THE CODLING MOTH IN THE YAKIMA VALLEY. 



39 



Table 33. — Length of the pupal stage of pupx of the spring brood of the codling 

 moth, Yakima, Wash., 1921. 







Pupal period in 



days. 







Pupal period in 



days. 



Date of 

 pupation . 



Num- 

 ber of 

 pupa?. 









Date of 

 pupation. 



Num- 

 ber of 

 pupae. 









Average. 



Maxi- 

 mum. 



Mini- 

 mum. 



Average. 



Maxi- 

 mum. 



Mini- 

 mum. 



Apr. 10 



35 



41.46 



43 



40 



May 6 



12 



24.67 



26 



22 



11 



24 



41.38 



43 



40 



7 



9 



23.33 



25 



17 



12 



22 



41.05 



42 



40 



8 



6 



23.83 



25 



23 



13 



9 



39.89 



41 



38 



9 



13 



23.31 



24 



22 



14 



4 



39.00 



39 



39 l 



10 



7 



22.86 



24 



22 



15 



14 



39.07 



49 



38 



11 



7 



22.29 



23 



22 



16 



26 



38.12 



45 



37 



12 



13 



21.77 



23 



21 



17 



33 



37.06 



38 



36 



13 



20 



20.90 



23 



20 



18 



22 



36. 64 



40 



35 



14 



26 



21.00 



24 



20 



19 



11 



36.00 



39 



35 



15 



20 



20. 25 



21 



19 



20 



12 



36.00 



38 



34 



16 



13 



19. &5 



20 



19 



21 



17 



36.06 



37 



33 



17 



19 



19.21 



21 



18 



22 



8 



35.50 



37 



32 



18 



12 



19.25 



20 



18 



24 



8 



33.75 



35 



31 



19 



16 



18.94 



21 



18 



25 



5 



33.40 



34 



33 



20 



13 



18.46 



20 



18 



26 



10 



32.00 



33 



29 



21 



7 



18.43 



20 



17 



27 



8 



31.50 



32 



31 



22 



10 



18.50 



20 



16 



28 



3 



31.00 



32 



30 



23 



7 



18.71 



20 



17 



29 



5 



31.20 



35 



29 



24 



6 



19.33 



21 



18 



30 



4 



28.25 



29 



28 



25 



1 



19.00 



19 



19 



May 1 



9 



28.44 



29 



28 



29 



2 



19.50 



20 



19 



2 



3 



27.67 



28 



27 



30 



1 



13.00 



13 



13 



3 



3 



26.67 



27 



26 



June 1 



2 



21.00 



21 



21 



4 



3 



26.00 



27 



25 



4 



1 



21.00 



21 



21 



5 



11 



25.18 



26 



25 



5 



1 



21.00 



21 



21 



Total number of pupa? 553 



Average length of pupal stage in days 29. 53 



Maximum length of pupal stage in days 49 



Minimum length of pupal stage in days 13 



MOTHS OF THE SPRING BROOD. 



Time of emergence. — Figure 24 indicates graphically the time of 

 emergence of 2,165 spring-brood moths, of which 1,896, or 87.5 per 

 cent, emerged between May 22 and June 6, owing to the high tempera- 

 tures. The result of daily mean temperatures below 55° F. on May 

 26 and 27 is clearly shown in the accompanying diagram. The first 

 moth emerged May 19, and the last moth on June 27, with a maxi- 

 mum emergence of 259 moths on May 30. 



Oviposition by moths of the spring, brood. — The high temperatures 

 previously mentioned created nearly ideal conditions for oviposition 

 by spring-brood moths. Consequently the average number of days 

 before oviposition and from emergence to maximum oviposition was 

 2.47 and 5.53, respectively, which is noticeably less than the same 

 interval in 1919 and 1920. The moths emerging on June 8, which 

 had a maximum of 18 days for each of these periods, were abnormal 

 in that they laid only 4 eggs. Eggs were deposited on the day after 

 emergence in 9 out of 19 instances. The data in Table 34 are for 

 cages rather than individuals. 



