THE CODLING MOTH IN THE YAKIMA VALLEY. 



53 



Table 44. — Length of feeding period of wintering larvse, of the second brood of the 

 codling moth, Yakima, Wash., 1921. 







Feeding period in days. 







Feeding period in days. 



Date of 

 entering 



Num- 

 ber of 









Date of 

 entering 



Num- 

 ber of 





















fruit. 



larvae. 



Average- 



Maxi- 

 mum. 



Mini- 

 mum. 



fruit. 



larvae. 



Average. 



Maxi- 

 mum. 



Mini- 

 mum. 



July 22 



7 



24.14 



29 



19 



Aug. 15 



30 



42.96 



56 



29 



23 



1 



20.00 



20 



20 



16 



14 



39.93 



58 



31 



25 



5 



21.40 



22 



20 



17 



11 



43.00 



55 



28 



26 



1 



20.00 



20 



20 



18 



12 



44.58 



51 



34 



27 



6 



25.50 



40 



21 



19 



6 



38.17 



54 



17 



28 



3 



17.67 



18 



17 



20 



9 



42.11 



47 



33 



29 



11 



20.64 



28 



18 



21 



7 



47.00 



52 



42 



30 



20 



26.65 



41 



20 



22 



15 



48.80 



65 



39 



31 



14 



23.71 



26 



20 



23 



6 



42.83 



48 



38 



Aug. 1 



19 



22.68 



29 



17 



24 



8 



48.75 



71 



42 



2 



13 



25.08 



31 



20 



25 



2 



54.50 



62 



47 



3 



18 



27.72 



40 



21 



26 



3 



56.33 



64 



46 



4 



38 



26.37 



48 



19 



27 



10 



48.00 



61 



43 



5 



25 



28.80 



49 



19 



30 



3 



47.00 



59 



39 



6 



30 



27.97 



44 



21 



31 



4 



52.75 



58 



43 



7 



28 



28.25 



44 



19 



Sept. 1 



3 



63.00 



72 



55 



8 



14 



27.43 



36 



19 



2 



4 



63.50 



70 



56 



9 



24 



27.13 



40 



19 



3 



3 



60.33 



71 



50 



10 



27 



30.96 



54 



12 



4 



4 



63.00 



66 



60 



11 



18 



32.83 



49 



23 



6 



1 



61.00 



61 



61 



12 



32 



35.34 



48 



26 



7 



3 



58.67 



61 



54 



13 



26 



36.62 



60 



14 



15 



1 



56.00 



56 



56 



14 



19 



39.89 



61 



28 



19 



1 



39.00 



39 



39 



Total number of larvae 559 



Averagelength of feeding period in days 34. 02 



Maximum length of feeding period in days 72 



Minimum length of feeding period in days 12 



Transforming larvae of the second brood. — Five transforming second- 

 brood larvae which left the fruit between August 10 and August 25 

 had an average feeding period of 16.6 days. The average length of 

 the cocooning period of four of these larvae was 2.5 days. From the 

 resulting pupae, three female moths emerged, after passing through 

 an average pupal period of 17.67 days. The length of the life cycle 

 of the second brood was not computed, owing to the small number 

 of transforming larvae. These moths deposited 43 infertile eggs. 



CODLING-MOTH BAND STUDIES OF 1921. 



Band-record studies were continued in the Guthrie orchard at 

 Yakima in 1921. Twelve of the larger trees were scraped and banded, 

 and 3,666 larvae were collected during the season. The first larvae were 

 found under bands on June 22. The last collection was made on 

 October 14, after the fruit was harvested. Although there is some 

 overlapping of broods in the band collections, the insectary studies 

 indicate that August 9 may be considered the arbitrary division 

 point between the first and second broods of larvae. Accordingly, 

 the maximum collection for the first brood was 149 larvae on July 22, 

 and for the second brood 179 larvae on August 30. 



The results of these studies are given in Figure 31. 



No band-record studies were made in the Walden orchard in 1921. 



A summary of the seasonal history of the codling moth for 1921 

 is shown in Figure 32. 



