CHAPTER XIII 



PRESERVATIVES AND MATERIALS 



Coal-Tar . For covering tree wounds, coal- 

 tar, a waste product of gas-works, is perhaps 

 preferable to any other preparation. Coal- 

 tar can be used either on living or dead wood 

 with equally good results, forming an imper- 

 vious coating that is proof against dampness 

 as well as insect and fungus attacks. The 

 odour is objectionable to all forms of insect 

 life, and effectually wards off their attacks. It 

 is readily applied with a long-handled painter's 

 brush, and should be rubbed well into the 

 diseased or wounded parts of the tree. 

 Usually it is applied cold, but when pruning 

 is being carried out in wintry weather, a 

 slight warming so as to thin the tar may be 

 necessary before it is painted on the wood. 



A single coating, if well rubbed in, will last 



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