A. 
The purpose of this chapter is to provide a zone classification for those areas designated as open space by the county general plan so as to encourage the protection of mountainous, hilly upland, valley, agricultural, potential agricultural, fragile desert areas, and other mandated lands from fire, erosion, soil destruction, pollution and other detrimental effects of intensive land use activities.
B. 
It is the intent of this chapter to establish standards for land uses that will protect and preserve the environmental resources, scenic, natural features, and open space character of the county, while also providing for agricultural development and protection of existing agricultural areas from urban development or residential subdivision.
C. 
It is also the intent of this chapter to preserve agricultural areas open space around the more intensive urban areas of the county, while providing for compatible multiple use of nonagricultural lands which are principally held by federal and other public agencies.
(Ord. 943 § 4, 1994)
The following are the principal permitted uses of the OS zone:
A. 
Single-family dwelling, including the use of a mobilehome;
B. 
Farms and ranches for orchards, vineyards, field and truck crops, nurseries, greenhouses, vegetables, flower gardening and other enterprises carried on in the general field of agriculture, including agricultural activities directly related to the farm or such as the repair and maintenance of farm and ranch equipment operated on the property; farm and ranch vehicles used on the property; and vehicles used to haul farm and ranch products produced on the property;
C. 
Livestock ranches for raising, grazing, breeding, boarding of small animals except as otherwise provided for under Section 18.12.040;
D. 
Animal hospitals, except when the property is adjacent or abuts residential zoned property;
E. 
Wildlife refuges; hunting and fishing preserves;
F. 
Wilderness areas and wilderness uses.
(Ord. 943 § 4, 1994; Ord. 1323, 9/23/2025)
The following are accessory uses permitted in the OS zone:
A. 
Dwellings of persons regularly employed on the premises for agricultural or domestic duties; mobile homes; subject to the provisions of state law, may be used for this purpose;
B. 
Private garages, parking areas and other structures used for the storage of equipment appurtenant to a permitted use;
C. 
Home occupations, guest house, signs and advertising, subject to the provisions under Chapters 18.06 and 18.78;
D. 
Roadside stands, not exceeding four hundred square feet in floor area, for the sale of agricultural produce grown on the premises;
E. 
Signs and advertising for permitted, accessory or conditional uses in compliance with the provisions of Chapter 18.75 and subject to the provisions of Section 18.12.050;
F. 
Other uses and accessory buildings customarily appurtenant and clearly incidental to a permitted use including noncommercial agriculture.
(Ord. 943 § 4, 1994; Ord. 1007 § 5, 1998)
The following are the conditional uses of the OS zone:
A. 
Public stables, roping arenas, riding academies, parks, campgrounds, private recreational clubs, pack stations, lodges, resorts, and other recreational activities involving development or large assemblages of people;
B. 
Feed lot, dairies or commercial ranches for the raising of poultry, pigs, goats or rabbits when any of the foregoing are located on property adjacent to residential zoned property;
C. 
Public and quasi-public buildings and uses of recreational, religious, cultural or public service nature, excluding exterior storage, repair yards and warehouses;
D. 
Golf course;
E. 
Farm labor or camp;
F. 
Cemeteries, crematories, mausoleums and columbariums;
G. 
Airports, landing fields and airstrips;
H. 
Public and commercial refuse disposal sites;
I. 
Mining and processing of natural resources, including borrow pits, subject to the provisions of the California Surface Mining Act;
J. 
Animal hospitals (when parcel is adjacent to residential zoned property) and all commercial kennels;
K. 
Agriculturally oriented services, including those uses of land devoted to the provision of buying, selling, processing, storing, packaging and otherwise directly serving functions associated with the production of local agricultural products, and including the operation, storage and maintenance of equipment and implements, and motor vehicles and trailers primarily used to transport local agricultural products and livestock. Manufacturing other than the primary cleaning, sorting, packaging or conversion of local agricultural products is prohibited;
L. 
Second dwelling units, subject to the requirements and procedures set forth or referred to in Section 18.78.340;
M. 
Informational kiosks and off-site directional signs complying with the provisions of Chapter 18.75 and subject to the provisions of Section 18.12.050.
N. 
Commercial cannabis cultivation, which shall be 300 feet from all parcel lot lines, and shall comply with otherwise applicable yard requirements.
O. 
Non-volatile cannabis manufacturing pursuant to commercial cannabis license classification 6.
P. 
Cannabis microbusinesses pursuant to commercial cannabis license classification 12 combining only some or all of those uses otherwise permitted by this section.
Q. 
Hemp Cultivation. Industrial hemp cultivation shall be subject to odor, noise, pollen escape and visual resource mitigation requirements and shall be 300 feet from all parcel lot lines.
(Ord. 943 § 4, 1994; Ord. 997 § 7, 1998; Ord. 1007 § 6, 1998; Ord. 1221 § 8, 2018; Ord. 1236 § 4, 2018; Ord. 1323, 9/23/2025)
The following are minimum standards established for development in the OS zone, except as otherwise provided in this title or as modified for conditional uses:
A. 
Maximum height of buildings:
1. 
Principal buildings, two and one-half stories or thirty feet,
2. 
Accessory buildings, two stories or twenty-five feet, except sixty feet for farm buildings or ranch buildings;
B. 
Minimum parcel size, forty acres, except when a greater minimum area is established pursuant to Section 18.78.055;
C. 
Parcel width, five hundred feet;
D. 
Front yard, fifty feet;
E. 
Rear yard, fifty feet;
F. 
Side yard, fifty feet;
G. 
Distance between buildings on same parcel, ten feet;
H. 
Off-street parking spaces per dwelling unit, two spaces.
(Ord. 943 § 4, 1994)