224 PRACTICAL TREE REPAIR 



ing its sap and deforming its growth. Slit the 

 bark of the calluses. 



This last direction may require some explana- 

 tion. In the second chapter, dealing with the 

 nature of the growth of trees and the way in which 

 wounds are healed, it was brought out that growth 



Callus slit along the dotted 

 lines to accelerate its 

 growth 



normally proceeds fastest where bark pressure is 

 least. It is that very fact which explains) the 

 growth of a callus. At first the callus grows very 

 rapidly, but as the bark covering it gets thicker, 

 growth becomes slower and slower. Finally, the 

 callus may become " bark-bound," just as a tree 

 sometimes does. As it relieves a bark-bound tree 



