228 
JOURNAL OF ECONOMIC ENTOMOLOGY 
[Vol. 11 
early in July. The first hatching eggs were noted on May 31. The 
average maximum temperature during July was about 6 degrees below 
normal which apparently retarded the development of the insects dur¬ 
ing this time. The first moths of the second generation issued July 
26 and eggs were first noted August 10—14 days after the egg hatching 
of 1914. Growers were advised to have their spray on by the 12th 
or 15 days later than was recommended the preceding year. 
The year 1916 proved to be one of more irregularities in the habits of 
the codling moth than of any ever previously studied by the writer. 
Spring and early summer seasons were very far from normal. The spring 
and early summer was cold and accompanied by many rainy days, and 
late summer, though fair weather prevailed, at no time did it become 
warm. The first moths issued in the breeding cages May 26 or at prac¬ 
tically the same time eggs were present on the trees during the two 
preceding seasons. Emergence of moths was at its height between the 
6th and 15th of June. On June 10 the first eggs of the season were ob¬ 
served. Beginning with the 17th of June (at which time egg deposi¬ 
tion should have been at its height) rainy weather conditions set in 
which continued until July 4. During this time temperatures were 
very low, there being only five days during this period at which time 
the thermometer registered above 60 degrees at sunset (the theoretical 
minimum temperature required by the codling moth for the deposition 
of eggs). Of these five days, three registered 62 degrees. Eggs of the 
first generation were found present on the fruit as late as the 8th of 
August but at no time during the summer were they numerous. 
Moths of the second generation were found for the first time on 
August 18, exactly one month later than in 1914 and 22 days later than 
in 1915. But very few second brood moths appeared in 1916; for the 
most part but one generation occurred. This definite statement can 
be made due to results of breeding experiments conducted to determine 
this point. Those worms which resulted from eggs deposited prior to 
the cold, rainy weather which extended from June 16 to July 4 pro¬ 
duced second generation insects; those insects resulting from eggs de¬ 
posited following this cold period failed to undergo any changes after 
they left the fruit and remained as larvae on the trees until the spring 
of 1917. 
The year 1917 was productive of still different irregularities in cod¬ 
ling moth behavior. The past season has been one accompanied by 
heavy losses in many northwestern apple growing sections due to the 
great numbers of worms. Hood River was apparently more fortunate 
than most of the sections in this repsect but nevertheless losses in a 
good many orchards were serious. 
In 1917 the early season was very backward, March, April and May 
