36 CFR § 261.12 - National Forest System roads and trails.
The following are prohibited:
(a) Violating the load, weight, height, length, or width limitations prescribed by State law except by special-use authorization or written agreement or by order issued under § 261.54 of this Chapter.
(b) Failing to have a vehicle weighed at a Forest Service weighing station, if required by a sign.
(c) Damaging and leaving in a damaged condition any such road, trail, or segment thereof.
(d) Blocking, restricting, or otherwise interfering with the use of a road, trail, or gate.
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