The state lands are classified as follows:
(1) Class 1--lands which are principally valuable for grazing purposes;
(2) Class 2--lands which are principally valuable for the timber that is on them or for the growing of timber or for watershed protection;
(3) Class 3--lands which are principally valuable for the production of crops;
(4) Class 4--lands which are principally valuable for uses other than grazing, crop production, timber production, or watershed protection.