TREATMENT WITHOUT FILLING 195 



made as unfavorable as possible for the growth 

 of fungi and the oxidation of wood. There are 

 several ways in which to go about the application 

 of this principle. The first step is to remove all 

 loose decayed wood, and to impregnate the re- 

 mainder with a moisture-repelling preservative 

 such as hot carbolineum. In order to do this 

 effectively, it is usually necessary to let the cavity 

 dry for a few days, or else to char it out with a 

 gasoline torch. If the carbolineum is brushed 

 on it must be dashed into all the cracks. At least 

 one coat should be sprayed on, if possible. The 

 first thing to be attended to, however, is the drain- 

 age of the cavity, if it needs draining. An in- 

 cision can be made to accomplish this, or, if there 

 is a " pot " to handle, the decayed wood in it can 

 be cut and burned out, and it can be filled with 

 stones and asphalt. 



If a hole runs up the tree it should be cleaned 

 out as well as possible, sprayed with carbolineum, 

 and blocked up in some way. An old sack, or a 

 sack full of excelsior or straw, the whole thing 

 dipped in carbolineum, might fill the bill. 



If a cavity so treated is located in such a way 

 that the rain cannot beat into it there need be no 

 covering over the mouth to keep out the weather. 

 Indeed, light and ventilation are likely to retard 

 the growth of the fungus. If the mouth is hori- 

 zontal, on the other hand, it may be well to tin 



