60 



BULLETIN 1235, U. S. DEPARTMENT OF AGRICULTURE. 



Table 45. — Wintering period of codling moth larvae 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 



Apr. 10 

 11 

 12 

 14 

 15 

 16 

 17 

 18 

 19 

 20 

 21 

 22 

 25 

 26 



204 

 205 

 206 

 208 

 209 

 210 

 211 

 212 

 213 

 214 

 215 

 216 

 219 

 220 



4 

 5 

 3 

 1 

 2 

 5 

 8 

 8 

 3 

 2 

 7 

 3 

 3 

 2 



1921 



Apr. 27 

 May 1 

 2 

 4 

 5 

 6 

 7 

 8 

 9 

 10 

 11 

 12 

 13 

 14 



221 

 225 

 226 

 228 

 229 

 230 

 231 

 232 

 233 

 234 

 235 

 236 

 237 

 238 



1 

 1 

 1 

 1 

 3 

 6 

 4 

 5 

 7 

 5 

 5 

 8 

 5 

 12 



1921 



May 15 

 16 

 17 

 18 

 19 

 20 

 21 

 22 

 23 

 24 

 29 



June 4 

 6 



239 



240 

 241 

 242 

 243 

 244 

 245 

 246 

 247 

 248 

 253 

 259 

 261 



12 

 6 

 4 



4 

 5 



5 

 2 



7 

 4 

 3 

 1 

 2 

 1 





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 larvae 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. Per cent 



May 6 to June 5, 

 1921. 



Number. Percent 



Aug. 22-31. 

 Sept. 1-15.. 

 Sept. 16-30. 

 Oct. 1-15. . 

 Oct. 16-30. 



Total 



39 

 201 

 140 

 75 

 44 



18 

 135 

 92 

 26 

 14 



499 



285 



57 



30 



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 1921, five unsprayed trees were carefully examined, and 2,780 

 wintering larvae 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 1919, four screen cages were arranged, two of which each had an 

 upright stump with a burlap 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, 



