April, '10] 



FELT : THE CODLING MOTH 



175 



An analysis of the records of individual trees in the various plots 

 summarized in the following table, discloses an interesting condition. 



VARIATION IN INDIVIDUAL TREES 



Plot. 



Maximum Tree. 



No. Fruit. 



Per cent 

 Wormy. 



Minimum Tree. 



No. Fruit. 



Per cent 

 Wormy. 



Range in No. of Wormy 

 Fruit. 



1 

 2 

 3 

 4 

 5 

 6 



8,745 

 3,649 

 2,298 

 5,044 

 5,137 

 3,.S21 



2,507 

 226 

 417 



3,002 

 994 

 767 



3.16 

 2.66 

 2.64 

 2.64 

 1.50 

 2.74 



30-111 

 6- 30 

 4- 29 

 36- 80 

 15- 61 

 4- 23 



The maximum tree of a plot invariably produced the lowest or 

 nearly the lowest percentage of w^ormy fruit, while the reverse was 

 true of the minimum tree. It will be seen that the variation in num- 

 ber of wormy apples on the various trees was not very great, indicat- 

 ing a fairly uniform degree of infestation. Were such to be true we 

 would expect a lower percentage, as shown by the figures for wormy 

 fruit, on the heavily laden trees. A reference to the record of the 

 plots as a whole shows practically no variation in the percentages of 

 wormy fruit between the more and the less productive plots. This 

 may be due in part to the fact that the plots sprayed two and three 

 times yielded less fruit than those receiving one application of poison 

 — the smaller yield offsetting in a measure the benefit derived from 

 the second and third sprayings. 



It may be inferred from the above that unusually favoring condi- 

 tions resulted in this somewhat anomalous showing. The first experi- 

 ment, that is, a single application with the Bordeaux and the Ver- 

 morel nozzles was also tried at Kinderhook under different condi- 

 tions, since the trees were older and, moreover, were in the vicinity 

 of still older trees. There is every reason for believing that the 

 codling moth was more abundant in this latter orchard than in the 

 first named. Two plots were laid out in the same manner as at 

 Poughkeepsie and thoroughly sprayed. One plot gave an average 

 of 98.96 per cent of worm free fruit and the other of 98.27, while 

 the check trees produced but 73.08 per cent of worm free fruit. 

 Owing to there being no engine available for these latter experiments 

 and the difficulty of maintaining a suitable pressure by hand, the 



