Iowa Code § 327G.5: Hog-tight fences.

When any person owning land abutting on the right-of-way is maintaining a hog-tight fence on all sides thereof or any division of such land except along such right-of-way, the railway company owning such right-of-way shall, on written request of the landowner, make such right-of-way fence along such enclosed land hog-tight by the addition of barbed or woven wire or other equally efficient means.