The Care of Trees 



143 



FIG. 94. Supporting a tree 

 at the fork. 



bark of the tree, but stops at a depth equal to the thick- 

 ness of the bark so that the healing callus may overgrow 

 the filling. Filling a large cavity 

 in the trunk tends to prevent the 

 tree from being blown over by the 

 wind. The removal of dead wood 

 before the cavity is filled and the 

 exclusion of water by the filling 

 tend to prevent further decay. 

 Cavities caused by decay in the 

 trunk where a big limb has broken 

 off from it or has been improperly 

 pruned are treated like hollows at 

 the base of the trunk, to arrest 

 the spreading of the disease. 



Tree doctors also fasten together with chains or rods 

 large limbs that are in danger of splitting apart, fasten- 

 ing the ends of the chains, not to bands, which would in 

 time cut through the bark and into the wood, but to 

 bolts passed through the branches after boring holes 

 through them. Tree surgery requires judgment and skill, 

 and the owner of trees needing repair must be cautious 

 to avoid employing an impostor, who will do more harm 

 than good. If the injury that calls for attention is 

 merely abrasion of the bark, the owner of the tree should 

 cut away with a sharp knife all loose, ragged, or injured 

 bark as far as the injury extends. If left on the tree, 

 this bark would shelter insects and fungus spores 

 which in time would injure the tree. The exposed wood, 

 unless its area is small, should be painted with refined 

 gas tar. 



