April, '13] CODLING MOTH DISCUSSION 175 



It will be seen that the check plots during this four-year period 

 gave an average percentage of sound fruit amounting to 67.99, the 

 yield in individual plots varying from 28.41 to 85.06 per cent. The 

 average percentage of end wormy fruit for these plots is 21.73, a marked 

 contrast to what was obtained from the sprayed trees. The returns 

 from these check trees may be briefly summarized as follows: Ap- 

 proximately one third of the fruit was wormy and nearly two thirds of 

 the wormy apples were entered at the end or end wormy. 



The above data show that one spraying during this period produced 

 from 82.08 to 99.26 per cent of sound fruit or an average of 97.56 

 per cent for the four years when comparisons are made between an 

 equal number of plots in each year. In explanation it should be stated 

 that the figures for several plots in 1909 were omitted in calculating the 

 averages simply to give more nearly equivalent values to the returns 

 obtained for the four year period. Attention should be called to the 

 relatively low percentages of 1910, a season remarkable for the unusual 

 destructiveness of the second brood and one presenting infrequent 

 conditions which were further accentuated by the small yield of that 

 year. Excluding the data for that season, the lowest percentage of 

 sound fruit obtained from one spraying was 97.52. It is worthy of 

 note that only a little over one third of 1 per cent (.353 per cent) of 

 the wormy apples were end wormy, a striking contrast to the 21.73 

 per cent end wormy on the check or unsprayed trees. 



A study of the above data justifies the conclusion for the Hudson 

 valley at least, that in normal seasons when the crop is abundant or 

 fairly so, one thorough early spraying within a week or ten days after 

 the blossoms fall and preferably early during that period, should 

 result in securing from 95 to 98 per cent of sound fruit. Our data 

 show that the benefit resulting from two later sprayings is compara- 

 tively small so far as controlling the codling moth is concerned though 

 ample to meet the cost of the posion and, in many instances, probably 

 the expense of treatment. 



President W. D. Hunter: This paper, which has well summarized 

 an important line of work, is now before you for discussion. 



Mr. W. E. Britton : Whether we use one or more sprayings against 

 the codhng moth will depend upon local conditions. In Connecticut 

 there are several neglected orchards where 80 per cent of the unsprayed 

 fruit shows codling moth injury. In other orchards which have been 

 sprayed for several years there may be not more than 10 per cent of 

 wormy unsprayed fruit. Last fall I saw a tract of land in Connecticut, 

 purchased twenty years ago as an abandoned farm. It was rough 

 and grown up to bushes. Fifteen years ago some of the land was 



