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Plant Sanitation. 



of caustic potash and soda, over which it appears to have some advantage, 

 particularly as a partial preventive to scab. So far as personal experience indi- 

 cates, the caustic potash and soda, used year after year as a spraying mixture 

 in February, have no effect whatever as a preventive of scab, apple-sucker, or 

 aphis, valuable though they are for cleansing the trunks and branches of the 

 trees of moss, lichen, and American blight, and possibly for destroying hiber- 

 nating insects and eggs. The attacks of the apple-sucker, the aphis, and scab 

 could hardly have been worse than they have been where this spray has 

 been used, while infestation by caterpillars has been slight, the Coldin moth 

 larva being "conspicuous by its absence." It does not follow that the caustic 

 spraying has been the cause of this immunity. In the New York State 

 experiments the lime, sulphur, and caustic soda mixture was of no effect as a 

 preventive to the Codlin moth. For that purpose it was followed by two spray- 

 ings with Bordeaux-arsenical mixtures. 



It is obvious that the spraying of fruit trees and bushes is at present in 

 a crudely empirical stage, and that a great number of experiments more varied 

 and precise than those which have been carried out hitherto require to be 

 conducted before the practice will be placed upon a satisfactory basis. There 

 is much to be learned as to the best insecticides and fungicides, the most 

 effective strength of each compatible with safety in application to different 

 fruits, the suitability of various materials for mixing, and the most appropriate 

 seasons for operations desirable for various purposes. — W. E. Bear in the Journal 

 of the Board of Agriculture. 



