1. An owner of farmland may submit a proposal to the county board for the creation or expansion of an agricultural area within the county. An agricultural area, at its creation, shall include at least three hundred acres of farmland; however, a smaller area may be created if the farmland is adjacent to farmland subject to an agricultural land preservation ordinance pursuant to section 335.27 or adjacent to land located within an existing agricultural area. The proposal shall include a description of the proposed area to be created or expanded, including its boundaries. The territory shall be as compact and as nearly adjacent as feasible. Land shall not be included in an agricultural area without the consent of the owner. Agricultural areas shall not exist within the corporate limits of a city. The county board may consult with the department of natural resources when creating or expanding an agricultural area contiguous to a location which is under the direct supervision of the department, including a state park, state preserve, state recreation area, or sovereign lake. Agricultural areas may be created in a county which has adopted zoning ordinances. Except as provided in this section, the use of the land in agricultural areas is limited to farm operations.
 2. The following shall be permitted in an agricultural area:

 a. Residences constructed for occupation by a person engaged in farming or in a family farm operation. Nonconforming preexisting residences may be continued in residential use.
 b. Property of a telephone company, city utility as defined in section 390.1, public utility as defined in section 476.1, or pipeline company as defined in section 479.2.
 3. The county board of supervisors may permit any use not listed in subsection 2 in an agricultural area only if it finds all of the following:

 a. The use is not inconsistent with the purposes set forth in section 352.1.
 b. The use does not interfere seriously with farm operations within the area.
 c. The use does not materially alter the stability of the overall land use pattern in the area.