2009 Iowa Code
Title 8 - Transportation
Subtitle 1 - Highways and Waterways
CHAPTER 314 - ADMINISTRATIVE PROVISIONS FOR HIGHWAYS
314.17 - MOWING ON INTERSTATES AND PRIMARY HIGHWAYS.

        314.17  MOWING ON INTERSTATES AND PRIMARY HIGHWAYS.
         On or after January 1, 2003, the department shall not mow roadside
      vegetation on the rights-of-way or medians on any primary or
      interstate highway.  Mowing shall be permitted as follows:
         1.  On rights-of-way which include drainage ditch areas.
         2.  On rights-of-way within three miles of the corporate limits of
      a city.
         3.  To promote native species of vegetation or other long- lived
      and adaptable vegetation.
         4.  For establishing control of damaging insect populations,
      noxious weeds, and invader plant species.
         5.  For visibility and safety reasons.  

         98 Acts, ch 1212, §7