Oregon Revised Statutes Highways, Roads, Bridges and Ferries § 376.360

In the event the forest road contractor is authorized by the provisions of the contract to operate vehicles or combinations of vehicles, including any load thereon, of any size or description not otherwise authorized by law, the county court shall erect and maintain signs giving notice thereof in a conspicuous manner and placed at each end of the forest road or section of forest road covered by the contract, and at such other places as may be necessary to inform and warn the public.