After the adoption of the first map provided for in RCW 36.70.740, and pending the time that all property within a county can be precisely zoned through the medium of a zoning map, all properties not so precisely zoned by map shall be given a classification affording said properties such broad protective controls as may be deemed appropriate and necessary to serve public and private interests. Such controls shall be clearly set forth in the zoning ordinance in the form of a zone classification, and such classification shall apply to such areas until they shall have been included in the detailed zoning map in the manner provided for the adoption of a zoning map.