LOCATION CARSON NV
Established Series
Rev. MAT-ELS-JVC
05/2016
CARSON SERIES
The Carson series consists of very deep, somewhat poorly drained soils that formed in alluvium derived from mixed sources. Carson soils are on flood plains. Slopes are 0 to 2 percent. The mean annual precipitation is about 127 mm and the mean annual temperature is about 12 degrees C.
TAXONOMIC CLASS: Very-fine, smectitic, mesic Halic Haploxererts
TYPICAL PEDON: Carson clay--rangeland. (Colors are for moist soil unless otherwise noted.)
A--0 to 10 cm; very dark brown (10YR 2/2) clay, very dark grayish brown (10YR 3/2) dry; 45 percent clay; moderate medium prismatic structure parting to moderate medium angular blocky; very firm, very hard, very sticky and very plastic; common fine roots throughout; common fine and medium tubular pores; slightly saline (EC is 6 dS/m); moderately alkaline (pH 8.4); clear wavy boundary. (5 to 10 cm thick)
Ayz--10 to 25 cm; very dark brown (10YR 2/2) clay, very dark grayish brown (10YR 3/2) dry; 45 percent clay; moderate fine and medium wedge structure parting to moderate medium subangular blocky; very firm, very hard, very sticky and very plastic; common fine and medium roots in cracks; common fine and medium tubular pores; few fine gypsum crystals in the matrix; common fine salt crystals in the matrix; moderately saline (EC is 12 dS/m); moderately alkaline (pH 7.9); clear wavy boundary. (10 to 15 cm thick)
Bssz1--25 to 40 cm; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; moderate fine and medium wedge structure parting to moderate fine angular blocky; very firm, very hard, very sticky and very plastic; common fine and medium roots between peds; common fine and medium tubular pores; common distinct intersecting slickensides tilted 60 degrees from horizontal; few fine faint black (10YR 2/1) masses of manganese accumulation and common medium prominent brown (7.5YR 4/4) masses of iron accumulation; common fine salt crystals disseminated in the matrix; strongly saline (EC is 18 dS/m); moderately alkaline (pH 7.9); gradual wavy boundary.
Bssz2--40 to 64 cm; black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; weak coarse prismatic structure parting to moderate coarse wedge structure; very firm, very hard, very sticky and very plastic; common fine roots between peds; common fine tubular pores; common distinct intersecting slickensides tilted 60 degrees from horizontal; many fine and medium prominent brown (7.5YR 4/4) masses of iron accumulation; many fine and medium salt crystals disseminated in the matrix; strongly saline (EC is 24 dS/m); moderately alkaline (pH 8.0); gradual wavy boundary. (combined thickness of the Bssz horizons 35 to 80 cm thick)
Bkssz--64 to 104 cm; very dark gray (10YR 3/1) clay, very dark grayish brown (10YR 3/2) dry; weak coarse prismatic structure parting to moderate coarse wedge structure; very firm, very hard, very sticky and very plastic; common fine roots between peds; common fine tubular pores; few distinct intersecting slickensides tilted 60 degrees from horizontal; many fine and medium prominent brown (7.5YR 4/4) masses of iron accumulation; many fine and medium salt crystals disseminated in the matrix; strongly saline (EC is 24 dS/m); secondary carbonates segregated as few fine and medium strongly effervescent masses; 4 percent calcium carbonate equivalent; moderately alkaline (pH 8.4); gradual wavy boundary. (40 to 60 cm thick)
Bkz--104 to 152 cm; dark gray (10YR 4/1) clay, gray (10YR 5/1) dry; moderate medium prismatic parting to moderate medium angular blocky structure; very firm, very hard, very sticky and very plastic; common fine tubular pores; many fine and medium prominent brown (7.5YR 4/4) masses of iron accumulation; common fine and medium salt crystals disseminated in the matrix; strongly saline (EC is 19 dS/m); secondary carbonates segregated as few fine strongly effervescent masses; 8 percent calcium carbonate equivalent; moderately alkaline (pH 8.1).
TYPE LOCATION: Churchill County, Nevada; in the Lahontan Valley about 2 miles northeast of Stillwater; approximately 2,860 feet east and 250 feet north of the southwest corner of section 32, T. 20 N., R. 30 E.; USGS Stillwater 7.5 minute topographic quadrangle; latitude 39 degrees 32 minutes 56.71 seconds N. and longitude 118 degrees 31 minutes 39.51 seconds W.; WGS84 Decimal Degrees 39.5490861 latitude, -118.5276417 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually saturated with water for at least 1 month in the lower part of the moisture control section, usually in the spring, unless artificially drained; dry in all parts in summer and fall unless irrigated.
Mean annual soil temperature: 12 to 14 degrees C.
Mollic epipedon thickness: 18 to 69 cm.
