Hi My enclosed run sits primarily under the canopy of my large holly tree. A tree I am very fond of. It's about 60' tall. Will my chickens kill or harm it, either by scratching the roots too much, or more likely, by the "hot" fertilizer they spread around? I have wood chips down as bedding in the run, about 4" deep. Anyone have a similar situation? I'm in PA. Thanks for your help.