42 



DECIDUOUS FRUIT INSECTS AND INSECTICIDES. 



The first spraying for Plats I and III was just after most of the 

 petals had fallen from the trees, April 17 to 21. Calyx cups on some 

 of the second-crop fruit were closing at this time. For this spraying 

 the nozzles were held close to the fruit clusters in order to fill the calyx 

 cavities as much as possible. Many counts showed from 80 to 85 

 per cent of all cups to have been filled. The second spraying on 

 Plat I came about three weeks later, May 10 to 12, after the first 

 moths were out and depositing eggs. This spraying was omitted 

 on Plat III. The last spraying was for the second-brood worms and 

 was applied June 28 to 30 on Plats I and III, just after the second- 

 brood moths began to emerge in numbers. 



A gasoline power outfit was used for all sprayings. One man was 

 stationed on a tower platform 8 feet above the tank to spray the tops 

 of the trees while two men sprayed from the ground, supplied with 

 bamboo rods 10 and 12 feet long with large nozzles with wide chambers 

 throwing a mist which spread quickly after leaving the nozzle. A 

 uniform pressure of 150 to 175 pounds was maintained, and arsenate 

 of lead at the rate of 2 pounds to 50 gallons of water was used, re- 

 quiring an average of 2\ to 3 gallons of spray per tree for each appli- 

 cation. 



The total expense of spraying, including the arsenate of lead at 

 12 \ cents per pound, four men to run the machine and do the spraying 

 at $1.50 per day for each man, and two horses at $1 each per day, 

 and gasoline and lubricating oil, etc., amounted to 6^ cents per tree 

 for three applications and 4 \ cents per tree for two applications. 

 The records in Tables XXXVII, XXXVIII, and XXXIX give the 

 comparison of the sound and wormy fruit from 10 trees in each plat 

 for the season. The windfalls were gathered and graded once each 

 week. 



Table XXXVII. — Sound and wormy fruit from 10 pear trees of Plat I, sprayed three 

 times, in orchard of Mr . George Whitman, Concord, Cal., 1909. 





Tree No. 



Number of windfallen 

 pears. 



Number of pears from 

 trees. 



Total number. 



Per cent 

 sound. 





Total. 



Wormy. 



Sound. 



Total. 



Wormy. 



Sound. 



Total. 



Wormy. 



Sound. 



1 



440 



95 



73 



171 



90 



368 



153 



122 



658 



246 



23 



5 



8 



14 



4 



19 



11 



8 



19 



15 



417 



90 



65 



157 



86 



349 



142 



114 



639 



231 



1,294 



1,078 



775 

 1,548 

 1,025 



846 

 1,164 



794 

 1,298 



981 



39 

 34 



24 

 43 

 20 



21 

 22 

 17 

 19 



14 



1,255 

 1,044 



751 

 1,505 

 1,005 



825 

 1,142 



777 

 1,279 



967 



1,734 

 1,173 



848 

 1,719 

 1,115 

 1,214 

 1,317 



916 

 1.956 

 1,227 



62 

 39 

 32 

 57 

 24 

 40 

 33 

 25 

 38 

 29 



1,672 

 1,134 



816 

 1,662 

 1,091 

 1,174 

 1,284 



891 

 1.918 

 1,198 



96.42 



2 



96.68 



3 



96.23 



4 



96.68 



5 



97.85 



6 



96.71 



7 



97.50 



8 



97.28 



9 



98.06 



10. 



97.64 





Total, trees 

 1-10 .. 







2,416 



126 



2,290 



10, 803 



253 



10, 550 



13.219 



379 



12.840 



97.12 



