THE CODLING MOTH IN THE YAKIMA VALLEY. 



25 



Table 20. — Length of life of male and female codling moths of the spring brood, 



Yakima, Wash., 1920. 



Male. 



Female. 



Male. 



Female. 



Male. 



Female. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Length 

 of life. 



Num- 

 ber of 

 moths. 



Days. 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 11 

 12 

 13 

 14 

 15 

 16 



4 



10 



6 



9 



7 



9 



20 



12 



19 



13 



16 



17 



20 



26 



18 



Days. 

 2 

 3 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 11 

 12 

 13 

 14 

 15 

 16 



2 



8 



3 



5 



4 



6 



12 



11 



15 



18 



16 



23 



26 



38 



24 



Days. 

 17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 25 

 26 

 27 

 28 

 29 

 30 

 31 



18 

 15 

 12 

 12 

 11 

 11 

 4 

 16 

 10 

 8 

 4 

 5 

 6 

 

 4 



Days. 

 17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 25 

 26 

 27 

 28 

 29 

 30 

 31 



21 

 33 

 17 

 20 

 20 

 16 

 14 

 20 

 12 

 16 

 17 

 12 

 9 

 3 

 7 



Days. 

 32 

 33 

 34 

 35 

 36 

 37 

 38 

 39 

 40 

 41 

 43 

 45 



Total. 



4 

 2 

 2 

 4 

 4 

 1 

 2 

 1 

 1 

 3 

 2 

 



Days. 

 32 

 33 

 34 

 35 

 36 

 37 

 38 

 39 

 40 

 41 

 43 

 45 



Total. 





 3 

 1 

 1 

 

 

 

 

 

 

 

 2 



368 



455 



Average length of life of male moths, 16.65 days; female moths, 17.73 days. 

 Maximum length of life of male moths, 43 days; female moths, 45 days. 

 Minimum length of life of male moths, 2 days; female moths, 2 days. 



THE FIRST GENERATION. 



EGGS OF THE FIRST BROOD. 



Time of egg deposition. — Spring-brood moths began ovipositing 

 May 12, but owing to cold weather very few eggs were deposited 

 before May 31, as shown in Figure 14. From then on eggs were 



Fig. 14. — Time of deposition of eggs of the first brood of the codling moth at Yakima, Wash., 1920. 



deposited daily until July 11, with a maximum on June 18, 14 days 

 later than the 1919 maximum. The temperature curve in Figure 14 

 shows for each day the average temperature for the period between 

 3 p. m. and 9 p. m., as this is the period during which most of the 

 eggs are deposited. 



Length of incubation. — Observations were made on 1,010 eggs for 

 the length of incubation. These and other data on the development 

 of the eggs are given in Table 21, 



