44 



BULLETIN 189, U. S. DEPARTMENT OF AGRICULTURE. 



TABLE XL. Effect of differences in altitude and latitude on the time of appearance of 

 spring-brood and first-brood codling moths and first-brood larvx Continued. 



RELATIVE NUMBERS OF LARV^ ASCENDING AND DESCENDING THE 



TREES. 



In 1911 several trees in a number of orchards were banded around 

 the trunks and also around the bases of the larger branches. The 

 lower bands were used to secure larvae that had dropped with the 

 infested fruit and ascended the trunk to spin up, and the upper 

 bands were used for those that left the fruit before it dropped and 

 descended toward the trunk for the same purpose. The following 

 table shows the relative number of larvae secured under the two sets 

 of bands in the six orchards. In considering Table XLI due allow- 

 ance should be made for an unknown number of larvaB that crawled 

 across the bands or that spun up under the bark before reaching the 

 bands. 



TABLE XLI. Relative numbers of codling-moth larvx collected from bands around the 

 trunks and bases of branches, season of 1911. 



