After National Forest System roads, National Forest System trails, and areas on National Forest System lands have been designated for over-snow vehicle use pursuant to 36 CFR 212.81 on an administrative unit or a Ranger District of the National Forest System, and these designations have been identified on an over-snow vehicle use map, it is prohibited to possess or operate an over-snow vehicle on National Forest System lands in that administrative unit or Ranger District other than in accordance with those designations, provided that the following vehicles and uses are exempted from this prohibition:
36 C.F.R. §261.14