i8 TREE WOUNDS AND DISEASES 



if unattended to, disease would be carried direct 

 into the main trunk. Perhaps old elm trees 

 suffer most in this way, owing to the brittle 

 nature of the wood, which causes it to snap 

 readily, and also to the fact that this tree is 

 more apt to be affected by disease and heart- 

 rot than most other species. Not only are the 

 branches readily broken over by the wind, but 

 what is known as branch-shedding often takes 

 place during still, hot weather, and without 

 the slightest warning. 



The point at which a branch has been 

 broken over should be made quite smooth, first 

 by aid of a saw, and afterwards by the pruning 

 knife or chisel, care being taken that the 

 bark around the wound is neither injured nor 

 loosened, and that it comes close up to the saw 

 mark. A coat of paint or, preferably, coal- 

 tar may then be applied, both pruning and 

 dressing being carried out during dry weather. 

 A broken branch or tree stem should never 

 be sawn over on the horizontal, but always in 

 a sloping direction, so that water may pass off 

 rapidly. When, from accident or otherwise, 

 the stem of a tree requires to be sawn over, 



