Insect and Disease Control 221 



Methods of control of curculio. 



Jarring. — The habit of the beetles in dropping to the 

 ground, especially in the cool of early morning, feigning death, 

 when a branch on which they may be resting is suddenly 

 jarred, was formerly taken advantage of in collecting large 

 numbers of the adult insects during the period when egg- 

 laying was proceeding most rapidly. Various devices for 

 catching the beetles have been used more or less. However, 

 this method has largely given place to spraying with arsenate 

 of lead and is no longer much used by commercial growers. 



Cultivation. — Because of the fragile nature of the pupae, 

 frequent tillage during the period when the larvae are trans- 

 forming into adults may reasonably be supposed to destroy 

 many of them. In the latitude of Washington, the larvae 

 are beginning to enter the ground to pupate in about six 

 weeks, and in Illinois about eight weeks, after the blossom- 

 ing period. This continues for several weeks or even months, 

 but much more rapidly during the first four or five weeks 

 after the process begins than later. During this period 

 tillage will be the most effective in destroying the pupae. 



Poisons. — The adult beetle feeds on the fruit and foliage, 

 both early in the season and later after it emerges from the 

 pupa. This offers an opportunity to reach many of the 

 insects by spraying the trees with arsenate of lead. It is 

 applied at the rate of 2 pounds to 50 gallons of water 

 with 2 to 3 pounds of lime added, or it may be used in a 

 like quantity of self-boiled lime-sulfur mixture as a com- 

 bination spray for both insects and diseases. The direc- 

 tions for making the necessary applications are given in 

 the spraying program on pages 290-292. It is the convic- 

 tion of some that the effective control of the curculio con- 

 tributes very materially to the control of brown-rot by 



