Blight Canker of the Apple Tree. 



201 



The planting of varieties known to be more or less resistant to this 

 disease is to be recommended. The Wolf River and Talman Sweet appear 

 to be of this sort, wdiile Baldwin and Ben Davis suffer most severely. 

 Desirable non-resistant varieties may be top grafted on resistant stocks. 



Mr. M. B. Wait, in a lecture at Lockport, N. Y., January 3, 1906, 

 before the New York State Fruit Growers' Association, recommended the 

 spraying of pear trees early in the spring with the Lime-Sulphur wash as 



Fig. 78. — Canker formed about 

 the moii'.h of the burrow of a 

 borer near base of an apple tree. 



Fig. 79. — Pruned stub canker, with diseased 

 hark and stub removed, treated with corrosive 

 sublimate a)id painted over. This is the 

 same canker as Fig. 75, after treatment. 



a means of covering up " hold over " cankers of the fire blight that had 

 been overlooked in the " cutting out process." This treatment serves only 

 to destroy any bacteria that may exude from trees already diseased, and 

 thus prevent the cankers from serving as sources of infection. It will 

 not protect healthy trees from infection. A similar treatment of can- 

 kered apple trees would certainly be of value. 



