25 CFR §162.105

1. (a)An agricultural lease negotiated by Indian landowners may cover more than one tract of Indian land, but the minimum consent requirements for leases granted by Indian landowners under subparts B through D of this part will apply to each tract separately. We may combine multiple tracts into a unit for leases negotiated or advertised by us, if we determine that unitization is in the Indian landowners' best interests and consistent with the efficient administration of the land.
2. (b)Unless otherwise provided in the agricultural lease, the rent or other consideration derived from a unitized agricultural lease will be distributed based on the size of each landowner's interest in proportion to the acreage within the entire unit.