While conducting our urban forest inventories we noted that often urban trees occurred not because they were planted and cared for but rather because an area was ignored long enough for a tree to become established. The most striking evidence of this were the trees (some of considerable size) that we encountered growing into and through old fences and posts. Unfortunately, the trees established in these unlikely places were more likely to be non-native, ‘weedy’ species, such as Tree of Heaven, Norway maples, Manitoba maples and locusts. We snapped these photos of trees engulfing a fence along a property boundary. Trees along fence lines should be cut before they reach this size.