INSECTS AND THEIR CONTROL 229 



pupae, the adult moths emerge and deposit their eggs on the 

 leaves of the apple or pear and occasionally on the newly 

 formed fruits. The young insects hatch from these eggs, eat 

 into the fruit and remain there in the larval form until fully 

 grown. This requires about three weeks. They then leave 

 the fruit, pupate, and change into the moth stage. 



Eggs for the second brood are now laid and the larvae go 

 through the same cycle as did the first. In those regions 

 where there are only two broods in the year, the larvae of 

 this second brood live through the winter as already described. 

 In some of the apple-growing sections of the United States, 

 where the season is long, a third brood may develop in the 

 summer or early fall. 



In this entire cycle, there is just one vulnerable point. 

 This is the point at which the young larva starts to enter the 

 apple. The egg hatches just about the time the petals drop 

 in the spring. Very soon after that the young larva crawls to 

 the blossom-end of the apple, and there enters through the 

 calyx-tube. It must eat its way in to gain access to the in- 

 terior of the fruit. This is the point at which it can be caught. 

 A poison spray applied to the apple in such a way as to cover 

 the open calyx end will kill practically all of the young worms. 

 To do this, however, it is necessary that the spray be applied 

 before the calyx-tube closes. If the spraying is delayed too 

 long, it is impossible to get the poison material inside the 

 closed calyx-tube, the insect finds its way between the sepals 

 of the calyx-tube, and thence eats into the apple, without 

 coming in contact with any of the poison. A spray delayed 

 two weeks may, therefore, be entirely ineffectual; but if the 

 material is applied at just the correct time, the number of 

 apples infested with worms will be very small indeed. 



340. Control. The codlin-moth is controlled by spraying 

 with some arsenical poison, the most common of which is 

 arsenate of lead. This material is applied at the strength of 

 three pounds of paste or one and one-half pounds of powdered 



