DRESSINGS FOR WOUNDS 113 



the application of coal-tar. This is not the case, 

 however, with pome -bearing trees (apples, pears, 

 etc.); to these coal-tar may be applied with per- 

 fect safety." Card reports* that in experiments 

 in Nebraska "coal-tar seems to have been a posi- 

 tive hindrance to the healing process, not one 

 wound having been reported as healing extremely 

 well." It is not said, however, whether the tar 

 injured the tissues, or whether the apparent re- 

 sults may not have been due to the position and 

 character of the wound quite as much as to the 

 dressing. In my own experiments, which I have 

 already reported (pages 104 to 109), tar did no 

 damage. In fact, the rapid -healing wound bbb, 

 Fig. 90, was dressed with tar. In those experi- 

 ments, paint, grafting -wax, linseed oil and tallow 

 were also used, but all the differences in the 

 healing of the wounds were evidently the result 

 of other conditions than the dressings. I will 

 expand my affirmation on page 109 to read: The 

 position of the wound on the tree and the nature 

 of the cut exert more influence in determining 

 the healing than either the season in which the 

 wound is made, or the kind of dressing which it 

 receives. 



My conclusion is, after having had the question 

 in mind for a decade, that a heavy application of 

 lead paint is the best all-round dressing for com- 



"Notes on Pruning, Bull. 50, Nebraska Experiment Station. 

 H 



