14 NEW YORK STATE MUSEUM 



Life history and habits. Before giving the details of the ex- 

 perimental work, it may be well to outline the life history of this 

 pest, since a knowledge of its habits is essential to satisfactory con- 

 trol work. The apple worm or codling moth, as is well known, 

 winters in a tough, silken cocoon, usually located under the rough 

 bark of trees. With the appearance of warm weather in the spring, 

 which in New York State means late April and early May, the 

 caterpillars transform within their silken retreats to brown, appar- 

 ently lifeless pupae, and a week or ten days after the blossoms fall 

 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. They hatch in about a week and, as a consequence, 

 the young apple worms of the first brood may be entering the small 

 fruit from early in June, approximately three weeks after the 

 blossoms fall, 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, 

 sometimes excavate an oval cell in the wood or bark and spin a co- 

 coon. They transform once more to pupae and in about two weeks, 

 namely the last of July or in August another brood of moths may 

 appear. These in turn deposit eggs which hatch in due time and the 

 young larvae usually enter the side of the fruit. Two broods ap- 

 pear to be the rule in the northern fruit-growing sections of the 

 United States, though some investigators claim a third in the south- 

 west. 



Experimental work. May 29th two lots of trees were sprayed 

 on the farm of Thomas Albright, New Baltimore; 2 pounds of 

 arsenate of lead (15 per cent arsenic oxid) being used to 50 gal- 

 lons of water and 1 gallon of a lime-sulphur wash to 40 gallons of 

 spray. A straight discharge variable nozzle was used on one line of 

 hose, while the other was equipped with two angle Friend nozzles, 

 the extensions in each case being about 8 feet long. 



Plot 1 comprised five moderate sized Ben Davis trees just back of 

 the house and southwest of the barn. These trees are about 18 

 feet high with a spread of 20 to 25 feet and were well loaded 

 with young apples, except tree C, one-half of which bore practically 

 no fruit. The blossoms had mostly fallen, only a few remaining 



