Proceedings for the formation of a district within Napa County shall be commenced by a petition that is either of the following:
(a) Signed by 50 percent or more of the owners of 65 percent or more of the affected land.
(b) Signed by 65 percent or more of the owners of 50 percent or more of the affected land.
The petition shall be addressed to, and filed with, the board of supervisors of the county.