Cal. Pub. Res. Code § 4552

The rules and regulations adopted by the board shall be based upon a study of the factors that significantly affect the present and future condition of timberlands and shall be used as standards by persons preparing timber harvesting plans. In those instances in which the board intends the director to exercise professional judgment in applying any rule, regulation, or provision of this chapter, the board shall include in its rules standards to guide the actions of the director, and the director shall conform to such standards, consistent with Section 710.