April, '09] JOUnXAL OF ECONOMIC ENTOMOLOGY 157 



l)rown-rot upou their feet or bodies by crawling' lirst over brown-rot 

 ' ' mummies " ' or infected spots and then to non-infected peaches, where 

 they may establish newly-infected areas by making new punctures or 

 passing over old ones. This relation of the eurculio to brown-rot in- 

 fection, many times noted by entomologists, is worthy of further care- 

 ful observations. 



Arsenate of lead undoubtedly also possesses some fungicidal pi-op- 

 erties. Upon apples it has shown such action and in this experiment 

 upon peaches a decided decrease in the amount of peach scab was noted 

 in the sprayed portions over those left untreated. 



An additional gain in improved color of fruit was also secured, 

 which alone was enough to almost repay the cost of spraying. The 

 peaches from the sprayed l)locks where the best results had been se- 

 cured in controlling- eurculio were of a beautiful bright red color, 

 some very dark in fact, making them extremely attractive and adding 

 greatly to their market value. That this color was the effect of the 

 lead arsenate was plain, due in part perhaps to greater exposure of the 

 peaches to the sun by a diminution of the foliage on some trees by 

 spray burning, but chiefly due to direct chemical or physiological ac- 

 tion of the arsenate of lead upon the tissue of the peach. 



In some plats treated the action of the spray was severe enough to 

 cause burning of foliage and fruit and to cause uneasiness as to the 

 outcome. A spray of lime water was given at one time to some plats 

 to arrest this burning action. In some plats, where the very best re- 

 sults were secured in controlling the insect, some peaches showed un- 

 mistakable indications of burning upon the foliage, peaches and small 

 twigs, though from recent observations upon these trees this injury 

 does not appear to have been serious enough to the twigs to materially 

 affect the prospect for fruit upon the trees the coming j^ear. 



We may sum up the results of this preliminary experiment as show- 

 ing the coiuplete possibility of the prevention of the majority of eur- 

 culio injuries by arsenate of lead sprays but leaving some questions of 

 safety to the tree from the spray still unsettled. Some important 

 points bearing upon this were, however, brought out by the experiment, 

 which will be valuable in the investigation continued upon the subject 

 next year. Some of the points thought to be established and worthy of 

 mention are : 



1. The increase of lead arsenate in the spray formula increases 

 the danger of injury. 



2. The addition of lime to lead arsenate for peach spraying reduces 

 the danger of injury. 



3. The use of lead arsenate as dilute as 2 pounds per 50 gallons with 



