 



Or powder do Ih 



Resin fish-oil soap do 1 



Bordeaux mixture — 



Copper sulphate do 3 



Lime do 3 



Water gallons. . 50 



Method of application, with "trailers": 

 Spray schedule — 



First application, immediately after falling of grape blossoms. 

 Second application, when grape berries are just touching (or about two weeks 

 later). 



Under some conditions it may be desirable to modify the spraying 

 practice outlined above. 



In case of extremely heavy infestation the amount of arsenate of 

 lead should be increased to 5 pounds (paste) or 2\ pounds (powder), 

 at least in the last application. 



If resin fish-oil soap is not available a laundry soap containing 

 resin may be substituted in its place. Laundry soaps, however, vary 

 greatly in their sticking and spreading qualities, and great care 

 should be used in selecting those best suited to this purpose. What- 

 ever soap is used, care must be taken to have it thoroughly dissolved 

 before adding it to the spray mixture to prevent clogging of the 

 spraying machinery. 



The use of Bordeaux mixture, while not having a direct effect upon 

 the berry moth, is recommended, to prevent burning of the grape 



