436 



FRUIT INSECTS 



Mea7is of control. 



The grape-berry moth can be fought most efficiently by 



thorough spraying with arsenate of lead, 6 pounds in 100 gallons 



of water or Bordeaux mix- 

 ture. The first application 

 should be made shortly after 

 the fruit sets; the second 

 about ten days later and the 

 third about the middle of 

 July in New York, just as 

 the eggs of the second brood 

 are hatching. In cases of 

 severe infestation it is some- 

 times necessary to make an- 

 other application about ten 

 days later. The caterpillars 

 of the first brood do not en- 

 ter the grape-berries, but feed 

 on the outside, thus offering 

 a better opportunity for poi- 

 soning them than is the case 

 with the second brood. Fur- 

 thermore, they are compara- 

 tively few in numbers and 

 each one destroyed early in 

 the season means many less 

 caterpillars in the succeeding 

 broods; hence the import- 

 ance of thorough spraying 

 for this brood. Thorough 

 and careful work with a 



sprayer giving high pressure are necessary to throw the spray 



into the grape clusters, where the newly hatched caterpillars 



will get the poison in their first meal. 



Fig. 376. — Cluster of grapes injured by 

 the grape-berry moth-caterpillars. 



