25 



readily. The scars are formed by the spores of the fungous en- 

 terlng through a woi;4d In the bark. They seem unable to pene- 

 trate through living barkjto the cambium, but as above stated 

 must have a passage made for them. This fact is suggestive of 

 preventive measures. In regions where canker is prevelent the 

 utmost care must be exercised to avoid wounding the bark. Often 

 wounds are iwade by the pickers in scraping their ladders against 

 the limbs, or by the cultivators or plows barking the trunk 

 during the cultivating operations. All such accidents are to be 

 strictly avoided if this disease is to be successfully prevented. 

 Often cankers can be cured (if they have not completely girdled 

 the limbs, in which case the limb should be removed) by cutting 



ate. 



off the diseased area until clean wood and bark fe reached, and 

 painting the woutid with white lead to which a little lamp-black 

 has been added just as in pruning. Paddock recommends painting 

 the v/ou^d with the following wash. 



"hale oil soap 1 part. 



Slaked lime 2 parts. 



-ater 4 gallons. 



"Tood ashes to thicken as desired. 

 Dissolve the soap in hot water, then stir in the lime. 

 T'hen the ingredients have been reduced to a smooth state by 

 stirring, dilute v/ith water to 4 gallons, then stir in the wood 

 ashes until the wash is of the desired consistancy. 

 Fire Blight. 

 This is a bacterial disease caused by Bacillus amylovAreb^s . 

 It is a ^i;^ease to which young trees betv/een the ages of eight 



.^^ fifteen years of age are especialljr susceptible. It occurs, 

 hov/eyer, on older trees and is often the cause of their death. 

 Many parts of the tree are affected by it, and its extensive 



