In this chapter:
(1) "Agency" means any department, agency, board, commission, committee, council, officer, subdivision or instrumentality, corporate or otherwise, of this state.
(2) "Board" means the land and water conservation board created under s. 15.135 (4) .
(3) "Department" means the department of agriculture, trade and consumer protection.
(4) "Landowner" means any person over 18 years of age and any partnership, limited liability company, firm or corporation that holds title to land lying within a county whether or not this land is subject to easement, mortgage, lien, lease or restrictive covenant, except that this term does not include any person who is under guardianship, a person who is incompetent or a person who is mentally ill. A person, partnership, limited liability company, firm or corporation is deemed to hold title to land if the person, partnership, limited liability company, firm or corporation has any of the following:
(a) Title as sole owner.
(b) Title as a joint owner.
(c) Title as owner of an undivided interest.
(d) Title as sole or joint trustee or as sole or joint assignee.
(e) A land contract vendee's interest therein.
(5) "Land user" means any person who uses land as an operator, lessor or renter.
(6) "Secretary" means the secretary of the department.