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TREES AS GOOD CITIZENS 



removed. To leave decayed or diseased tissue will spoil 

 the whole job. 



Repair begins by digging out the diseased or decayed 

 wood. For this purpose the operator should be equipped 

 with a knife, gouge, chisels and mallet. He should not be 

 alarmed at the growth of the cavity brought about by his 



How a cavity is caused and how to treat it. 



a. Stub left after pruning. 



b. Decay starting in stub. 



c. Decay well advanced. 



d. Cavity formed in trunk. 



e. Section of trunk showing cavity. 



f . Cavity cleaned out and ready for closing. 



digging, for it is necessary to remove the affected tissue, 

 no matter how large the resulting hole may become. To 

 make sure that the last trace of decay or disease is taken 

 out, the digging should extend into healthy wood. On 

 the outside, the rolls of bark which have grown up at the 

 edges of the cavity should be pared off to a point even with 

 the natural shape of the trunk. 



When the cavity has been cleaned, exposing a smooth 

 surface of sound wood at all points, the cambium and 

 adjacent parts should be painted with shellac; then the 

 walls should be sterilized with copper sulphate or creosote 

 applied with a brush. This should be followed by at least 



