(a) No person who owns, leases, or operates a ditch, canal, or reservoir or who cultivates land abutting a reservoir, ditch, flume, canal, wasteway, or lateral may permit Johnson grass or Russian thistle to go to seed on the waterway within 10 feet of the high-water line if the waterway crosses or lies on the land owned or controlled by him.
(b) The provisions of this section are not applicable in Tom Green, Sterling, Irion, Schleicher, McCullough, Brewster, Menard, Maverick, Kinney, Val Verde, and San Saba counties.