u/ArmadilloMajor7386

Does anyone know the laws/rules regarding non-motorized bike usage on forest service land? I know an area in Montana with a ton of old fire/logging roads that I want to ride. They are unmarked, which means no motorized use for sure. It would basically be treated as being off-trail riding, or forest-gliding as I call it. Is this legal to do on a normal mtb?