156 JOURNAL OP ECONOMIC ENTOMOLOGY [Vol. 2 



yield, a condition naturally expected to favor heavy infestation by the 

 beetles present. 



The Results 



A record of the windfall peaches was secured by collection of fallen 

 fruit under trees carefully selected at the beginning of the experiment 

 from the central portions of each plat, so as to minimize the compli- 

 cations in the results otherwise likely to follow from the spreading of 

 the beetles from one block to another. From these indicated trees the 

 ripened peaches were picked on July 31st. 



At the time of the picking of the fruit 86% of the peaches in the 

 luisprayed block had fallen to the ground, 94% of them being wormy, 

 as determined by cutting open each peach in making the examinations. 

 Of the few remaining peaches left upon the unsprayed trees at picking 

 time every one was found to have been injured by curculio. 



In one plat which received three applications of lead arsenate, the 

 first at the time the petals had fallen, the second thirteen days later, 

 when the "shucks" or dried calyces were shed from the peaches, and 

 the third eleven days later, gave 87% of the picked peaches free from 

 curculio injury. 



Another plat, which received onl_y two applications of lead arsenate, 

 the latter two as given in the plat just cited, — one when the "shucks" 

 were shed and another eleven days later, — gave 89% of the picked 

 peaches free from curculio injury. 



In still another plat, which received three sprayings of arsenate of 

 lead, one when the "shucks" shed from the peaches, another thirteen 

 days later, and a third eleven days after the second, yielded 94% of 

 the peaches free from curculio, and the best results of all. 



It will be seen that a most remarkable improvement was secured by 

 the spraying in the prevention of damage by curculio ; a much greater 

 ditference than I had expected or even hoped for at the beginning of 

 the experiment. 



A secondary beneficial effect was secured in the control of brown- 

 rot and peach scab. In the unsprayed block 61.3% of the picked 

 peaches counted showed brown-rot infection and in practically every 

 case the infection surrounded a puncture made by a curculio. In the 

 plats Avhere curculio was controlled most successfully brown-rot caused 

 practically no damage. In one case where the curculio injury was re- 

 duced to 13.3% the brown-rot was reduced to 3.8%, and in another 

 plat where curculio was reduced to 11.4% brown-rot was reduced to 

 2.3%. 



It is almost certain that the adult curculios convey the spores of 



