Any county which has established an agricultural commodity research district may contract under the provisions of chapter 70 with any other county which has also established such a district to carry out common functions or to form a joint district. If a joint district is formed, it shall be governed by a joint board of supervisors comprised of two members of each board of supervisors of each participating county elected by the board of supervisors of the agricultural research district of that county. The contract creating the joint district shall specify the procedures for the election of the joint board and the terms of office of the members of the joint board. The joint board shall exercise such powers as may be designated by the contract creating the joint district, including the awarding of grants and cooperation with any other county agricultural commodity district or joint district or with any college or university or governmental unit to exercise any of the powers granted pursuant to the provisions of sections 67.1230 to 67.1253 to the participating county agricultural commodity districts comprising the joint district.