JOURNAL 



OF 



ECONOMIC ENTOMOLOGY 



OFnCIAL ORGAN AMERICAN ASSOCIATION OF ECONOMIC ENTOMOLOGISTS 



Vol. 9 DECEMBER, 1916 No. 6 



A CODLING MOTH TRAPi 



By E. H. SiEGLER, Entomological Assistant, Deciduous Fruit Insect Investigations 



The control of the codUng moth (Carpocapsa pomonella L.) in the 

 Grand Valley of Colorado has been the most difficult insect problem 

 with which the fruit-grower has had to contend. Time and again, 

 despite five to eight thorough spray applications, a large percentage of 

 the apple crop has annually been destroyed by this pest. The grav- 

 ity of the situation is increased by the fact that no improvement has 

 been made during the past decade. Furthermore, spraying has be- 

 come relatively too expensive for the benefits derived therefrom, and 

 it is quite probable that, unless some auxiliary methods are employed, 

 the situation will remain unchanged. The theory that, on a given 

 tree, the spray will as readily destroy one thousand larvse as one hun- 

 dred is neither logical nor true from a practical viewpoint. Spraying 

 loses much of its profitable effectiveness wherever the worms have not 

 been reduced to comparatively small numbers. Especially is this 

 true under the favorable codling moth conditions of a semi-arid region. 



The difficulty of controlling this insect was fully realized by the 

 writer last season, while engaged in deciduous fruit insect investiga- 

 tions under the direction of Dr. A. L. Quaintance of the U. S. Bureau 

 of Entomology and in cooperation with the Colorado Agricultural 

 Experiment Station. After a rather brief experience with the relative 

 abundance of the codling moth in this district, it was at once apparent 

 that some method of control, supplementary to spraying, must be 

 employed to reduce the number of this pest to a point where spraying 

 would again become effective at a reasonable cost. 



The purpose of this article is not to enumerate the causes which 

 contribute to the wormy orchard conditions, but rather to call atten- 

 tion to a possible means of relief. 



^Published by permission of the Secretary of Agriculture. 



