1. The commission may adopt rules to regulate or prohibit outdoor advertising in order to preserve scenic corridors adjacent to, and visible from, roads and highways designated as scenic byways pursuant to the provisions of section 226.797, except, that on-premise signs may be regulated, but not prohibited. Areas zoned commercial or industrial shall not be designated as scenic byways.

2. The commission may adopt rules to implement a program for the erection and maintenance of tourist-oriented directional signs within the right-of-way of scenic byways in the state. The tourist-oriented directional signs shall provide business identification and directional information for businesses, services, natural attractions and activities which, during a normal business season, derive the major portion of the income and visitors for the business or activity from motorists not residing in the immediate area of the business or activity. Tourist-oriented directional signs shall only be used on roads and highways designated as scenic byways under section 226.797.