LOCATION SUTHER CATentative Series
TAXONOMIC CLASS: Fine, smectitic, mesic Aquic Haploxeralfs
TYPICAL PEDON: Suther loam, rangeland. (Colors for dry soils unless otherwise noted).
A11--0 to 3 inches; pale brown (10YR 6/3) loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure; hard, friable, nonsticky, nonplastic; abundant very fine roots; many very fine and fine tubular pores; medium acid (pH 6.0); clear smooth boundary. (2 to 5 inches thick).
B1t--3 to 14 inches; pale brown (10YR 6/3) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; hard, friable, slightly sticky, slightly plastic; few fine roots; many very fine and fine tubular pores; medium acid (pH 6.0); clear smooth boundary. (6 to 14 inches thick).
B21t--14 to 24 inches; pale brown (10YR 6/3) gravelly clay, dark brown (10YR 4/3) moist; massive; very hard, very firm, sticky, very plastic; common very fine and fine tubular pores; many moderately thick clay films on peds, in pores, and as bridges; strongly acid (pH 5.5); diffuse wavy boundary. (8 to 12 inches thick).
B22t--24 to 36 inches; pale brown (10YR 6/3) gravelly clay, yellowish brown (10YR 5/6) with many fine distinct mottles of dark grayish brown (10YR 4/2) moist; massive; very hard, very firm, sticky, very plastic; common fine tubular pores; many moderately thick clay films on peds, in pores, and as bridges; medium acid (pH 6.0). (8 to 14 inches thick).
C--36 + inches; weathered and shattered sandstone.
TYPE LOCATION: Sonoma County, California, 3 1/2 miles northwest of Kellog in the SW 1/4, SW 1/4, of sec. 35, T10N, R8W.
RANGE IN CHARACTERISTICS: The soils have ochric epipedons (thickness and/or high values and chromas, dry or moist) and argillic horizons. Solum thickness is 24 to 45 inches to bedrock and mean annual soil temperature ranges from 52 to 55 degrees F. Mineralogy is mixed and the soils are dry most years for more than 60 consecutive days.
The A horizon colors dry are in 10YR and 7.5YR hues and have values of 5 or 6. Moist hues also are 10YR and 7.5YR and values are 2 to 4. Chromas are 2 or 3 dry and moist. Texture ranges from loam to gravelly loam, structure from weak to moderate subangular blocky, consistence from slightly hard to hard and friable, and reaction from slightly acid to medium acid.
The B horizon colors are in 10YR and 7.5YR hues with values of 5 or 6 dry and 4 or 5 moist, chromas are 3 to 6.
The Bt horizons have many fine distinct dark mottles. Texture ranges from gravelly clay to gravelly heavy clay loam. Structure is massive or weak coarse prismatic to angular blocky, and consistence is very hard, very firm, sticky and very plastic. Reaction is medium to strongly acid.
COMPETING SERIES: Included in the same family is the Zing series which has soils with umbric epipedons 10 inches or more thick. Also included are the Marvin, Modesto and Plaza soils in the fine, montmorillonitic, thermic family and the Yorkville soils in the mollic subgroup. The Sutherlin soils in the Typic subgroup lack mottles in the argillic horizon.
GEOGRAPHIC SETTING: The Suther soils occur on moderately steep to steep uplands underlain by sandstones and shale. Elevations are about 500 to 3,000 feet. The climate is subhumid mesothermal with mean annual rainfall of 35 to 50 inches, and with warm, dry summers and cool, wet winters. Mean annual temperature is about 52 to 55 degrees F., average January temperature about 48 degrees F., and average July temperature about 62 degrees F. Frost-free season is about 200 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: The Suther soils occur in the same general areas as the forested Hugo and Josephine soils, and the Sobrante and Supan soils on volcanic rocks.
DRAINAGE AND PERMEABILITY: Moderately well drained, permeability is slow and runoff is slow to rapid.
USE AND VEGETATION: The soils are used for range and pasture. Vegetation is annual grasses, oaks and shrubs.
DISTRIBUTION AND EXTENT: Northern California Coast Range. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Final correlation Sonoma County, California, 1966. The name is coined.
REMARKS: The Suther series formerly would have been classified in the Noncalcic Brown group.
OSED scanned by SSQA. Last revised by state on 5/67.