After the filing and recording of the order with the officers under s. 77.02 (3) the lands described therein shall be “Forest Croplands”, on which taxes shall thereafter be payable only as provided under this subchapter. The enactment of ss. 77.01 to 77.14, petition by the owner and the making of the order under s. 77.02 (3) or (4) (a) shall constitute a contract between the state and the owner, running with the lands, for a period of 25 or 50 years at the election of the applicant at the time the petition is filed, unless withdrawn under s. 77.10, with privilege of renewal by mutual agreement between the owner and the state, whereby the state as an inducement to owners and prospective purchasers of forest croplands to come under ss. 77.01 to 77.14 agrees that, unless withdrawn under s. 77.10, no change in or repeal of ss. 77.01 to 77.14 shall apply to any land then accepted as forest croplands, except as the department of natural resources and the owner may expressly agree in writing and except as provided in s. 77.17. If at the end of the contract period the land is not designated as managed forest land under subch. VI, the merchantable timber on the land shall be estimated by an estimator jointly agreed upon by the department of natural resources and the owner, and if the department and the owner fail to agree on an estimator, the judge of the circuit court of the district in which the lands lie shall appoint a qualified forester, whose estimate shall be final, and the cost thereof shall be borne jointly by the department of natural resources and the owner; and the 10 percent severance tax paid on the stumpage thereon in the same manner as if the stumpage had been cut. The owners by such contract consent that the public may hunt and fish on the lands, subject to such rules as the department of natural resources prescribes regulating hunting and fishing.