LOCATION CHURCHILL NV

Established Series
Rev. ELS-WED-JVC
05/2016

CHURCHILL SERIES

The Churchill series consists of very deep, moderately well drained soils that formed in alluvium over lacustrine deposits derived from mixed rocks. Churchill soils are on basin-floor remnants. 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: Fine, smectitic, mesic Vertic Natrargids

TYPICAL PEDON: Churchill very gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 3 cm; light gray (10YR 7/1) very gravelly sandy loam, grayish brown (10YR 5/2) moist; weak medium platy structure; hard, friable, slightly sticky and slightly plastic; few fine roots; many fine, medium and coarse vesicular pores; 40 percent rock fragments that are dominantly gravel-size dendritic tufa fragments; violently effervescent; very strongly alkaline (pH 9.4); abrupt smooth boundary. (3 to 8 cm thick)

Btn1--3 to 10 cm; brown (10YR 4/3) clay loam, dark yellowish brown (10YR 4/4) moist; moderate fine and medium prismatic structure; hard, friable, moderately sticky and moderately plastic; few fine roots; many fine and medium tubular pores; common faint clay films on faces of peds and lining pores; violently effervescent; very strongly alkaline (pH 9.2); abrupt wavy boundary. (8 to 15 cm thick)

Btn2--10 to 23 cm; light olive brown (2.5Y 5/4) gravelly silty clay loam, olive brown (2.5Y 4/4) moist; weak medium subangular block structure; hard, friable, moderately sticky and moderately plastic; few fine roots; common fine and medium tubular pores; 30 percent gravel-size tufa fragments; few faint clay films on faces of peds, lining pores, and coating rock fragments; violently effervescent; strongly alkaline (pH 9.0); clear wavy boundary. (10 to 15 cm thick)

2C1--23 to 43 cm; light gray (2.5Y 7/2) silty clay, olive gray (5Y 5/2) moist; moderate fine angular blocky structure; hard, friable, very sticky and very plastic; few fine roots; many fine and medium tubular pores; strongly effervescent; strongly alkaline (pH 8.8); clear irregular boundary. (15 to 25 cm thick)

2C2--43 to 61 cm; light brownish gray (2.5Y 6/2) silty clay, grayish brown (2.5Y 5/2) moist; moderate coarse angular blocky structure; very hard, firm, very sticky and very plastic; few fine roots; few fine tubular pores; few fine prominent black (N 2/0) moist relict masses of manganese accumulation lining pores; slightly effervescent; strongly alkaline (pH 8.8); clear irregular boundary. (15 to 25 cm thick)

2C3--61 to 97 cm; light brownish gray (2.5Y 6/2) silty clay, grayish brown (2.5Y 5/2) moist; moderate coarse prismatic structure; very hard, firm, very sticky and very plastic; few fine tubular pores; few fine prominent black (N 2/0) moist relict masses of manganese accumulation lining pores and on faces of peds; slightly effervescent in spots; strongly alkaline (pH 8.8); abrupt smooth boundary. (23 to 41 cm thick)

2C4--97 to 157 cm; light gray (2.5Y 7/2) silty clay, grayish brown (2.5Y 5/2) moist; strong very coarse prismatic structure; very hard, firm, very sticky and very plastic; few fine tubular pores; few fine prominent black (N 2/0) moist relict masses of manganese accumulation lining pores and on faces of peds, and many fine distinct yellowish brown (10YR 5/4) moist relict masses of iron accumulation; many thin discontinuous lenses of tufa; common thin discontinuous lenses of yellowish brown (10YR 5/4) high micaceous fine sand; slightly calcareous in spots; strongly alkaline (pH 8.8).

TYPE LOCATION: Churchill County, Nevada; in the Lahontan Valley about 5 miles northeast of Fallon; approximately 1,320 feet west and 1,050 feet north of the southeast corner of section 14, T. 19 N., R. 29 E.; USGS Indian Lakes 7.5 minute topographic quadrangle; latitude 39 degrees 30 minutes 25.70 seconds N. and longitude 118 degrees 41 minutes 33.54 seconds W.; WGS84 Decimal Degrees 39.5071333 latitude, -118.6926500 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section for short periods in winter and spring, dry remainder of the year; typic aridic soil moisture regime.
Mean annual soil temperature: 12 to 14 degrees C.
Ochric epipedon thickness: 3 to 8 cm.
Depth to the base of natric horizon: 20 to 36 cm.
Depth to relict redoximorphic features: less than 50 cm.
Linear extensibility (LE): 6 to 9 cm.

Particle-size control section - Clay content: 40 to 50 percent.

A horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 1 or 2, dry or moist.

Btn horizons
Hue: 10YR or 2.5Y.
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture: Clay loam, silty clay loam, gravelly silty clay, gravelly silty clay loam, or gravelly clay.
Clay content: 35 to 45 percent.
Rock fragments: 5 to 25 percent gravel-size tufa fragments.
Reaction: Strongly alkaline or very strongly alkaline.
Salinity (EC): 16 to 32 mmhos/cm.
Sodicity (SAR): 30 to 150.
Other features: Tufa fragments range from discontinuous semi-restrictive layer to soft powdery masses with a hard core.

2C horizons
2.5Y or 5Y.
Value: 6 or 7 dry, 5 or 6 moist.
Chroma: 1 or 2, dry or moist.
Texture: Silty clay or clay.
Clay content: 40 to 55 percent.
Rock fragments: 0 to 10 percent.

COMPETING SERIES: This is the Uzacol series. Uzacol soils are deep to paralithic contacts, have hue of 5YR or 7.5YR, and have identifiable secondary carbonates and gypsum below the natric horizon.

GEOGRAPHIC SETTING: Churchill soils are on basin-floor remnants. These soils formed in alluvium over lacustrine deposits derived from mixed rocks. Slopes are 0 to 2 percent. Elevations range from 1,189 to 1,219 meters. The climate is arid with cool, moist winters and hot, dry summers. The mean 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: This is the Isolde soil. Isolde soils are sandy and occur on dunes.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; low saturated hydraulic conductivity. Endosaturation is present with an apparent seasonal high water table between 90 and 150 cm (moderately deep to very deep free water occurrence classes) between January and April. Cumulative annual duration class is Common.

USE AND VEGETATION: Churchill soils are used for rangeland and wildlife habitat. The present vegetation is mainly black greasewood, seepweed, and shadscale.

DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive with about 5,300 acres of the series mapped to date. MLRA 27.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Churchill County (Fallon-Fernley Area), Nevada, 1971.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 3 cm (A horizon).
Natric horizon - The zone from 3 to 23 cm (Btn1 and Btn2 horizons).
Vertic feature - The zone from the soil surface to 100 cm with linear extensibility of 6 cm or more.
Particle-size control section - The zone from 3 to 100 cm (Btn1, Btn2, 2C1, 2C2, and 2C3 horizons and part of the 2C4 horizon.)

The revision of March 2004 updated the taxonomic class from Fine, smectitic, mesic Typic Natrargids based on linear extensibility values in the NASIS database and the high shrink-swell limitation for many standard interpretations.

National Cooperative Soil Survey
U.S.A.