25 CFR 167.4: Regulations; scope; exceptions.

The grazing regulations in this part apply to all lands within the boundaries of the Navajo Reservation held in trust by the United States for the Navajo Tribe and all the trust lands hereafter added to the Navajo Reservation. The regulations in this part do not apply to any of the area described in the Executive order of December 16, 1882, to individually owned allotted lands within the Navajo Reservation nor to tribal purchases, allotted or privately owned Navajo Indian lands outside the exterior boundaries of the Navajo Reservation.