70 DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



CONTROL. 



As many of the larvae eat their way through the fleshy hull cover- 

 ing of the walnut, it is probable that a thorough spraying with 

 arsenate of lead in the month of August would greatly reduce the 

 infestation. This treatment would apparently be as effective in 

 destroying larvse from eggs placed promiscuously over the foliage 

 and nuts as in the case of the apple. From the fact that many of 

 the larvse gain entrance to the walnut after the hull has parted at 

 the tip, the poison would, of course, not be effective against these. 

 The infestation can. no doubt, be greatly reduced by maintaining 

 the packing shed and drying grounds some distance from the walnut 

 grove. 



It is the practice of many pear growers to save all windfalls in 

 the orchard and culls from the packing shed. These pears are either 

 stored in large trays, stacked in the shade, or else the pears are 

 covered with straw in layers on the ground. As a rule, the culls 

 from the packing ground are nearly all infested with immature 

 larvae of the codling moth, which reach their full development and 

 produce moths during the ripening period of the walnuts. This, 

 in most cases, is the source of infestation of walnut groves found 

 to be most seriously troubled with the codling moth. 



