Wyo. Stat. § 37-9-301: Fireguards.

It shall be the duty of every railroad corporation operating its line of road, or any part of it, within this state, upon its right-of-way upon each side of its roadbed, to maintain annually an effective fireguard upon order of and satisfactory to specifications set forth by the department of transportation so as to prevent fire from spreading to lands adjacent to the right-of-way. The fireguards need not be maintained within the limits of any city or town, nor along that portion of the line of a railroad where the desert or mountainous character of the adjoining land would render such burning impractical or unnecessary.