THE CODLING MOTH IN THE YAKIMA VALLEY. 



73 



Table 61. — Comparison of seasonal history of the codling moth, Yakima, Wash., 



1919, 1920, and 1921. 





Date of — 



Stage and year. 



First. 



Maxi- 

 mum. 



Last. 



Pupation of spring brood : 



1919 



Apr. 8 

 Apr. 3 

 Apr. 9 



May 13 

 May 10 

 May 19 



May 21 

 May 12 

 May ■ 23 



June 7 

 June. 12 

 June 2 



June 23 

 July 6 

 June 22 



July 7 

 July 10 

 July 5 



July 8 

 July 23 

 July 13 



July 15 

 July 27 

 July 15 



July 22 

 Aug. 2 

 July 22 



Aug. 13 

 Aug. 19 

 Aug. 10 



Apr. 27 

 Apr. 26 

 Apr. 17 



May 21 

 June 2 

 May 30 



June 4 

 June 18 

 June 4 



June 18 

 June 28 

 June 8 



July 12 

 July 18 

 July 14 



July 19 

 July 17 

 July 23 



July 19 

 Aug. 15 

 July 31 



July 29 

 Aug. 7 

 Aug. 7 



Aug. 7 

 Aug. 12 

 Aug. 12 



Sept. 3 

 Sept. 4 

 Sept. 5 



May 26 

 May 17 



1920 



1921 



Emergence of spring-brood moths : 



1919 





1920 



July 2 



1921 



Deposition of first-brood eggs: 



1919 





1920 



July 11 

 June 30 



1921 



Hatching of first-brood eggs: 



1919 



June 29 



1920 .- 



July 14 

 July 10 



July 31 

 Aug. 16 

 Aug. 3 



Aug. 12 

 Aug. 15 

 Aug. 15 



Sept. 24 

 Sept. 30 

 Oct. 9 



1921 



First-brood larvee leaving fruit : 



1919 



1920 



1921 



Pupation of first-brood larvss: 



1919 



1920 



1921 



Emergence of first-brood moths : 



1919 



1920 



1921 



Deposition of second-brood eggs : 



1919 



Sept. 20 

 Oct. 10 



1920 



1921 



Oct. 13 



Hatching of second-brood eggs : 



1919 



Sept. 27 

 Oct. 13 



1920... 



1921 



Oct. 2 



Second-brood larvae leaving fruit: 



1919 



Oct. 28 



1920 



Nov. 2 



1921 



Nov. 13 







SUMMARY. 



The seasonal-history studies recorded in this bulletin were made 

 in the Yakima Valley of Washington during the years 1919, 1920, 

 and 1921. 



The codling moth, while not as serious a pest in Washington as 

 it is in some other States, is the most serious and widespread insect 

 pest with which the Washington apple growers have to deal. The 

 climatic conditions are such that two practically complete genera- 

 tions occur, with a very small third generation in some seasons, as 

 evidenced by the data herein. 



A comparative summary of the length of the various periods in 

 the life cycle of the codling moth at Yakima in 1919, 1920, and 

 1921, is given in Table 62. The figures in this table are taken from 

 the individual tables and not from the combined life-cycle tables 

 for each year. 



