LOCATION LUNSFORD CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aquic Haploxerolls
TYPICAL PEDON: Lunsford loam on a west facing 2 percent slope under a cover of perennial grasses at an elevation of 4240 feet. (Colors are for dry soil unless otherwise stated. When described July 12, 1987, the soil was moist throughout and ground water was at a depth of 42 inches).
Ap1--0 to 4 inches; gray (10YR 5/1) loam, very dark gray (10YR 3/1) moist; moderate fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many fine and medium roots throughout; common very fine tubular pores; violently effervescent; strongly alkaline (pH 8.6); abrupt smooth boundary.
Ap2--4 to 7 inches; gray (10YR 5/1) loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many fine and medium roots throughout; common very fine tubular pores; violently effervescent; strongly alkaline (pH 8.7); abrupt smooth boundary.
Ap3--7 to 13 inches; gray (10YR 5/1) loam, very dark grayish brown (10YR 3/2) moist; moderate medium platy structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots throughout; common very fine tubular pores; violently effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (Combined thickness of the Ap horizon is 13 to 15 inches)
Bt1--13 to 20 inches; light gray (10YR 7/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate fine subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; few fine roots; many fine tubular pores; few thin clay films in pores; violently effervescent; moderately alkaline (pH 8.3); clear smooth boundary.
Bt2--20 to 29 inches; light gray (10YR 7/2) sandy clay loam, brown to dark brown (10YR 4/3) moist; massive; hard, firm, nonsticky and slightly plastic; few fine roots throughout; many fine tubular pores; few thin clay films in pores; violently effervescent; moderately alkaline (pH 8.1); clear smooth boundary. (Combined thickness of the Bt horizon is 16 to 18 inches)
Bq1--29 to 36 inches; white (10YR 8/1) sandy clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, firm, slightly sticky and slightly plastic; few fine roots throughout; many very fine, common fine and medium tubular pores; 5 percent durinodes, secondary silica in pores; very slightly effervescent; moderately alkaline (pH 7.9); clear smooth boundary.
Bq2--36 to 49 inches; white (10YR 8/1) sandy clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, firm, slightly sticky, and slightly plastic; few very fine roots throughout; many very fine, common fine and medium, tubular pores; 5 percent durinodes, secondary silica in pores; very slightly effervescent; mildly alkaline (pH 7.8).
Bq3--49 to 55 inches; white (10YR 8/1) sandy clay loam, grayish brown (2.5Y 5/2) moist; massive, hard, firm, slightly sticky and slightly plastic; few very fine roots; many very fine, common fine and medium tubular pores; weakly cemented discontinuous matrix with 20 percent strongly cemented durinodes; very slightly effervescent; mildly alkaline (pH 7.8); clear wavy boundary. (Combined thickness of the Bq horizon is 20 to 30 inches).
C--55 to 72 inches; white (10YR 8/1), sandy clay loam, grayish brown (2.5Y 5/2) moist; massive; hard, firm, slightly sticky and slightly plastic; many very fine, common fine and medium tubular pores; very slightly effervescent; mildly alkaline (pH 7.8)
TYPE LOCATION: Lassen County, California; about 700 feet west and 1,900 feet north of the southeast corner of sec. 8, T. 38 N., R. 9 E., Adin northwest (Adin) Quadrangle (7.5 minute series).
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 50 to 52 degrees F. The soil temperature exceeds 41 degrees F. from early March to early December (275 days) and exceeds 47 degrees F. from mid April to early November. The soil moisture control section (7 to 20 inches) is dry in all parts from early August to mid September (40 to 50 days) and is moist in all parts from early October to mid July. The particle-size control section (10 to 40 inches) average ranges from 18 to 25 percent clay.
The Ap horizon color is 10YR 4/1 or 5/1. Clay content ranges from 15 to 20 percent. Organic matter ranges from 4 to 7 percent. Calcium carbonate equivalent ranges from 10 to 15 percent and is disseminated.. Electrical conductivity ranges from 0.7 to 1.5 mmhos/cm. Exchangeable sodium percentage ranges from 4 to 7 percent. Base saturation ranges from 95 to 100 percent.
The Bt horizon color is 10YR 6/2, 7/2, or 7/3. Moist color is 10YR 3/2, 4/2, 4/3, 5/2 or 5/3. Clay content ranges from 20 to 25 percent. Organic matter ranges from 2 to 3 percent. Calcium carbonate equivalent ranges from 2 to 11 percent and is disseminated. Electrical conductivity is less than 1.0 mmhos/cm. Exchangeable sodium percentage is 4 to 15 percent. Base saturation ranges from 90 to 100 percent.
The Bq horizon color is 10YR 7/3, 8/1 or 8/2. Moist color is 10YR 5/3; or 2.5Y 5/2. Texture is stratified sandy clay loam to silty clay loam. Clay content is 25 to 30 percent.
COMPETING SERIES: This is the Orting (WA) series. Orting soils do not have Bq horizons.
GEOGRAPHIC SETTING: Lunsford soils are on stream terraces. Slopes are 0 to 2 percent. These soils formed in mixed alluvium weathered from sedimentary and extrusive igneous rock. Elevation is 4180 to 4260 feet. The climate is semiarid with warm dry summers and cold moist winters. Mean annual precipitation is 14 to 16 inches. Snowfall is 12 to 24 inches. The mean annual temperature is 48 to 50 degrees F. The mean January temperature is about 32 degrees F. The mean July temperature is about 67 degrees F. Frost-free period is 100 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dotta, Henhill, Oxendine, and Sweagert soils. Dotta soils are on terraces, are fine-loamy, and have argillic horizons. Henhill soils are on stream terraces, are fine-loamy, have thick mollic epipedon, and argillic horizons. Oxendine soils are on intermounds, are shallow to a duripan, and are loamy. Sweagert soils are on mounds, are moderately deep to a duripan, and are fine-loamy.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; ponded to slow runoff; moderately slow permeability. The soils are flooded for periods of 7 days in December to April. A fluctuating water table occurs at depths of 30 to 40 inches from May to October and 12 to 24 inches from November to April.
USE AND VEGETATION: This soil is dominantly used for pasture. Small areas are used for hay production. The vegetation is basin wildrye, beardless wildrye, rushes, and sedges. Soils are cropped to alfalfa and grass hay.
DISTRIBUTION AND EXTENT: Northeastern California. The soils are not extensive. MLRA is 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Lassen County, Intermountain Soil Survey Area, California 1994. Source of name is a spring.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon- the zone from 0 to 13 inches (Ap1, Ap2, Ap3)
Cambic horizon- the zone from 13 to 29 inches (Bt1, Bt2)
Aquic subgroup - The aquic subgroup was based on low chromas in the matrix even though there was no additional redox concentrations
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.
ADDITIONAL DATA: NSSL characterization sample number S-84-CA-035-010.
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.