Depth to horizons with aquic conditions: 50 to 100 cm during seasonal spring periods of saturation with ground water and anaerobic conditions.
Cracks: Open more than 1 cm wide and extend from the surface to at least 50 cm in summer and fall of normal years, except where planted to alfalfa and irrigated regularly each month; closed in winter and spring and during other wet periods.
Particle-size control section - Clay content: 60 to 80 percent.
A or Ap horizons
Hue: 10YR through 5Y.
Value: 3 or 4 moist, 5 or 6 dry.
Organic matter content: 1 to 3 percent.
Reaction: Moderately alkaline through very strongly alkaline (up to pH 9.6).
B horizons
Hue: 10YR through 5Y.
Value: 3 or 4 moist, 4 through 6 dry.
Chroma: 1 or 2, dry or moist.
Organic matter content: 1 or 2 percent in upper subhorizons.
Reaction: Slightly alkaline through very strongly alkaline (up to pH 9.6).
Salinity (EC): 4 to 32 mmhos/cm.
Sodicity: SAR of 5 to 45, ESP of 15 to 40 percent.
Slickensides and wedge structure: Present in subhorizons within 25 cm of the soil surface and may occur as deep as 178 cm from the surface. Wedge-shaped peds occur in subhorizons of some pedons and are bounded on upper and lower faces by slickensides.
Redoximorphic features: Redox concentrations occur as masses of iron or manganese accumulation and range from few to many, fine to coarse, and distinct or prominent. Colors have hue of 5YR through 10YR, value of 2 through 5, and chroma of 1 through 6. Redox depletion of iron has occurred in the matrix and is often indicated by strong gleying.
Gypsum content: 0 to 5 percent.
Secondary gypsum and/or sodium sulfate: Crystals and masses range from few to many and fine to coarse where present, but they are absent in some horizons or pedons.
Other features: Some pedons have subhorizons with few masses of identifiable secondary carbonates; few thin (less than 3 cm) strata of sand or loamy textures occur in some pedons; some pedons have subhorizons with masses or lenses of organic carbon.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Carson soils are on flood plains. They formed in alluvium derived from mixed sources. Slopes are 0 to 2 percent. Elevations range from 1158 to 1219 meters. The climate is arid with cool, moist winters and hot, dry summers. The annual precipitation is 100 to 150 mm, the mean annual temperature is 11 to 13 degrees C, and the frost-free period is 120 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Stillwater and
Weishaupt soils. Stillwater soils are fine. Weishaupt soils are fine-loamy over clayey.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained; low saturated hydraulic conductivity. Drainage has been improved in many areas by drainage ditches and by diversion of water for irrigation. Endosaturation is present with an apparent seasonal high water table between 50 and 150 cm (Shallow to Deep free water occurrence classes) from April through June.
USE AND VEGETATION: Carson soils are used for irrigated cropland, livestock grazing, and wildlife habitat. Alfalfa, small grains, and grass-legume pastures are the main crops. The vegetation in rangeland is mainly black greasewood, seepweed, iodinebush, and inland saltgrass.
DISTRIBUTION AND EXTENT: Western Nevada. These soils are moderately extensive. MLRA 27.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Churchill County (Fallon Area), Nevada, 1909.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 64 cm (A, Ayz, Bssz1, and Bssz2 horizons).
Slickensides - The zone from 25 to 104 cm (Bssz1, Bssz2, and Bkssz horizons).
Identifiable secondary carbonates - The zone from 64 to 152 cm (Bkssz and Bkz horizons).
Aquic conditions - The conditions of endosaturation, reduction, and redoximorphic features between 50 and 150 cm at certain times during normal years (parts of the Bssz2, Bkssz, and Bkz horizons).
Particle-size control section - The zone from 25 to 100 cm (Bssz1 and Bssz2 horizons and part of the Bkssz horizon).
The revision of September 2008 updated the taxonomic class from Typic Natraquerts based on a pending revision to the Keys for Soil Taxonomy involving Natraquerts, the lack of a natric horizon, and a reinterpretation of the depth to aquic conditions. The typical pedon was also moved from the prior location in reclaimed cropland to a new type location that better represents the natural chemical properties of the Carson series.
The revision of August 2000 updated the taxonomic class from Fluvaquentic Vertic Endoaquolls to Typic Natraquerts, updated horizon designations, and clarified the vertic features displayed in this soil.
ADDITIONAL DATA: The new typical pedon has full characterization data by the Soil Survey Laboratory (SSL), Lincoln, NE, as user pedon ID 99NV001006 (pedon # 00P0244). The typical pedon at the previous series type location was sampled in 1959 and characterized by the soil survey laboratory in Riverside, CA as sample number S59Nev-1-2. The data is published in Soil Survey Investigations Report No. 23 on page 185. The current user pedon ID is 1959NV001002 (pedon # 40A3236).
National Cooperative Soil Survey
U.S.A.