60 



BULLETIN 1235, U. S. DEPARTMENT OF AGRICULTURE. 



Table 45. 



Wintering period of codling moth larvx of the second brood collected 

 under bands at Yakima, Wash., September 18, 1920. 



Date of 

 pupation 



Winter- 

 ing period 

 in days 



Number 



of in- 

 dividuals 



Date of 

 pupation 



Winter- 

 ing period 

 in days 



Number 



of in- 

 dividuals 



Date of 

 pupation 



Winter- 

 ing period 

 in days 



Number 



of in- 

 dividuals 



1921 







1921 







1921 







- Apr. 10 



204 



4 



Apr. 27 



221 



1 



May 15 



239 



12 



11 



205 



5 



May .1 



225 



1 



16 



240 



6 



12 



206 



3 



2 



226 



1 



17 



241 



4 



14 



208 



1 



4 



228 



1 



18 



212 



4 



15 



209 



2 



5 



229 



3 



19 



243 







16 



210 



5 



6 



230 



6 



20 



244 



5 



17 



211 



8 



7 



231 



4 



21 



245 



2 



18 



212 



8 



8 



232 



5 



22 



246 



7 



19 



213 



3 



9 



233 



7 



23 



247 



4 



20 



214 



2 



10 



234 



5 



24 



248 



3 



21 



215 



7 



11 



235 



5 



29 



253 



1 



22 



216 



3 



12 



236 



8 



June 4 



259 



2 



25 



219 



3 



13 



237 



5 



6 



261 



1 



26 



220 



2 



14 



238 



12 













176 





Average number of days in wintering period 229. 79 



Maximum number of days in wintering period 261 



Minimum number of days in wintering period 204 



Table 46. 



■Time of pupation of wintering larvx of the second brood of the codling 

 moth, Yakima, Wash., 1921. 



Date of leaving fruit. 



Number 



of in- 

 dividuals. 



Date of pupation. 



April 9 to May 5, 

 1921. 



Number. Percent 



May 6 to June 5, 

 1921. 



Number. Per cent 



Aug. 22-31. 

 Sept. 1-15.. 

 Sept. 16-30. 

 Oct. 1-15. . 

 Oct. 16-30. 



Total 



39 

 201 

 140 

 75 

 44 



18 

 135 

 92 

 M 



it 



67 



499 



2v3 



57 



214 



EMERGENCE OF MOTHS FROM THE SOIL. 



In the Yakima Valley a considerable number of wintering codling- 

 moth larvae spin their cocoons in the soil about the bases of the 

 trees. Most of these cocoons are found in the first inch or two of 

 soil and immediately adjacent to the trunk of the tree. (PI. Ill, fig. 2.) 

 Examinations of trash, and soil away from the trunk of the tree 

 have failed to show any appreciable number of cocoons. In the fall 

 of 11)21, five unsprayed trees were carefully examined, and 2,780 

 win t eiing larva; were collected. Of these, 578, or 21 per cent, were 

 in the soil, 



On account of the large number of worms cocooning in the soil, 

 it was thought desirable to ascertain what effect this fact has on the 

 emergence of the spring brood of moths. Accordingly, in the fall 

 of L919, four screen cages were arranged, two of which each had an 

 upright stump with a bur-lap band around it secured to the floor 

 to simulate a, banded orchard tree. The other two were each equipped 

 with an upright piece of wood in the same position as the stump, 





