Some trees just don’t know when to quit.   I have admired the tenacity of trees growing on rock cliffs and the walls of buildings.  We sometimes camp beside one that leans far out over a creek that undercut the bank that supported that side of the root system.  Tender new roots probe into the tiniest cracks then slowly bulk up to cleave rock and crumble cement.  Even metal pipes are no match for thirsty roots.  We can’t beat them, and the world will work way better if we join them already.  Sign me: Tree Hugger.