CA Gov't Code Section 66606.6

Nothing in this title shall deny the right of private property owners and local governments to establish agricultural preserves and enter into contracts pursuant to the provisions of the California Land Conservation Act of 1965. The commission, within six months after the effective date of this section, shall institute an affirmative action program to encourage local governments to enter into contracts under the California Land Conservation Act of 1965 with owners of property to which the provisions of that act may be applicable.