LOCATION CALPINE CA+NVEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Aridic Haploxerolls
TYPICAL PEDON: Calpine coarse sandy loam--on a 1 percent slope under silver sagebrush and perennial grasses at 3,800 feet elevation--rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; moderate very thin platy structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine and few medium roots; many very fine tubular and interstitial pores; moderately acid (pH 5.8); clear smooth boundary.
A2--3 to 13 inches; dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; weak thick platy structure; soft, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; many very fine tubular and interstitial pores; moderately acid (pH 6.0); gradual smooth boundary. (Combined thickness of the A horizons is 10 to 14 inches)
ABt--13 to 21 inches; dark grayish brown (10YR 4/2) coarse sandy loam, very dark brown (10YR 2/2) moist; weak medium and coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, common fine and few medium roots; common very fine tubular and interstitial and few fine and medium tubular pores; few faint clay films lining pores and bridging sand grains; slightly acid (pH 6.1); clear smooth boundary. (6 to 8 inches thick)
Bt1--21 to 30 inches; brown (10YR 5/3) coarse sandy loam, dark yellowish brown (10YR 3/4) moist; weak coarse prismatic structure; hard, firm, nonsticky and nonplastic; common very fine and few fine and medium roots; common very fine tubular and interstitial and few fine and medium tubular pores; few faint clay films lining pores and bridging sand grains; slightly acid (pH 6.3); gradual smooth boundary.
Bt2--30 to 46 inches; variegated light yellowish brown (10YR 6/4) and yellow (10YR 7/6) coarse sandy loam, yellowish brown (10YR 5/4) moist; weak coarse prismatic structure; hard, firm, slightly sticky and slightly plastic; few very fine, fine and medium roots; common very fine tubular and interstitial and few fine and medium tubular pores; common faint clay films lining pores and bridging sand grains; slightly acid (pH 6.5); gradual smooth boundary. (Combined thickness of the Bt horizons is 19 to 38 inches)
C1--46 to 59 inches; light yellowish brown (10YR 6/4) loamy fine sand, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, firm, nonsticky and nonplastic; few fine and medium roots; many very fine interstitial and few fine and medium tubular pores; neutral (pH 6.6); clear wavy boundary. (13 to 17 inches thick)
C2--59 to 81 inches; light yellowish brown (10YR 6/4), dark reddish brown (5YR 3/2), and yellow (10YR 7/8) stratified coarse sand and sand, reddish yellow (7.5YR 6/6), yellowish red (5YR 5/8), and dark reddish brown (2.5YR 3/4) moist; massive; soft, friable, nonsticky and nonplastic; few very fine, fine and medium roots; many very fine interstitial and few very fine tubular pores; few fine masses of manganese accumulation; slightly acid (pH 6.5).
TYPE LOCATION: Plumas County, California; in Sierra Valley about 0.5 mile southwest of Beckwourth; in the NE 1/4 of the SE 1/4 of section 27, T. 23 N., R. 14 E.; USGS Portola 7.5 minute topographic quadrangle; 39 degrees 48 minutes 57 seconds north latitude and 120 degrees 23 minutes 28 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - The moisture control section (10 to 28 inches) is dry in all parts from June 15 through November 15 (157 days). It is moist throughout from December 15 through May 1. The soil temperature exceeds 41 degrees F. from about March 15 to December 1 (260 days) and exceeds 47 degrees F. from about April 15 to November 15; Aridic moisture regime that borders on xeric.
Mean annual soil temperature - 48 to 54 degrees F.
Mollic epipedon thickness - 10 to 18 inches.
Depth to base of cambic horizon - 30 to 50 inches.
Depth to fine stratification - 50 inches or more.
Particle-size control section - Clay content: 5 to 15 percent; Sand content: 60 to 75 percent, mainly medium sand through very coarse sand; Rock fragments: Averages 0 to 15 percent, mainly fine (2 to 5 mm diameter) gravel. Lithology of fragments are granitic rocks such as granodiorite.
Reaction - Moderately acid through neutral.
A horizon - Dry color: 10YR 4/2, 4/3, 5/2, 5/3; 7.5YR 4/2, 5/2.
