LOCATION WICUP                   NV

Established Series
Rev. HDP-DWW-JVC-JBF
12/2019

WICUP SERIES

The Wicup series consists of moderately deep, well drained soils that formed in residuum and colluvium derived from tuff with a component of loess. Wicup soils are on pediments and hills. Slopes are 2 to 15 percent. The mean annual precipitation is about 280 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Aridic Argixerolls

TYPICAL PEDON: Wicup silty clay loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partially covered with 30 percent gravel.

A--0 to 8 cm; grayish brown (10YR 5/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure; slightly hard, very friable, moderately sticky and moderately plastic; many very fine and few fine roots; many very fine interstitial and common fine tubular pores; 7 percent gravel; neutral (pH 6.9); abrupt smooth boundary. (5 to 13 cm thick)

Bt1--8 to 25 cm; brown (10YR 5/3) silty clay loam, dark brown (10YR 3/3) moist; weak fine prismatic structure parting to strong fine and medium angular blocky; hard, firm, moderately sticky and moderately plastic; common very fine and few fine roots; many very fine interstitial pores; few faint clay films on faces of peds and lining pores; 5 percent gravel; neutral (pH 7.2); abrupt smooth boundary. (10 to 20 cm thick)

Bt2--25 to 33 cm; brown (10YR 5/3) silty clay, dark brown (10YR 3/3) moist; strong medium prismatic structure; very hard, very firm, very sticky and very plastic; common very fine and few medium roots between peds; common very fine interstitial pores; common pressure faces on peds; 3 percent gravel; neutral (pH 7.2); clear wavy boundary. (5 to 15 cm thick)

Bt3--33 to 46 cm; yellowish brown (10YR 5/4) silty clay, brown (10YR 4/3) moist; strong medium prismatic structure; very hard, very firm, very sticky and very plastic; common very fine and few medium roots between peds; common very fine interstitial pores; common pressure faces on peds; 5 percent gravel; slightly alkaline (pH 7.4); clear wavy boundary. (10 to 20 cm thick)

Btkq--46 to 76 cm; pale brown (10YR 6/3) silty clay loam, yellowish brown (10YR 5/4) moist; moderate fine and medium prismatic structure; hard, firm, moderately sticky and moderately plastic; few very fine roots between peds; common very fine interstitial pores; few faint clay films on faces of peds; 4 percent gravel; common thin silica coats on faces of peds; secondary carbonates segregated as common very fine coats within the matrix; violently effervescent; moderately alkaline (pH 8.0); clear irregular boundary. (20 to 36 cm thick)

Cr--76 to 155 cm; pale brown (10YR 6/3) soft tuff, yellowish brown (10YR 5/4) moist; common large faint iron mottles; violently effervescent.

TYPE LOCATION: Elko County, Nevada; approximately 18 miles northeast of Wells; about 2,200 feet north and 330 feet west of the southeast corner section 6, T. 38 N., R. 65 E.; USGS Holborn 7.5 minute topographic quadrangle; latitude 41 degrees 12 minutes 17 seconds N and longitude 114 degrees 39 minutes 54 seconds W; WGS84 Decimal Degrees 41.2047222 latitude, -114.6650000 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring, dry from late June through October; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 11 degrees C.
Mollic epipedon thickness: 20 to 38 cm; includes the Bt1 horizon and in some pedons also includes the Bt2 horizon.
Depth to base of argillic horizon: 66 to 100 cm.
Depth to horizon with secondary carbonates and silica: 46 to 56 cm.
Depth to bedrock: 66 to 100 cm to a paralithic contact. The paralithic materials below the contact are soft tuff.

Particle-size control section - Clay content: 35 to 50 percent.
Rock fragments: 5 to 20 percent, mainly gravel with up to 5 percent cobbles. Lithology of fragments is volcanic rocks such as tuff.

A horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 to 3 percent.

Bt1 and Bt2 horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Clay loam, silty clay loam, silty clay, clay, or gravelly clay loam.
Clay content: 35 to 50 percent.
Rock fragments: 5 to 25 gravel
Structure: Weak or moderate, fine or medium, prismatic or angular blocky parting to angular or subangular blocky.
Reaction: Neutral or slightly alkaline.
Organic matter content: 1 to 3 percent.

Bt3 horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 through 5, dry or moist.
Texture: Clay loam, silty clay loam, silty clay, clay, or gravelly clay loam.
Clay content: 35 to 50 percent.
Rock fragments: 5 to 25 percent gravel.
Reaction: Neutral or slightly alkaline.

Btkq horizon
Hue: 10YR or 7.5YR.
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 through 5, dry or moist.
Texture: Clay loam, silty clay loam, silty clay, clay, or gravelly clay loam.
Clay content: 35 to 50 percent.
Rock fragments: 5 to 25 percent gravel.
Reaction: Slightly alkaline or moderately alkaline.
Secondary silica: Most pedons have few to common silica coats on faces of peds.
Identifiable secondary carbonates: Occurs as few coats on faces of peds or within the matrix.
Calcium carbonate equivalent: 1 to 3 percent.

COMPETING SERIES: These are the Brownscombe, Bucklake, Cagle, Correco, Holmzie, Jasseek, Northmore, Perla, Schoer, Sherar, and Zymans series.

Brownscombe soils have more than 15 percent coarse sand and very coarse sand in the particle-size control section and do not have secondary carbonates within 76 cm. Bucklake and Perla soils are moderately deep to lithic contacts. Cagle and Holmzie soils do not have secondary carbonates. Correco, Jasseek, Northmore, and Schoer soils are very deep. Sherar soils have subhorizons of the argillic horizon with more than 35 percent rock fragments and do not have secondary carbonates. Zymans soils are deep and very deep to paralithic contacts.

GEOGRAPHIC SETTING: Wicup soils are on pediments and hills. These soils formed in residuum and colluvium derived from tuff with a component of loess. Slopes are 2 to 15 percent. Elevations range from 1,800 to 1,955 mm. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 250 to 300 mm, mean annual temperature is 6 to 9 degrees C, and the frost-free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Akler, Booford, Gochea, and Gumble soils.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Wicup soils are used for rangeland and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush, Thurber's needlegrass, Sandberg's bluegrass, and thickspike wheatgrass.

DISTRIBUTION AND EXTENT: Northeastern Nevada. These soils are not extensive with about 6,300 acres of the series mapped to date. MLRA 25.

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

SERIES ESTABLISHED: Elko County (Northeast Part), Nevada, 1986.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 33 cm (A, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 8 to 76 cm (Bt1, Bt2, Bt3, and Btkq horizons).
Identifiable secondary carbonates - The zone from 46 to 76 cm (Btkq horizon).
Paralithic contact - The boundary at 76 cm to underlying soft bedrock (Cr layer).
Particle size control section - The zone from 8 to 58 cm (Bt1, Bt2, and Bt3 horizons and part of the Btkq horizon).

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National Cooperative Soil Survey
U.S.A.