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cut off of crops stricken by disease. This is a practice 

 which can rarely effect much good. The leaves are the 

 manufactory of the plant on which all developments 

 are dependent. If these are destroyed the tubers must 

 cease to grow, and as by far the larger amount of 

 growth of tubers takes place during the few weeks the 

 plants are dying down, little good can be done by 

 destroying them when growing. There is some reason 

 in doing it if the crop has approached maturity, and 

 the tubers have reached a fair size. The cutting down 

 of the haulm has sometimes been done with advantage 

 late in the autumn, not with the view of checking 

 disease, but to kill the crop, so that the skin of the 

 tubers may harden sufficiently to permit of their being 

 dug before severe frost sets in and destroys them. 

 This, of course, can only be done profitably when the 

 tubers are well developed. 



pressing with Bouillie Bordelaise to prevent 

 Disease. 



Spraying with Bouillie Bordelaise (or the Bordeaux 

 Mixture), or a solution of sulphate of copper and lime, 

 applied to the leaves of potato plants to cheek the 

 disease known as Phytophthora infestans, is one of 

 the most striking practices introduced to agriculture 

 during the past few years. The possibility of holding 

 the disease in check by any such means, or by any 

 treatment of the growing plant, was looked upon ten 

 years ago as an impossibility, and though the fact that 

 it is now possible is firmly established, there are still 



