CHAPTER XVIII 

 PRACTICAL TREE SURGERY* 



287. Object of tree surgery. It is well known that trees are sub- 

 ject to all sorts of injuries, from sources too numerous to mention. 

 In a great majority of cases these injuries are allowed to remain 

 untreated often for years. Rot-producing fungi commonly gain 

 entrance at these places, and eventually the original inconspicuous 

 or unobserved injury develops into a comparatively large area of 

 decay. The real aim of tree surgery is to repair the damage re- 

 sulting from such neglected injuries and rotted areas. 



288. Principles involved. In most tree-surgery work a few funda- 

 mental principles must be observed to secure good results. These 

 may be summarized as follows: (1) Remove all decayed, diseased 

 or injured wood and bark. When on small limbs, this can often 

 best be done by removing the limb. On larger limbs or on the trunk 

 it may at times mean the digging out of a cavity. (2) Sterilize all 

 cut surfaces. (3) Waterproof all cut surfaces. (4) Leave the 

 work in the most favorable condition for rapid healing. This will 

 often mean the filling of deep cavities. (5) Watch the work from 

 year to year for defects. If any appear, attend to them immediately. 



289. Qualifications of workmen. Tree surgery, or, more properly, 

 as some interested persons would have tree owners believe, tree re- 

 pair work, is not a mysterious art known to only a favored few who 

 alone are fitted to undertake it. It can be undertaken by any care- 

 ful rtian who has a good general knowledge of the structure and life 

 history of a tree, its normal manner of covering wounds and how 

 insects and decay organisms cause damage, provided he can handle 

 the necessary tools and will apply in a practical manner his knowl- 

 edge of the anatomy of a tree, together with a generous admixture 

 of good common sense. 



290. Types and scope of work. I n its simplest type, tree surgery 

 consists in removing dead or decayed limbs or stubs from a tree 

 and treating the scar with an antiseptic and waterproof covering to 

 prevent decay while healing. Another type consists in cutting out 

 the decayed and diseased matter in trees and filling the cavities with 

 cement or other materials to facilitate the normal healing-over 

 process. This is often referred to as "tree dentistry." a term which 

 very aptly indicates the character of the work. Filled cavities do 



* Paragraphs 287 to 311 have been excerpted and slightly condensed from J. T. 

 Collins's article in the United States Department of Agriculture Year Book, 1913, 

 Pages 162 to 190. Only about half the article is herewith included, because the 

 balance deals mostly with physiological and other features already discussed in 

 this volume. 



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