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MR. KIDDER OF MILTON. I was very much interest- 

 ed in the speaker's statement — which I don't doubt for a 

 moment, because I have arrived there by my own experi- 

 ence — that sprinkling is of no particular good, whereas 

 spraying is useful. Now, I thought that perhaps the speak- 

 er can tell us in a few words why that is the case, because 

 to the casual observer it might seem as if getting the ma- 

 terial on in any shape ought to do the work. Apparently it 

 doesn't, and I think it would be very interesting if we could 

 know why it is necessary to spray and not sprinkle. 



DR. WHETZEL. Well, the gist of the matter is this : 

 If you sprinkle the leaves you do one of two things, either 

 put on large drops at various places on the leaves, or pour a 

 lot of it on, and the result is that most of that runs off. 11 

 you drench a tree, even when you are spraying with a mist, 

 many of the leaves will actually have no fungicide on them, 

 because there will be such a large quantity that it will run 

 off the leaves. If you only put a few large drops there will 

 be many places on that where the leaves are not covered. 

 These spores are not as big as a pin head, but are exceeding- 

 ly small and don 't require very much space in which to germ- 

 inate and grow. They are much smaller than the point 

 of a pin and an area as large as the head of a pin will be 

 ample, even though a big chunk of lime-sulfur or Bordeaux 

 may be quite close to it. Now, when you remember that 

 there are millions of spores in the air and that thousands 

 will fall on the leaves you will see that you are taking 

 large chances when you sprinkle. On the other hand, if you 

 spray and put it on in a fine mist, just to the point of drip- 

 ping but not quite dripping, you have covered the surface 

 of that leaf with many fine drops, and when it dries so 

 closely together on the surface of the leaves the ascosporehas 

 no chance of finding spaces between in which they can fall 

 and germinate. It would be surprising to see how small a 

 space a spore may occupy between two drops of Bordeaux 

 mixture, -and still grow. If you had it under the microscope, 

 with a magnification of say fifty diameters, you could see 



