Neb. Rev. Stat. § 60-6,334

The Game and Parks Commission shall establish rules and regulations for: (1) The operation of snowmobiles upon designated state-controlled or state-operated lakes within the State of Nebraska during the period of time when the lake is frozen and safe for the use of snowmobiles; and (2) The operation of snowmobiles on established snowmobile courses or trails within public parks or on public land in this state owned or leased by the state.