December, '10] FELT: CODLING moth 475 



30 there was a hail storm (which did not affect series 1 and 2) and an 

 examination showed that from 50 to 60% of the wormy fruit had 

 been entered at points injured by the hail. 



The above tabulation gives a summary which at first sight, at least, 

 compares very unfavorably with the figures obtained in 1909. It 

 will be seen at once that the percentage of clean fruit on sprayed 

 trees varies from 96.84 down to 57.35 or even to 49.33, while the per- 

 centages of sound fruit on the check trees in the various plots range 

 from 43.19 to 28.41. These last figures show at once that the codhng 

 moth was much more abundant in the Hudson valley the past season 

 than in 1909. 



Plots 1 and 2 in series 1 and 2 are respectively nearly comparable, 

 since it will be seen by reference to the table that the percentage of 

 infested fruit on the check trees was nearly the same. Nevertheless, 

 there is a marked decrease in the percentage of sound fruit obtained 

 in series 2, plot 1 yielding over 8% less than plot 1 in series 1, while 

 plot 2 produced some 13% less of sound fruit, this in spite of the fact 

 that the trees in series 2 bore a much larger crop and should normally 

 produce a relatively larger percentage of sound fruit (see Journal 

 Economic Entomology, 3:175). This discrepancy may be explain- 

 able in part by the fact that the orchard in series 1 was younger and 

 somewhat cleaner than that in series 2, though it would seem as if 

 a portion of this difference must be attributed to less efficient spray- 

 ing in series 2, especially as experience has shown that apparently 

 minor inattention to the application may result in a material reduc- 

 tion in the amount of sound fruit. Furthermore, the trees in the 

 orchard of series 2 were somewhat closer together. There was a 

 moderately steep hillside making thorough work somewhat difficult 

 near the experimental trees. The majority of the other trees in the 

 orchard were sprayed but once with Paris green and Bordeaux mix- 

 ture. This application would, in our judgment, hardly be as effec- 

 tive in controlling the second brood of codling moth as the more ad- 

 hesive arsenate of lead. 



A study of the individual trees yields some data of interest. In 

 series 1, plot 1, the number of apples per tree varied from 114 to 627. 

 The percentage of sound fruit ranged from 85.38 to 92.98, while the 

 number of wormy apples produced per tree was 9 to 44 or an average 

 of a little over 29 per tree. It is worthy of note that 8.6% of the total 

 fruit in this plot was side wormy, 7.5% being side wormy only. In 

 plot 2 the number of apples per tree varied from 229 to 980, the per- 

 centage of sound fruit ranging from 93.93 to 97.81 and the number 

 of wormy apples from 5 to- 28, an average of only 15 per tree. There 

 was only a httle over 3.3% of the apples in this plot that were either 



