196 THE APPLE 



Insects affecting the Fruit 



Codling moth (Cydia pomonella, L.). Of the insects preying 

 directly upon the fruit of the apple the codling moth, or apple 

 worm, is the most important economically. Because of its universal 

 distribution it is well known both to producer and to consumer. 

 To the latter, only the result of the insect's injury is familiar, the 

 worm itself usually having long since forsaken the apple. When 

 one encounters an apple tunneled by cavities with blackened and 

 bitter walls, and partially filled with the blackish frass, or castings, 

 of the worm, he may know that the agent of these hidden and 

 distasteful mining operations is the larva of the codling moth. 



Fig. 84. Codling-moth adults. (Department of Entomology, Cornell University) 



But it is to the grower that the insect is best known and most 

 unwelcome. To him the moth represents steadily cumulative losses 

 throughout the whole growing season. A large percentage of the 

 apples which fall prematurely from May until harvest time are vic- 

 tims of the voracity of the codling-moth larva. One has but to 

 keep a record of the windfalls from a single unsprayed tree for a 

 season, classifying them according to the initial cause of their fall, 

 to realize that the apple worm is a guest with an appetite that is 

 costly to satisfy. Nor does its havoc stop here. Not only does it 

 cut off many apples from all possibility of maturity but it so affects 

 others that cling to the tree that they are, at best, unfit for sale 

 except as culls. 



History of the codling moth. In order successfully to combat 

 an insect, it is necessary to know its history, for most insects are 



