California Code, Public Resources Code - PRC § 4597.15

Notwithstanding any other provisions of this chapter, if a registered professional forester certifies by written declaration, on behalf of the timber owner or operator, that the working forest harvest notice conforms to and meets the requirements of the approved working forest management plan under which it is filed, timber operations may commence immediately.  If the notice has been filed by mailing, operations may commence three days after the notice has been mailed.