SHADE TREES. 



201 



There are many symptoms characteristic of* this root injury which 

 manifest themselves according to the extent and nature of the injury. If 

 the entire root system is killed the tree dies rather quickly. Sometimes 

 an effort will be made on the part of the tree during the spring, especially 

 if a few roots are still alive, to produce foliage, but the tree soon dies. 

 Then, again, a tree will mature its foliage fairlj^ well, but as soon as the 



Fig. 72.— Elm slowly dyins from defective root system. 



soil becomes slightly dry it will die. In such cases the leaves often tiu^n 

 brown and dry up, and remain on the tree in this condition. There are 

 many cases in which the root systems are only slightly affected, when 

 the tree may live for some time and only show a defective top. This 

 slight affection of the root system is particularly common in red maples, 

 which very often recover in a year or two, the only apparent effect being 

 the somewhat smaller leaves found at the tree's crown. In more severe 



