Neb. Rev. Stat. § 60-3,214

No registration shall be required for snowmobiles: (1) Owned and used by the United States, another state, or a political subdivision thereof; (2) Registered in a country other than the United States and temporarily used within this state; (3) Covered by a valid license of another state and which have not been within this state for more than thirty consecutive days; and (4) Which are operated only on land owned or leased by the owner thereof.