156 JOURNAL OF ECONOMIC ENTOMOLOGY [V'ol. 14 



THE CODLING MOTH— A QUANDRAY AND A QUERYi 



By G. \V. Hekkick, Cornell University, Ithaca, N. Y. 



Unquestionably the control of the injuries of the codling moth still 

 constitutes the most important entomological problem confronting the 

 apple grower in his attempt to produce clean, A-grade fruit, at least 

 in Western New York. The serious phase of the problem to-day in the 

 production of smooth fruit consists of the so-called side-worm injury 

 in which shallow, circular, or elongated cavities are eaten out of the flesh 

 of the fruit almost anv-where on the surface of the apple. This phase 

 of injury which has assumed m,ore and more prominence in the last 

 few years has complicated the matter of control and it seems destined 

 to modify our recommendations regarding the number and frequency 

 of the applications of spray material. Indeed, certain entomologists 

 as a result of their experience and observations have already shown a 

 tendency to modify the emphasis which they have heretofore placed 

 on the calyx spray and to extend this emphasis to subsequent applica- 

 tions of poison. 



I was first impressed with the importance and complexity of this 

 whole matter of side injury by Dr. Pettey's data in regard to the work of 

 codling moth on pears in South Africa. His data were first embodied 

 in an unpublished thesis and afterwards partly published as Bulletin 9 of 

 the Department of Agriculture of South Africa (1916). Briefly, Pettey 

 shows that comparatively few larv^ae enter the calyx cup of the un- 

 sprayed Beurre Hardy Pear while a very large number enter the sides. 

 On the other hand, in the case of the Kieffer and Bosc large numbers 

 enter the calyx and a much smaller number go in through the sides, A 

 study of the calyces of these varieties shows that the calyx of the Beurr6 

 Hardy pear remains wide open "wnth a clean base due to the total 

 disappearance of stamens and pistils" while the calyx of Kieffer, for 

 example, shows a very complete closure. Petty concludes "that the 

 greater the degree of closure of the calyx cup the greater the percentage 

 of larvae that enter the calyx proper." This work of Petty 's has cer- 

 tainly been suggestive and may throw some light on the problem of 

 codling moth-control in this country. 



Turning to the problem as it exists in the United States we may well 

 consider briefly the significance of some investigations in this country. 

 For example, Woodworth writing in 1913 said that in the Pajaro Valley 

 in California it was observed that the great majority of th« larvae 

 entered elsewhere than through the calyx and that in Sutter county 



'The nature of this paper is the result of the Secretary's suggestion that those who 

 present papers "will discuss broad general topics rather than those of local interest." 



