(a) After June 8, 1971, no advertising device shall be erected or maintained:
(1) which purports to be or resembles an official traffic-control device, sign, or signal, or railroad sign or signal; or which hides from view or interferes in any material degree with the effectiveness of any traffic-control device, sign, or signal, or railroad sign or signal, or which obstructs or interferes with the driver's view of approaching, merging, or intersecting traffic for a distance not to exceed 500 feet;
(2) which prominently displays the word "stop" or "danger";
(3) which contains statements, words, or pictures of an obscene, indecent, or immoral character, or such as would offend public morals or decency;
(4) on any right-of-way of the interstate system of highways, except as otherwise provided by law or allowed by the commissioner;
(5) on private land without the consent of the owner or occupant thereof;
(6) on trees, shrubs, or which are painted or drawn upon rocks or natural features, or on public utility poles;
(7) which has distracting flashing or moving lights so designed or lighted as to be a traffic hazard;
(8) to which access can be obtained only from an interstate main-traveled way but excluding frontage roads adjacent thereto;
(9) which are structurally unsafe, are in disrepair, or are abandoned.
(b) The prohibition under paragraph (a), clause (7), does not include an electronic advertising device that changes displayed digital content no more frequently than once every six seconds.