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MR. MUNROE MORSE. I would like to inquire if 

 cultivating the land under the apple trees and burying the 

 leaves would have any effect in preventing that scab? 



DR. WHETZEL. I expected you to ask that question. 

 Yes, it would have considerable effect, depending on how 

 thoroughly you turned under the leaves and when you did 

 it. If you plowed in the fall and did a thorough job you 

 would very greatly reduce the amount of infection the fol- 

 lowing spring ; if you did not plow until spring and plowed 

 so late that the spores were already discharged, you 

 wouldn't gain anything. On the other hand, while this is a 

 good sanitary measure to be employed in the control of ap- 

 ple scab, you must not depend on it alone. We have records 

 in certain orchards in New York State that have been 

 plowed and cultivated, in which the check (unsprayed) ap- 

 ple trees were in the middle of the orchard, and have been 

 thoroughly sprayed, by the way, for 12 years — 98 per cent 

 of the fruit showed scab, even though the land had been 

 thoroughly cultivated and the orchard thoroughly sprayed 

 the season before. It merely shows that there were a few 

 leaves sticking aroimd that hadn't been turned under, those 

 tliat were in the fence corners and under the trees, which 

 would have sufficient spores in them if the season was fav- 

 orable to give a large percentage of scab. Of course, 98 per 

 cent doesn't mean badly spotted, but it was that 98 per 

 cent showed one or more spots. Plowing under is a good 

 sanitary precaution, but not to be depended on, nor are you 

 to omit the spraying. 



A VOICE. How about burning? 



DR. WHETZEL. It might work, except that you 

 would have the same objection that you couldn't thoroughly 

 burn every leaf, and I am inclinde to think you would be 

 discouraged if you should try. It is dangerous to the trees 

 if you put around enough straw to burn all the leaves. If 

 ,>ou get the leaves thoroughly dry, it would be more effec- 

 tive than plowing under and would probably kill a great 

 many spores on leaves which were not actually barned up. 



