Mont. Code Ann. § 80-12-211

A landowner who sells land consisting of 80 acres or more to a beginning farmer at 9% or less interest on a long-term contract is entitled to a reduction in the landowner's taxable income in an amount equal to 100% of any income or capital gain, or both, realized and otherwise subject to state income taxes from the sale, up to a maximum of $50,000, if the transaction is approved by the authority for this purpose.