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has the additional misfortune of attracting lumbermen and nut- 

 gatherers. If it escapes winter injuries to its trunk, the spring 

 storms are sure to break the smaller branches and abrade the 

 surfaces of the larger limbs ; if it is not disfigured by the green 

 fly and twig-borer during summer, it is sure to be mutilated by 



savage hordes of small boys in autumn. Even the ubiquitous 

 squirrel may spread the disease with tooth and claw while cutting 

 off ripe burs and racing up and down the trunks ; while every 

 bird and insect that rests upon an infected spot is liable to carry 

 the spores upon its feet or body to other trees. Mice, voles and 

 rabbits often make wounds about the base of a tree and carry the 

 spores in their fur. All during the growing season spores are 

 being developed in countless numbers, and these are liable to fall 

 into even the slightest abrasions of the bark and germinate. 



The treatment of a disease of this nature must, of course, be 

 almost entirely preventive. When once allowed to enter, it 

 cannot be reached by poisons applied externally, nor can the 

 spores, which issue continuously and abundantly through erup- 



