APPLE INSECTS 37 



In feeding and in excavating the egg-cavity very little of the 

 skin is swallowed ; it is merely torn back out of the way. This 

 is one reason why it is so ilifficult to kill the beetles with an 

 arsenical spray. 



In southern Illinois oviposition extends from late May to 

 about the middle of July, and the average number of eggs laid 

 by each female is about 65. The eggs hatch in four or five 

 days and the larva feeds on the pulp, becoming full-grown in 

 about 20 days. When full-grown it is nearly one half inch in 

 length, footless, and owing to the enlargement of certain seg- 

 ments on the back is so strongly curved that it is unable to 

 straighten out. It pupates within the cavity in which it has 

 fed and in about one week the beetle emerges. The new brood 

 of beetles, unlike the plum curculio, feed very little, but go into 

 hibernation by the first of August. 



Remedial measures. 



Spraying with an arsenical as is practiced for the codlin- 

 moth will destroy a small percentage of the apple curculios, 

 but extensive experiments in Illinois have shown that addi- 

 tional applications for the curculios do not kill enough to pay 

 for the expense incurred. (Curculios thrive in overgrown, 

 crowded, unpruned and uncultivated orchards, and may best 

 be controlled by remedying these conditions. The trees should 

 be pruned so as to admit as much sunlight as practicable, the 

 ground should be kept free from weeds and the trees should not 

 be so close together as to shade the entire ground. A large 

 proportion of the infested apples drop and the insect completes 

 its development in the fallen fruit. It is necessary, however, 

 that the fruit remain in the shade, since even a few hours of 

 direct sunlight is fatal to both larvse and pupse. Where the 

 ground has been kept clean and smooth it will pay to rake the 

 windfalls out into the sun, where they will dry up. This should 

 be done early in the season, for great numbers of curculios 

 develop in small apples not larger than a pea. Wild thorn 



