REPORT OF THE STATE ENTOMOLOGIST IC)I2 



23 



amount placed upon the foliage if a second spraying be given dur- 

 ing this period, as will be seen shortly, is of comparatively small 

 value in destroying codling moth larvae. 



Summary of four years' work with one spray for the codling moth 



PLOT 



SERIES 



YEAR 



I 



4 



I 



4 



■7 



1 



1 



1 



1 



1 



2 



1 



1 



2 



2 



2 



1 



2 



1 



2 



1 



2 



1909 

 1909 

 1909 

 1909 

 1909 

 I9IO 

 I9IO 

 I9II 

 I9II 

 1912 

 1912 



Grand to 



tal 









TOTAL 

 FRUIT 



CLEAN FRUIT 



Total 



30177 

 20313 

 21264 

 9852 

 I909I 

 1839 

 .8135 

 16638 

 20802 

 III38 

 10029 



29818 

 20017 

 21042 



9683 

 I86I7 



1664 



6677 

 I65I5 

 204OI 

 10833 



9898 



I69278 16516S 



Per 



cent 



98. 



97.56 



WORMY FRUIT 



Total 



Per 



cent 



359 

 296 

 222 

 169 

 474 

 175 

 1458 

 123 

 401 

 305 

 131 



1. 19 



1-45 

 1.04 

 1.73 

 2.48 

 9-52 

 17.92 

 • 74 

 1.93 

 2.74 

 1. 31 



End 

 wormy 



33 

 31 

 23 

 19 

 SI 

 16 

 160 

 19 

 28 

 14 

 13 



4113 



2-44 



407 



End 

 and 

 side 



wormy- 



Side 

 wormy 



Per 



cent 



end 



wormy 



308 

 259 

 181 

 137 

 391 

 138 

 1271 

 92 

 359 

 275 1 

 105 



35i6, 



The above tabulation shows that one spray 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 ex- 

 planation it should be stated that the figures for several plots in 

 1909 were omitted simply to give a more nearly equivalent value to 

 the returns obtained for the four-year period. Attention should be 

 called to the 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 1910, the lowest per- 

 centage of sound fruit obtained from one spraying was 97.52. It 

 is worthy of note that only a little over ^ of 1 per cent (.353 per 

 cent) of the wormy apples were end wormy. This, compared with 

 the proportion of end wormy on the unsprayed trees, which latter 

 amounts to 21.73 P er cent > shows that the great reduction in wormy 

 fruit was due to the destruction of the caterpillars or apple worms 

 attempting to enter the apples at the blossom end, and indicates in 

 a striking manner the importance of this early spray. The contrast 

 is more evident if we raise the yield of the check or unsprayed trees 

 to approximately that of the sprayed trees and the other data pro 



