One day last July, I stopped over lunch at Houghton’s Pond in the Blue Hills Reservation outside Boston to let Musti and Luc stretch their legs and pee on trees for a few minutes.  As we were walking, I saw an oddly damaged white oak tree. As we got closer, I realized that someone had gone at it with a chainsaw, attempting to cut off a large burl from the base of the trunk. Late last year, a number of stories in the local media suggested  that the illicit removal of burls from public trees was becoming  an epidemic.  The Boston Globe described a chainsaw-wielding thief cutting burls off trees in the Fenway Victory Gardens, and another story described similar vandalism in Mount Auburn Cemetery.  In…