138 Report of Slate Board of Horticulture. 



Forbes* as a result of a very carefully conducted series of experiments 

 covering two seasons, during the first of which cei-tain trees were sprayed 

 eight times, arrived at the conclusion that seventy per cent of the loss 

 commonly caused by the codling moth may be prevented by spraying with 

 Paris green once or twice in early spring as soon as the fruit is set and 

 before it turns downward on the stem; but that "certainly no appreciable 

 effect was produced by spraying during the life of the second brood." 

 Gofff obtained practically the same result. Munson$ as a result of some 

 careful work noted that a large proportion of fruits infested had been 

 attacked by the second brood but concluded that to spray for this brood 

 is hardly practicable. Lodenian§ states that it is not advisable to apply 

 Paris green more than twice in a season unless the rainfall is very heavy 

 or continuous. Practically the same conclusion has been arrived at by all 

 experimenters in the eastern United States. The svibject has been finally 

 summarized by Slingerland|| who concluded that if no rains occur between 

 the time of the application and the closing of the calyx lobes, one spraying 

 just after the blossoms fall is just as effective as half a dozen later 

 applications. 



These conclusions, arrived at as the result of years of observation, and 

 the successful experience of many men are not supported by results ob- 

 tained in this state. Early spraying alone will not save the fruit. It is 

 not only practicable but necessary to fight the second brood. Personally, 

 I am of the opinion that the early applications, soon after the petals fall, 

 are of very little value in the Willamette valley. Here the blossoms usually 

 fall not later than May 10. If the application is to be made before the 

 calyx lobes close, spraying must not be delayed more than a few days 

 after this date. The first larvae enter the fruit at Corvallis rarely before 

 June 25. I have as yet had no analysis made, but in view of our usually 

 large rainfall after the petals drop, I am strongly of the opinion that by 

 the time the first larvae are ready to enter the fruit practically none of the 

 poison of these early sprays remain either in the calyx cup or elsewhere 

 upon the fruit. Nevertheless, contrarj^ to eastern experience though it may 

 be, good results are obtained by the use of the spray pump, by keeping 

 everlastingly at it. To quote from Mr. Smith's article on spraying, in the 

 appendix, "By this sign we conquer." In warmer and dryer portions of 

 the state where the larvae begin to appear sooner the early applications 

 are undoubtedly of great value. Even in the Willamette valley it is not 

 best to omit them until their value has been further tested. 



The comparative value of the different applications can best be shown 

 by reference to the following table which records the result of experimental 

 spraying in the college orchard in 1898. Five rows containing one hundred 

 and thirty-four trees were selected for the experiment. Of these fl'fty failed 

 to pi'oduce fruit, or were early varieties of which no records were kept. 



* Fifteenth Report 111. State Bnt. (1885-1886). 

 t Fourth Report N. Y. Agr. Exnt. Sta. (1SS5). 

 t Report Maine Exnt. Sta. (1891). 

 § Bui. 60. Cornell Fxpt. Sta. 

 II Bui. 142, Cornell Expt. Sta. 



