THE CODLING MOTH ON PEAKS IN CALIFORNIA. 



17 



SPRING BROOD OF MOTHS. 



It is probable that the first adult appeared in 1909 about March 23. 

 On this date an apparently freshly shed pupal skin was found, and 

 another was found in the field on March 27. Bartlett pears were at 

 this time just about in full bloom. The first moths were seen in the field 

 on April 17. During spraying operations in a pear orchard three active 

 moths were seen in the trees in the early forenoon. Others were seen 

 on April 19, and on May 5 several were observed among trees in the 

 corner of the orchard near the packing shed. The first moth appeared 

 at the laboratory on April 9 from the lot of pupae collected in the field 

 March 11 to 22. These pupae were kept in glass jars out of doors, but 

 some were injured, and only three moths emerged, namely, on April 

 9, 13, and 14. The individual records show moths emerging from 

 April 17 to May 30 (detailed in Tables I, II, and III). This material 

 was kept in jars out of doors in the shade. 



On May 6, 1909, several bands which had been on trees over 

 winter were removed, and these, as also the trunks of the trees, exam- 

 ined closely. Thirty-six shed pupal skins were found, but no larvae or 

 pupae, indicating that most of the moths had. emerged by this time. 



In the spring of 1910 moths emerged in numbers somewhat earlier 

 than in 1909. Individuals were seen in the orchard April 9, during 

 spraying, although no moths emerged at the laboratory until April 14. 

 At Suisun, Cal., April 5, while examining the trunks of trees for the 

 presence of larvae and pupae, many apparently freshly shed pupal 

 skins were found on the bark. The next day, April 6, at Oourtland, 

 Sacramento County, Cal., shed pupal skins were even more apparent 

 in comparison with the number of larvae and pupae found on the trees. 

 At this time in the two last-mentioned places the petals had been off 

 the trees for some da} r s, and it is generally conceded that these 

 sections are a week or ten days earlier than in the vicinity of Walnut 

 Creek. Table IV shows the emergence of moths from overwintering 

 larvae at Walnut Creek, Cal, 1909-10. 



Table IV. — Emergence of moths from overwintering larvae, Walnut Creek, Cal., 1909 



and 1910. 





Number of 







Number of 





Number of 





Number of 





moths 







moths 





moths 





moths 



Date. 



emerging — 



Date. 



emerging — 



Date. 



emerging — 



Date. 



emerging — 





1909 



1910 



1909 



1910 



1909 



1910 



1909 



1910 



Apr. 14... 







2 



Apr. 



26... 







5 



May 8... 



1 







May 20... 



1 







15... 







1 





27... 



1 



3 



9... 



5 



2 



21... 











16... 







9 





28... 







3 



10... 



3 



1 



22... 



1 







17... 







9 





29... 







1 



11... 



2 



1 



23... 











18... 







10 





30... 







8 



12... 



1 



1 



24... 



2 







19... 







1 



May 



1... 



2 







13... 



2 







25... 



2 







20... 



2 



9 





2... 



3 



3 



14... 



1 



1 



26... 



3 







21... 



1 



7 





3... 



1 



4 



15... 











27... 



1 







22... 



1 



ii ! 





4... 



4 



1 



16... 











28... 



2 







23... 







5 





5... 



4 



1 



17... 



4 







29.!. 



2 







24... 



1 



9 





6... 



6 



5 



18... 











30... 



2 







25... 













7... 



5 3 



19... 



1 







31... 











