California Code, Health and Safety Code - HSC § 18862.47

(a) “Temporary recreational vehicle park” is any area or tract of land where two or more lots are rented, leased, or held out for rent or lease to owners or users of recreational vehicles and that is established for one operation not to exceed 11 consecutive days, and is then removed.

(b) Notwithstanding subdivision (a), an area or tract of land zoned for agricultural purposes where two or more lots are rented, leased, or held out for rent or lease to accommodate owners or users of 12 or fewer recreational vehicles for the purpose of housing agricultural employees shall not be deemed a temporary recreational vehicle park for the purposes of the requirement to obtain an initial or annual permit to operate or pay any fees related thereto required by this part.