I checked on this and, of course, that led to several different opinions.
What I got from looking at this was to consult an arborist to determine the value of trees and if it seems worth it, to get a lawyer who specializes in law about trees (I didn't realize that there were lawyers who specialized in this).
As to the IRS rules (that are subject to change at any time), you'll need to go to their website or call them.
Sorry I could not provide a direct link at this time. My apologies.
I won't be back to where the papers are until spring so not much I can do until I get back. --75.7.xx.xx