INJURIOUS INSECTS 



CODLING MOTH 



Carpocapsa pomonella Linn. 



Plates 1-7 



The work of the last two years with this important pest of 

 the fruit grower has been continued and some extremely inter- 

 esting- data secured. Even one spraying- resulted in obtaining 

 98 to 99 per cent of sound fruit, while the check trees yielded 

 only 67 and 85 per cent of worm-free apples. The second and 

 third poison applications increased the percentage of sound fruit 

 comparatively little. These results confirm those secured in 

 1909 and go far toward showing the possibility of a thorough, 

 timely spraying. The low efficiency of the one application made 

 three weeks after the falling of the blossoms, determined last 

 year as approximately one-half that of a timely application, was 

 confirmed this season by experiments in two orchards under 

 diverse conditions. 



Life history and habits. The discussion of the experimental 

 data may well be preceded by a brief summary of the life his- 

 tory of this species. The codling moth or apple worm, as is 

 well known, winters in a tough, silken cocoon usually found 

 under the rough bark of trees. The appearance of warm 

 weather in the spring, which in New York means late April and 

 early May, is followed by the caterpillars transforming within 

 their silken retreats to the brown, apparently lifeless pupae, and 

 a week or ten days after the blossoms drop, the moths com- 

 mence to emerge and continue to appear throughout the greater 

 part of June. The minute, whitish eggs are deposited largely 

 upon the leaves though a number may be found on the young 

 fruit. These hatch in about a week and as a consequence the 

 young apple worms of the first brood may be entering the small 

 fruit from early in June, approximately three weeks after the 

 blossoms fall, to nearly the end of the month or even later. 

 The caterpillars require about four weeks to complete their 

 growth, at which time they desert the fruit, wander to a shel- 

 tered place, spin a cocoon, transform once more to pupae and 

 in about two weeks, namely, the last of July or in August, 



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