THE CODLING MOTH ON PEARS IN CALIFORNIA. 51 



RESULTS. 



The fruit from the 10 trees of the unsprayed check block was 95.12 

 per cent wormy and only 4.88 per cent were free from worms. Plat I 

 (Table XLVIII) was sprayed three times and had only 5.80 per cent 

 wormy fruit, with 94.20 per cent free from worms, giving a difference 

 of 88.40 per cent in the amount of fruit free from worms from the two 

 plats. Plat II (Table XLIX), which received the second and third 

 applications (with the first spraying omitted, as given Plat I), showed 

 28.52 per cent wormy fruit and 71.48 per cent free from worms, 

 as against 14.09 per cent wormy fruit and 85.91 per cent fruit free 

 from worms for Plat III (Table L), which received the first and 

 third applications, with the second spraying as given Plat I. 



SUMMARY AND RECOMMENDATIONS. 



There are practically two full broods of larvae in the pear-growing 

 districts of the interior counties of California. Comparatively few 

 of the first-brood larvae go over the winter. 



The number of first-brood larvae being relatively small, the injury 

 is not so noticeable, and many growers overlook the importance of 

 destroying this brood of worms to prevent the greater damage by 

 the more important second-brood larvae, which begin to enter the 

 fruit just prior to the first picking. 



The first-brood larvae begin entering the fruit about a month after 

 most of the petals have fallen, though this time may vary somewhat 

 with the season. All spraying for the first brood should be done 

 within three to four weeks after the blossoms are off the trees. Two 

 applications for this brood reduced the worms for the season from 

 9.62 to 18 per cent lower than the plats sprayed once. 



Two, and preferably three, treatments are advised, using arsenate 

 of lead at the rate of 4 pounds to each 100 gallons of water. The 

 first application should be made as soon as most of the petals have 

 fallen, and especial pains should be taken as nearly as possible to fill 

 each calyx cup with the poison. A tower platform of the type 

 shown in Plate III is very advantageous, because at this time many 

 buds are pointing upward. The trees should be drenched. The 

 second treatment should come three to five weeks after the falling 

 of the petals. The third application should be given nine or ten 

 weeks after the falling of the blossoms, or about two weeks before 

 the first picking begins. If only two treatments can be given, the 

 first and second of the above schedule should be given. 



