82 PRACTICAL TREE REPAIR 



around its throat. The gills are white. The 

 honey mushroom produces growths sometimes 

 called " shoe strings " which are commonly seen 

 under the rotten bark of dead stumps, and in the 

 surrounding soil. They are flat (in open soil 

 round) black strands of hard-woven mycelium. 

 It is at the ends of them that the mushrooms are 

 found. The fungus enters through a wounded 

 root, spreading into and killing the cambium, and 

 progressing from root to root by means of the 

 " shoe strings." When most of the roots have 

 been killed up to the trunk the tree suddenly blows 

 over. The rotten roots should be dug out if pos- 

 sible, and no new tree should be planted near by 

 for several years. 



In addition to these fungi which cause disease 

 in living trees, there are two found only on dead 

 trees or branches which are so common that they 

 must at least be referred to. One is Fomes ap- 

 planatus, the common brown and white shelf- 

 fungus. It is found only on dead trees or dead 

 parts of trees. The other is Polystictus versi- 

 color, the variously tinted and striped papery little 

 shelf-like sporophores of which are omnipresent 

 in the woods and along the railroad track. It 

 attacks but one tree in the living state the 

 catalpa. 



Below wounds and in the vicinity of cracks in 

 elm, maple, and horsechestnut trees there is often 



