442.591.  Exceptions. — The restrictions set forth in sections 442.560 to 442.592 shall not apply to agricultural land or any interest therein acquired by an alien or foreign business for immediate or potential use in nonfarming purposes.  An alien or foreign business may hold such agricultural land in such acreage as may be necessary to its nonfarm business operation; provided, however, that pending the development of agricultural land for nonfarm purposes, such land may not be used for farming except under lease to a family farm unit; a family farm corporation defined in section 350.010; an alien or foreign business which has filed with the director under sections 442.560 to 442.592; or except when controlled through ownership, options, leaseholds or other agreements by a corporation which has entered into an agreement with the United States of America pursuant to the New Community Act of 1968 (Title IV of the Housing and Urban Development Act of 1969, 42 U.S.C. 3901-3914), as amended, or a subsidiary or assignee of such a corporation.