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nate of lead. One of the astonishing features at our last 

 meeting at Poughkeepsie was the fact that growers in the 

 Hudson River Valley seemed to be against powdered 

 arsenate of lead, when in previous 3'ears they were in favor 

 of it. It seems as though their attitude toward powdered 

 arsenate of lead in that case was developed by the fact that 

 they had been using during that season one or two grades 

 of powdered lead which were rather coarse, apparently 

 settled quickly; in other words the material was a coarse 

 powder. You do not wonder that after an experience of 

 that kind with powdered arsenate of lead, they returned to 

 the use of paste arsenate of lead. Now when it comes to 

 relative efficiency, I think there is no x{uestion at all that 

 cne is just as efficient as the other. If you are going to use 

 l)0wdered arsenate of lead, secure one of those grades of the 

 tjnely divided, fluffy sort and avoid those grades in which 

 the powder is coarse and shot-like. 



A i\IEMBER: I would like to ask Prof. Parrott if he 

 <;an give us anything on the new arsenate spray or arsenate 

 of lime? 



PROF. PARROTT : Well, there are two arsenical prep- 

 arations that have come to the front in recent years, calcium 

 arsenate and zinc arsenite. When you consider cost and 

 economy and safety, neither are to be preferred to arsenate 

 of lead, at least for fruit trees. 



A MEMBER: I understood that the lime arsenical is a 

 cheaper form. 



PROF. PARROTT : It is somewhat cheaper and yet for 

 the spraying of orchards it is not regarded quite as safe as 

 the arsenate of lead. In the case of potato spraying. I 

 believe calcium arsenate or zinc arsenite might be preferred 

 to arsenate of lead, because their toxic properties are 

 manifested more quickly than that of lead arsenate, but 

 for orchard use I think preference is still to be given to 

 arsenate of lead. 



A MEMBER: The sinuate borer has become a consider- 

 able pest. 



