LOCATION DUNPHY                  NV

Established Series
Rev. CEJ-RLB-JVC-JBF
02/2016

DUNPHY SERIES

The Dunphy series consists of very deep, somewhat poorly drained soils that formed in volcanic ash and alluvium derived from volcanic rocks. Dunphy soils are on flood plains and alluvial flats. Slopes are 0 to 2 percent. The mean annual precipitation is about 180 mm and the mean annual temperature is about 10 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, mesic Duric Halaquepts

TYPICAL PEDON: Dunphy silt loam--rangeland. (Colors are for dry soil unless otherwise noted). The soil surface has a hard crust approximately 3 mm thick composed of sodium salts.

A1--0 to 3 cm; light gray (10YR 7/2) silt loam, brown (10YR 4/3) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine interstitial pores; very strongly alkaline (pH 9.6); abrupt smooth boundary. (3 or 5 cm thick)

A2--3 to 18 cm; light gray (10YR 7/2) silt loam, brown (10YR 4/3) moist; weak very thin and thin platy structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and medium, and few fine horizontal roots that are mainly saltgrass rhizomes; very few very fine tubular pores; violently effervescent; very strongly alkaline (pH 9.6); abrupt wavy boundary. (10 to 38 cm thick)

Cqk--18 to 56 cm; light gray (2.5Y 7/2) fine sandy loam, light olive brown (2.5Y 5/4) moist; massive; hard, friable, slightly sticky and slightly plastic; common very fine, and few fine roots; few very fine and fine tubular pores; common medium faint dark yellowish brown (10YR 4/4) moist masses of iron accumulation; common medium distinct dark brown (10YR 3/3) and common medium prominent very dark brown (10YR 2/2) moist masses of iron-manganese accumulation; many very thin discontinuous olive brown (2.5Y 4/4) very hard, firm and brittle silica-cemented lenses and laminae; violently effervescent; very strongly alkaline (pH 9.6); clear wavy boundary. (13 to 50 cm thick)

2C--56 to 69 cm; very pale brown (10YR 7/3) fine sandy loam, light olive brown (2.5Y 5/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine, and few fine roots; few very fine tubular pores; common fine faint dark yellowish brown (10YR 4/4) and fine distinct dark yellowish brown (10YR 3/4) moist masses of iron accumulation; strongly effervescent; very strongly alkaline (pH 9.6); abrupt wavy boundary. (0 to 25 cm thick)

2Cq1--69 to 76 cm; light gray (5Y 7/2) very fine sandy loam, olive (5Y 5/3) moist; massive; very hard, firm and brittle, nonsticky and nonplastic; few very fine roots; few very fine tubular pores; common fine distinct dark yellowish brown (10YR 4/4) and common fine prominent dark yellowish brown (10YR 3/4) moist masses of iron-manganese accumulation; violently effervescent; very strongly alkaline (pH 9.4); clear wavy boundary. (3 to 15 cm thick)

2Cq2--76 to 89 cm; pale yellow (5Y 8/2) silt loam, light olive gray (5Y 6/2) moist; massive; hard, firm and brittle, slightly sticky and slightly plastic; very few very fine roots; common very fine tubular pores; common fine distinct olive (5Y 4/4) moist masses of iron accumulation; violently effervescent; very strongly alkaline (pH 9.2); abrupt wavy boundary. (3 to 15 cm thick)

3C--89 to 114 cm; pale yellow (5Y 7/3) loamy sand, olive (5Y 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; very few very fine roots; many very fine interstitial, and few very fine and fine tubular pores; common fine faint olive (5Y 5/4), olive (5Y 4/4), and common fine distinct olive (5Y 5/6) moist masses of iron accumulation; slightly effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary. (0 to 38 cm thick)

4Ckq--114 to 155 cm; light gray (5Y 7/2) silt loam, olive (5Y 5/3) moist; massive; hard, friable, slightly sticky and slightly plastic; common very fine and few fine tubular pores; fine distinct black (5Y 2/2) moist masses of manganese accumulation and few medium faint olive brown (2.5Y 4/4) moist masses of iron accumulation; secondary carbonates segregated as many coats lining pores; 60 percent very hard, firm and brittle durinodes with common silica bridges; violently effervescent; strongly alkaline (pH 8.8); abrupt wavy boundary. (0 to 40 cm thick)

5C--155 to 165 cm; light gray (5Y 7/2) gravelly sand, olive (5Y 5/3) moist; single grain; loose, nonsticky and nonplastic; many very fine and fine interstitial pores; slightly effervescent; strongly alkaline (pH 8.6).

