148 



you can do him any particular damage. We have at the col- 

 lege and farm two orchards where we have sprayed religi- 

 ously for scale, but we get just as handsome a crop of aphis 

 as any of our neighbors who don't spray. 



MR. STOCKWELL .- Then that means two applications, 

 doesn't it? 



THE PRESIDENT: Not necessarily. It means that if 

 you wait until the aphis is hatched and then start you cati 

 use the dormant strength, and can kill both, the scale and 

 the aphis. But you have only a short time. If you have 50 

 acres of orchard, you can't get over the whole of it. 



MR. MANN: The manufacturers' formula recommends, 

 in the application of arsenate of lead just as the blossoms 

 fall, to add the Black-Leaf-40, half a pint to 50 gallons, I 

 think. I would like to know if that will do the work, be~ 

 cause if it will certainly do it we will spray at that time very 

 thoroughly. I find the Avorst time for the aphis is along 

 after the blossoms have fallen. I don't notice them until 

 later. 



PROF. FARLEY: All I can say is that we have con- 

 trolled it for the past two years, and there is no doubt about 

 it at all. We have killed the aphis that we have had. with 

 that material. I don't say that we have hit every one. It 

 may be that all of those eggs have not hatched at that time. 

 We have put the Black-Leaf-40 on the tree both before the 

 blossoms open, and in the codling moth spray, and in doing 

 that have had very successful practical results in controlling 

 the aphis. We have had very little aphis injury to trees 

 that have had those two applications, whereas on trees that 

 have not had them, we have had a beautiful crop of aphis. 



]\IR. HALE : What proportion of the aphis did you miss? 



PROF. FARLEY: I don't know the exact proportion, 

 but in most cases even the most careful man will let a few 

 i)ranches escape in the center of the tree, and on certain 

 trees he may not spray very thoroughly, and unless he hits 

 the aphis it won't affect him. The aphis isn't going to run 

 out and get in the way of the spraying material. 



