212 THE CONNECTICUT POMOLOGICAL SOCIETY. 



the fact that 30,000 peach trees were sprayed with com- 

 mon brands of lead arsenate in Connecticut in 1911. When 

 lead arsenate is added to a lime-sulphur mixture, we know 

 that some chemical action takes place, and the injury is 

 probably due to the result of this action rather than to 

 the lead arsenate itself. 



Moreover, Dr. Jenkins a few years ago showed that 

 when lead arsenate is added to Bordeaux mixture, it be- 

 comes even more insoluble than when placed in water. 

 Dr. Stewart's table does not show that he tried either the 

 Bordeaux mixture or the lead arsenate alone on peach 

 trees. 



Dr. Stewart: We tried those in our first application, 

 and there was no appreciable injury. We used rainwater to 

 cut out anv possibility of getting in any foreign materials 

 from the soil. There was no burnino' when we used only 

 lead arsenate and rainwater for our applications. 



Dr. BrittO'N : We frequently get injury from the Bor- 

 deaux mixture alone in Connecticut. 



Dr. Stewart : Of course, we will get some burning 

 from it on peaches, and that is one of the facts brought out 

 in my paper, as you undoubtedly noticed. 



Dk. Britton : How do you account for the fact that 

 the arsenical causes injury when used in Bordeaux, if it is 

 more insoluble there than in water alone? 



Dr. Stewart: In the Bordeaux mixture, while I have 

 not gone into that fully, we would find it alkaline, and I would 

 not wonder if we found that the same chemical situation oc- 

 curs, or that a reaction occurs which sets free the arsenic. 



Dr. Britton : When Dr. Jenkins made the test, he found 

 that the lead arsenate was more insoluble in Bordeaux 

 mixture than in water alone. 



Dr. Stewart: The only answer I can give to that is 

 this, that in our field results the nature of the injury seems 

 absolutely the same on the fruit, no matter with which of 

 these fungicides we get it. Consequently, it seems to me it 