TYPE LOCATION: Eureka County, Nevada; in the Whirlwind Valley about 2 miles west of Beowawe; USGS The Geysers 7.5 minute topographic quadrangle; approximately 1,440 feet east and 140 feet south of the northwest corner of section 1, T. 31 N., R. 48 E.; 40 degrees 35 minutes 45 seconds N and longitude 116 degrees 30 minutes 53 seconds W; WGS84 Decimal Degrees 40.5958333 latitude, -116.5147222 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section from mid-October through mid-July, dry from mid-summer through early fall; An apparent seasonal water table is between 75 to 100 cm early spring to early summer.
Mean annual soil temperature: 11 to 13 degrees C.
Ochric epipedon thickness: 13 to 38 cm.
Depth to horizons with durinodes or other forms of silica cementation: 15 to 43 cm.
Depth to horizons with firm consistence and a brittle manner of failure: 50 to 76 cm.
Calcium carbonate equivalent: 1 to 10 percent.
Reaction: Strongly alkaline or very strongly alkaline (up to pH 9.6).
Other features - Thin strata of volcanic ash up to 10 cmthick are in some pedons; some pedons have strongly cemented duripans at depths of 100 to 150 cm.

Particle-size control section - Clay content: Averages 8 to 15 percent.

A horizons
Hue: 10YR through 5Y.
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 2 through 4, dry or moist.
Consistence: Soft to very hard, dry. Very hard consistence is only in areas that are strongly affected by sodium. Consistence is never hard or very hard when massive.
Effervescence: Noneffervescent to violently effervescent.
Sodicity (SAR): 13 to 90.

C and Cq horizons
Hue: 10YR through 5Y.
Value: 6 through 8 dry, 4 through 6 moist.
Chroma: 2 through 4, dry or moist.
Texture: Stratified sandy loam to silty clay loam in the upper part and stratified gravelly sand to silt loam in the lower part
Consistence: Soft to extremely hard dry, very friable to firm moist, slightly sticky or nonsticky, slightly plastic or nonplastic, wet; a brittle manner of failure exists in the matrix when moist consistence is firm.
Effervescence: Effervescent throughout except for thin strata of volcanic ash in some pedons.
Sodicity (SAR): 13 to 90 in the upper part and 5 to 30 in the lower part.
Durinodes: Occurs as up to 70 percent durinodes, cemented lenses, or laminae in a friable or very friable matrix.
Redoximorphic features: Redox concentrations occur as yellowish hue, high chroma masses of iron accumulation and dark manganese masses in most pedons below a depth of 15 cm.

COMPETING SERIES: This is the Argenta series. Argenta soils have mean annual soil temperature of 8 to 11 degrees C. and do not have horizons with a matrix that has firm consistence when moist and a brittle manner of failure.

GEOGRAPHIC SETTING: Dunphy soils are on flood plains and alluvial flats. These soils formed in volcanic ash and alluvium derived from volcanic rocks. Slopes are 0 to 2 percent. Elevations range from 1,370 to 2,130 meters. The climate is arid with cool, moist winters and warm, dry summers. The mean annual precipitation is 150 to 200 mm, the mean annual temperature is 9 to 10 degrees C., and the frost-free period is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Iron Blossom, Ocala, and Rosney soils. Iron Blossom soils are fine-loamy. Ocala soils are fine-silty. Rosney soils are fine-silty and do not have accumulations of silica.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; low or medium surface runoff; moderately slow permeability; moderately high saturated hydraulic conductivity. These soils were formed under more poorly drained conditions than occur today. Entrenchment of stream channels, isolation due to stream meandering, and local alluvial faulting have improved the drainage. Endosaturation is present with an apparent seasonal high water table between 75 and 100 cm (moderately deep free water occurrence class) between March and June. Cumulative annual duration class is Common. Drained phases are recognized. Some phases are susceptible to rare flooding for very brief periods year-round.

USE AND VEGETATION: Dunphy soils are used for rangeland and wildlife habitat. The present vegetation is mainly rubber rabbitbrush, inland saltgrass, black greasewood, suaeda, and salt-tolerant annuals.

DISTRIBUTION AND EXTENT: Northern and central Nevada. These soils are moderately extensive. The series concept and main acreage is in MLRA 24, while other acreage occurs in MLRA 28B.

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

SERIES ESTABLISHED: Eureka County (Tuscarora Mountain Area), Nevada 1979.

REMARKS: This revision of May 2003 updates the taxonomic class from Coarse-loamy, mixed, superactive, calcareous, mesic Aeric Halaquepts. Future study is needed to determine the amount of volcanic glass in this series and whether the taxonomic class should be changed to Ashy, glassy, calcareous, mesic Aquandic Halaquepts.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A1 and A2 horizons).
Durinodes - The zone from 114 to 155 cm (4Ckq horizon).
Duric feature - The zones from 8 to 56 cm and 69 to 89 cm (Cqk, 2Cq1, and 2Cq2 horizons).
Endosaturation feature - The condition of ground water with an upper boundary between 75 and 100 cm at certain times during normal years (2Cq2 and 3C horizons).
Particle-size control section - The zone from 25 to 100 cm (2C, 2Cq1, and 2Cq2 horizons and parts of the Cqk and 3C horizons).

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National Cooperative Soil Survey
U.S.A.