tree hollow or tree hole is a semi-enclosed cavity which has naturally

tree hollow tree hole semi-enclosed cavity naturally formed trunk branch found old trees cut quality safety albs animal arboretum arborist background badger bark black branch brown cavity circle closeup dendrobium orchid environment fall forest gardening green hole hollow house insect lawn lumber material natural nature nest old outdoor outdoors park pattern pipe plant playground rough round salix shelter stability texture tree trunk willow wood wooden yard