138 



TREES IN WINTER 



other cases the trees are injured by horses or passing vehicles. 

 Wounds made from any such causes may be easily and quickly 

 healed if treated before the wound has had a chance to dry out. 

 They should have their edges trimmed up with a sharp knife, 

 always cutting back to firm bark. The whole surface should then 

 be covered with grafting wax and bandaged with cloth. If done 

 in the early part of the summer a new bark will develop over the 

 whole surface. This method of healing is different from that 

 associated with old wounds. 



Where a portion of the bark has been removed all around the 

 trunk, the trouble is more serious, but if the wound is not more than 

 three or four inches in width and if the injury occurred in the early 

 part of the summer when the cambium is active, the tree may be 

 saved by protecting the wound with wax as just described. If the 

 wound has become somewhat dried, or if it is a wide one, it will 

 be necessary to resort to bridge-grafting. 



For "bridging" a wound it is necessary to smoothly cut back the 

 edges of the wound to sound bark and connect the two edges with 

 freshly-cut scions. The scions should be of the past season's growth 



Fig-. 62. Bridge Grafting. A process used in healing over wounds 

 that extend clear around the trunk or a large branch. 



