This chapter shall not be applied to bar any lessor or lessor’s successor as a reversioner of the lessor’s right to possession on the expiration of any lease; or to bar or extinguish any easement or interest in the nature of an easement, the existence of which is apparent from or can be proved by physical evidence of its use; or to bar any right, title or interest of the United States, by reason of failure to file the notice herein required. [C71, 73, 75, 77, 79, 81, §614.36 ] 2004 Acts, ch 1052, §7 Referred to in §257B.28 , 455I.9 , 457A.2 , 614.32