86 



In most cases this last change does not occur in Massa- 

 chusetts until the following spring, there being but one gen- 

 eration a year. A few of the caterpillars which finish feeding 

 early, however, may undergo this change and produce moths 

 which appear in August, and at once lay eggs for a second 

 generation the same season. The caterpillars which hatch 

 from these eggs enter the fruit at any point and are usually 

 the ones found in late apples M'hen these are gathered, though 

 they may be the very latest members of the first generation. 



The usual method of control for this pest is to spray the 

 trees with arsenate of lead just after the blossoms fall. At 

 this time there is a little depression or cup at the blossom end 

 of the apple, with five green projecting lobes (sepals of the 

 blossom) surrounding it. After about ten dayfe these bend 

 inward and close up the opening of the cup. The caterpillars 

 which enter at the blossom end of the fruit either push their 

 way between or bore through these lobes, enter the cup and 

 start boring their way toward the core from its bottom. If, 

 therefore, poison can be placed in this calyx cup, as it is 

 called, while its top is still open, the caterpillars entering later 

 must feed upon that on their way into the fruit. 



In spraying to accomplish this, therefore, the purpose should 

 be as far as possible to direct the spray against the blossom 

 ends of the little apples and place the poison in the calyx 

 cup. When the lobes close together later, they will aid in 

 preventing rains from washing out the poison before the 

 caterpillars arrive. 

 , A later spraying with arsenate of lead, usually about the 

 15th or 20th of June, is also frequently given. The purpose 

 of this is to poison the leaves on which the caterpillars feed 

 somewhat before going to the fruit. As some of the insects do 

 not enter the fruit at its blossom end but elsewhere, this 

 second spraying is largely for the purpose of killing those 

 which would not be reached bj' the poison in the calyx cup. 



In spraying, use a rather fine nozzle giving small droplets of 

 spray, and considerable pressure at the pump to force the 

 droplets into the calj-x cups as much as possible. Three 

 poimds of the paste arsenate of lead (or If pounds of the pow- 

 der) in 50 gallons of water is the usual mixture for both appli- 



