Established Series


The Friant series consists of shallow, well drained soils that formed in material weathered from mica schist, quartz schist and gneiss. Friant soils are on mountainous uplands and have slopes of 9 to 75 percent. The mean annual precipitation is about 18 inches and the mean annual air temperature is about 62 degrees F.

TAXONOMIC CLASS: Loamy, mixed, superactive, thermic Lithic Haploxerolls

TYPICAL PEDON: Friant fine sandy loam, annual grass range. (Colors are for dry soil unless otherwise noted.)

A1--0 to 3 inches; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) moist; weak fine and medium granular structure; slightly hard, friable, nonsticky and nonplastic; many fine roots; common fine tubular and many very fine interstitial pores; about 10 percent angular gravel fragments; slightly acid (pH 6.4); abrupt wavy boundary. (2 to 8 inches thick)

A2--3 to 14 inches; brown (10YR 5/3) fine sandy loam dark brown (10YR 3/3) moist; massive; slightly hard, friable, nonsticky and nonplastic; common fine roots; many fine tubular and interstitial pores; about 5 percent angular gravel fragments; neutral (pH 6.6); abrupt irregular boundary. (4 to 122 inches thick)

R--14 to 24 inches; gray and yellowish brown, slightly weathered quartz mica schist; reddish brown clay films coat some of the minor fracture and joint planes within the upper 6 inches of this horizon.

TYPE LOCATION: Fresno County, California; about 1/4 mile (airline) SSW of the SE end of Friant Dam; SW 1/4 NE1/4 NW1/4 of section 8, T.11S., R.21E.

RANGE IN CHARACTERISTICS: Depth to a lithic contact is 6 to 20 inches. The mean annual soil temperature just above the bedrock is 62 to 67 degrees F., and the soil temperature usually is not below 47 degrees F. Soil below a depth of about 6 to 8 inches is usually continuously moist from about November or early December until April or May and is dry all the rest of the year. Texture throughout is loam, sandy loam or fine sandy loam and has less than 18 percent clay. The soil is micaeous and the amount of mica ranges from small to large. Rock fragments, mostly angular or subangular pebbles, make up 5 to 35 percent of the soil.

The A horizon is brown, dark brown or dark yellowish brown, 10YR 5/2, 5/3, 4/2, 4/3, 4/4; 7.5YR 5/4, 4/4 when dry and dark brown, 10YR 3/3; 7.5YR 3/2, 3/3 when moist. Usually it has weak to moderate granular or subangular blocky structure. In some pedons, some or all of this horizon is massive and slightly hard when dry. It contains 1 to 3 percent organic matter. This horizon is neutral to medium acid and the base saturation is 75 to 100 percent. Some pedons have a C horizon of soil material 1 to 5 inches thick between the A horizon and bedrock. Such C horizons have dry value of 6 and moist chroma of 2 through 4, and less than 1 percent organic matter. All other properties are similar to the A horizon.

COMPETING SERIES: These are the Calleguas, Daulton, Exchequer, Gaviota, Hambright, Lodo, Lopez, and Millsholm series. Calleguas soils are moderately alkaline and have more than 35 percent rock fragments. Daulton, Exchequer, Gaviota and Millsholm soils have ochric epipedons. Hambright and Lopez soils have more than 35 percent rock fragments and Lopez soils have 50 to 75 percent base saturation. Lodo soils have 18 to 35 percent clay.

GEOGRAPHIC SETTING: Friant soils are on hilly and mountainous landscapes at elevations of 500 to 3,500 feet. Slopes range from 9 to 75 percent. The soils formed in residuum weathered from mica schist, quartz schist, and gneiss. The climate is subhumid mesothermal with warm, dry summers and cool, moist winters. The mean annual precipitation is 12 to 25 inches. The mean annual temperature is about 59 to 65 degrees F.; the average January temperature is 42 to 54 degrees F.; the average July temperature is about 72 to 78 degrees F. The frost free season is about 210 to 330 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cieneba, Escondido, Fallbrook, Sesame and Vista soils. Each of these soils lacks a mollic epipedon. Escondido, Fallbrook, Sesame and Vista soils lack a paralithic contact within a depth of 20 inches.

DRAINAGE AND PERMEABILITY: Well drained; medium to very rapid runoff; moderately rapid permeability.

USE AND VEGETATION: These soils are used principally for grazing, wildlife, and watershed. Native vegetation is buckwheat, chaparral, and naturalized grasses and forbs.

DISTRIBUTION AND EXTENT: Foothills along the east side of the San Joquin Valley and the southwestern part of southern California. The soils are moderately extensive.


SERIES ESTABLISHED: San Bernardino County (Southwestern Part), California, 1972.

National Cooperative Soil Survey