boughndary-line
A dividing-perimeter between properties formed by a row of trees.
Even though re-locating surveyor's posts is a serious offense, it is still done quite often. Having your properly marked by a boughndary-line, therefore, is a much more "permanent" solution, since it is a lot harder to move --- one would need to actually dig up the deeply-rooted trees and transport said weighty timber-hulks to another location.