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air settles in around it. 



MR. MUNSON: Two or three men would like to hav,' 

 YOU explain how the apple scab winters or spreads. 



MR. DAVENPORT: In the case of the apple scab we 

 find that the disease is not only on the fruit itself hut on the 

 leaves and also sometimes on the hark of the tree. The 

 falling of the leaves with the apple scab on them and lying 

 on the ground all winter is one of the chief sources of in- 

 fection the following year. The folloAving year when we 

 get the spring rains we find the spores on the leaves are 

 thrown into the air. These spores alight on the leaves and 

 on the little stems of the blossoms just before they open and 

 germinate in the moisture there. These develop and give 

 rise to later infections. 



MR. NORRIS: Do you know anything about the dust 

 spraying? The Cornell Experimental Station. I believe, 

 has tested it out some and a number of the large New York 

 State growers have been using it quite extensively. Is it 

 going to take the place of some of our liquid sprays? 



:\IR. DAVENPORT : The matter of the dust si)ray has 

 not become prominent in Massachusetts at all, yet it has 

 ])ecome quite prominent in some sections of New York State. 

 I do not believe it will ever take the place entirely- of our 

 liquid sprays for the first reason they do not recommend the 

 use of dust sprays on young trees and second they do nor 

 recommend the use of dust sprays at the present time for 

 winter spraying, but only for foliage spraying. Thus if yon 

 are going to do dust spraying, and :f you are going to do 

 liquid spraying, you have got to have two sets of apparatus 

 for spraying which I do not believe is economy on the 

 average place. They claim for dust spraying that it is 

 cheaper on large trees than the licpiid spraying, for it i.^ 

 much easier to get around in the orchard because first the 

 fjpparatus is lighter and second because you do not have the 

 weight of the water. The dust spray machine itself T un- 

 derstand does not get out of order ^ cry easily and that is 

 some advantage. In sections where vou have to draw your 