Moist color: 10YR 2/2, 3/2, 3/3 or 7.5YR 3/2.
Texture: Coarse sandy loam, sandy loam, fine sandy loam, or loam.
Rock fragments: 0 to 15 percent.
Organic matter content: 1 to 7 percent.
Bt or Bw horizons - Dry color: 10YR 5/3, 5/4, 6/3, 6/4, 7/6; 7.5YR 6/4 or 5/4.
Moist color: 10YR 3/3, 3/4, 4/4 or 7.5YR 3/4.
Texture: Fine sandy loam, sandy loam, or coarse sandy loam; Strata of loamy sand or loamy coarse sand are present in some pedons.
Structure: Weak prismatic, angular blocky, or subangular blocky.
Other features: There is commonly a clay increase of 1 to 2 percent from the overlying horizon which is insufficient to meet the requirements of an argillic horizon. Clay films range from none to common faint films bridging mineral grains.
C horizons - Dry color: 10YR 5/4, 6/3, 6/4, 7/8 or 5YR 3/2.
Moist color: 10YR 3/4, 4/3, 4/4; 7.5YR 6/6; 5YR 5/8 or 2.5YR 3/4.
Texture: Stratified coarse sand to loamy fine sand or stratified gravelly loamy sand to gravelly coarse sandy loam.
Clay content: 4 to 15 percent.
Rock fragments: 5 to 30 percent gravel.
COMPETING SERIES: These are the Burch, Cashmere, Cashmont, Rio King, Roloff, Roosevelt, and Snake Hollow series.
Burch soils have less than less than 60 percent sand and are not dominated by medium sand through very coarse sand in the particle-size control section. Cashmere soils are slightly alkaline or moderately alkaline in the lower part of the control section and do not have faint clay films lining pores and bridging sand grains. Cashmont have 15 to 35 percent rock fragments in the particle-size control section. Rio King soils have less than less than 60 percent sand and are not dominated by medium sand through very coarse sand in the particle-size control section and have endosaturation within 6 feet of the soil surface. Roloff and Roosevelt soils are moderately deep to lithic contacts. Snake Hollow soils are slightly alkaline through strongly alkaline.
GEOGRAPHIC SETTING: Calpine soils are on alluvial fans, fan remnants, and stream terraces. They formed in alluvium derived mainly from granitic rocks. Slopes are 0 to 15 percent. Elevations range from 3,000 to 6,000 feet. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 10 to 16 inches. The mean January temperature is about 28 degrees F. in northeastern California and about 40 degrees F. in southern California. The mean July temperature is about 68 degrees F. in northeastern California and about 72 degrees F. in southern California. The mean annual temperature is 48 to 53 degrees F. The frost-free period is 60 to 130 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the La Posta, Lovejoy, Mottsville, and Oak Glen soils. La Posta soils are moderately deep to paralithic contacts. Lovejoy soils are fine, have argillic horizons, and are moderately deep to duripans. Mottsville soils are sandy. Oak Glen soils have thick mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; very low or low surface runoff; moderately rapid permeability (high saturated hydraulic conductivity).
USE AND VEGETATION: Calpine soils are used principally for rangeland. A few areas are used for irrigated agriculture with alfalfa hay and pasture as the main crops. The vegetation in rangeland is mountain big sagebrush, antelope bitterbrush, needleandthread, Thurber's needlegrass, and Indian ricegrass.
DISTRIBUTION AND EXTENT: Northeastern and southern California and western Nevada. These soils are moderately extensive. The series concept and main acreage is in MLRA 21, while other acreage occurs in MLRAs 19 and 20 in southern California, MLRA 22A in northern California, and MLRA 26 in western Nevada and eastern California.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
SERIES ESTABLISHED: Plumas County (Sierra Valley Area), California, 1973.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 13 inches (A1 and A2 horizons).
Cambic horizon - The zone from 21 to 46 inches (Bt1 and Bt2 horizons).
Particle-size control section - The zone from 10 to 40 inches (Bt1 horizon and parts of the A2, ABt, and Bt2 horizons).