Authority is hereby given for the conservation commission to enter into cooperative agreements with such federal agencies as have or may be given such authority by act of congress for the purpose of acquisition, management, and operation of public forest lands. Under such cooperative agreements, forest lands purchased by the United States shall be administered by the conservation commission as state forest lands and, during the period the agreement remains in force, 1/2 of the gross proceeds from all lands covered by the agreement and to which the United States holds title shall be paid by the state to the United States: Provided, That when the amount of such payments shall equal the total sum expended by the United States in acquiring said lands, title to said lands shall be transferred from the federal government to the state: And provided further, That in the event of the termination of said cooperative agreements where the title to said lands is in the United States, then the federal government shall reimburse the state for so much of the state funds as have been expended in the administration, development, and management of the lands involved as the secretary of agriculture may decide to be fair and equitable.