REPORT OF THE STATE ENTOMOLOGIST I91O 1 3 



another had prepared a similar retreat for the winter on an apple 

 before it had dropped from the tree. 



Life history and habits. Before discussing the experimental 

 work of the season we will briefly summarize the life history of this 

 species. The apple worm, as is well known, winters in a tough, 

 silken cocoon, usually found under the rough bark of trees. The 

 advent of warm weather in spring, which in New York means late 

 April and early May, is followed by the caterpillars transforming 

 within their silken retreats to pupae, and a week or ten days after 

 the blossoms drop the moths commence to emerge and continue to 

 appear throughout the greater part of June. The minute, whitish 

 eggs are deposited largely upon the leaves, though a number may 

 be found on the young fruit. These hatch in about a week and 

 as a consequence the young apple worms of the first brood may be 

 entering the small apples from early in June to nearly the end of 

 the month, or even later. The caterpillars require about four weeks 

 to complete their growth, at which time they desert the fruit, wander 

 to a sheltered place, spin a cocoon, transform to pupae and in about 

 two weeks, namely the very last of July or in August, another 

 brood of moths appears. These in turn deposit eggs which hatch 

 in due time and the young larvae usually enter the side of the 

 fruit. Two broods appear to be the rule in the northern fruit-grow- 

 ing sections of the United States, though some investigators claim 

 a third in the southwest. 



Experimental work. It v^as planned the present season to 

 test, under varying conditions, the relative efficacy of but one spray 

 given just after the blossoms fall, compared with other plots where 

 the application just described was followed by a second about three 

 weeks later, designed to destroy the codling moth larvae just as 

 they are hatching, and a third plot where but one spraying was 

 given about three weeks after the blossoms fell. This plot was 

 designed to show the relative efficacy between the treatment at this 

 time, which is markedly out of season, and the time applications 

 are usually made, namely just after the bloom falls. 



Series i. This series of experiments were conducted in a young 

 orchard belonging to Mr W. H. Hart of Arlington, near Pough- 

 keepsie and close to Briggs Station on the Hopewell branch of the 

 Central New England Railroad. The orchard is on a moderately 

 high hill, the trees being thrifty, about i6 years old, i6 to 19 feet 



