of 



spend more than three days upon one tree- 

 trunk ; this he pecked full of holes and from its 

 vitals he dragged more than a gross of devour- 

 ing grubs. In this case not only was the beetle 

 colony destroyed but the tree survived. 



Woodpecker holes commonly are shallow, 

 except in dead trees. Most of the burrowing or 

 boring insects which infest living trees work in 

 the outermost sapwood, just beneath the bark, 

 or in the inner bark. Hence the doctor does not 

 need to cut deeply. In most cases his peckings 

 in the wood are so shallow that no scar or re- 

 cord is found. Hence a tree might be operated 

 on by him a dozen times in a season, and still 

 not show a scar when split or sawed into pieces. 

 Most of his peckings simply penetrate the bark, 

 and on living trees this epidermis scales off; thus 

 in a short time all traces of his feast-getting are 

 obliterated. I have, however, in dissecting and 

 studying fallen trees, found a number of deep 

 holes in their trunks which woodpeckers had 

 made years before the trees came to their death. 

 In one instance, as I have related in "The Story 

 of a Thousand-Year Pine" in "Wild Life on the 



198 



