16 



BULLETIN 189, U. S. DEPARTMENT OF AGRICULTURE. 



First-brood moths began to emerge on July 13, and emergence 

 continued throughout the remainder of July and the fore part of 

 August. Two adults appeared as late as August 29, though emer- 

 gence had practically ceased August 17. The codling moth is very 

 sensitive to weather conditions, its development being especially 

 retarded by cold, and the irregularity in the emergence curve of 

 first-brood moths in figure 8 is due, in part at least, to extreme tem- 

 perature variations of the season. 



Second-brood larvae probably began entering fruit at Hagerstown 

 in 1912, about July 23 to 27. 



BAND COLLECTIONS. 



Altogether 1,706 larvae were taken from the bands at Hagerstown 

 in 1912. (See Table XI.) The trees used were of the York 

 Imperial variety, about 15 years old, smooth bodied and loaded with 

 fruit. Bands were placed in the fore part of June and examinations 

 made every three or four days, beginning June 15. 



Table XI. — Number of larvse of the codling moth taken from the bands and reared at 

 Hagerstown, Md., during the summer of 1912 and the spring of 1913. (See fig. 9.) 



Date of collecting larvae. 



Number of 

 larvae col- 

 lected. 



Number of 

 dead from 

 handling, 

 cannibal- 

 ism, etc. 



Number 



emerged, 



1912. 



Number 

 overwinter- 

 ing. 



Number 

 winter- 

 killed. 



Number 



emerged, 



1913. 



June 29 



11 



4 



7 









July 1 











58 



55 



144 



240 



183 



207 



228 



117 



97 



59 



35 



30 



15 



60 



30 



48 



16 



21 



16 



28 



8 





42 

 28 

 42 

 15 



2 

 10 



2 



16 



3 



75 



172 



137 



136 



151 



95 



79 



47 



30 



28 



5 



29 



22 



26 



7 



14 



12 



20 



6 



7 

 3 



24 

 109 

 137 

 100 

 112 

 40 

 25 

 36 

 23 

 11 



9 



9 



24 



27 



53 



44 



61 



75 



22 



18 



12 



5 



2 



10 



31 



8 



22 



9 



7 



4 



8 



2 





13 



51 



17 



63 



21 





25 



36 



29 



39 





55 







54 



9... 





11 



13 





7 



17 





17 



21 





5 



25 





19 

 2 



19 

 7 

 7 

 8 



13 

 4 



10 



30 





20 



Sept. 2... 





7 



6. 







10.. 





7 



14 





4 



18. 





7 



22 





2 









Total 



1,706 

 100 



448 

 26.26 



148 

 8.68 



1,110 

 65.06 



706 

 41.38 



404 



Per cent 



23.68 







From figure 9 it will be seen that the first larvae appeared under the 

 bands on June 29, the numbers gradually increasing through July. 

 From August 1 to 21 the collections decreased, increasing again 

 slightly after the latter date, and it is probable that second-brood 

 larvae were beginning to leave the apples about this time. Only 

 8.68 per cent of the first-brood larvae transformed to moths, which 

 explains the relatively small second brood of larvae shown in figure 9. 



