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pressure for the first spraying, so as to drive the spray 

 through the trees and into the calyx. Since I have been 

 East I have seen people just spitting the spray at the trees, 

 as you might say, without pressure enough to get at the top, 

 and then saying it didn't do any good to spray. It seems 

 to me that the pressure question in spraying is something 

 that the people here haven't got on to yet. 



DR. FELT. My position in regard to the pressure is 

 this: the higher the pressure, the more rapidly you can do 

 thorough work, but with a pressure of 80 pounds or there- 

 abouts, if you are willing to take the necessary amount of 

 care and can get it all over the tree, I fail to see why you 

 can't secure almost as good results as though the pressure 

 ran up to 200 or 300 pounds. Of course, it takes more time 

 with a pressure of only 80 pounds. In our initial experi- 

 ments we ran a pressure test on six plots, three by spraying 

 with a high pressure of approximately 150 pounds and using 

 a coarse spray with a Bordeaux nozzle adjusted so as to get 

 something that would drive ; and in the other three using a 

 disc nozzle which gives a more uniform spray. We were 

 insistent upon having thorough work especially with the 

 driving spray, because we wanted to give it a good, fair test, 

 and it took longer, so long, in fact, that the man who owned 

 the orchard almost lost patience because we took so much 

 time. With the other spray we went over it rapidly. So 

 far as distributing the spray, the covering was pretty nearly 

 uniform in both series, though I think if we had kept close 

 watch we would have found more used per tree where we 

 employed the heavy pressure, than in the others. On check- 

 ing up at the end of the season I think there was less than 

 one-half of one per cent difference. If you can get 98 or 99 

 per cent with a fine spray, why say anything about the 

 absolute necessity of using a coarse spray and high pressue? 



MR. BILLINGS. Take it on a high tree, how would 

 you get at the high limbs? 



DR. FELT. That is just the point. You have got to 

 have your pole or equipment of the proper dimensions. You 

 have got to have proper distribution. My ideal of spraying 

 for codling moth is not to stand under a tree and shoot up 

 the spray and let it fall down. You must have a nozzle 



