LOCATION LERROW                  NV OR

Established Series
Rev. DWW-PWB-JVC-JBF
04/2019

LERROW SERIES

The Lerrow series consists of moderately deep, well drained soils that formed in residuum and colluvium derived mainly from volcanic rocks. Lerrow soils are on hills, mountains, and rock pediments. Slopes are 4 to 50 percent. The mean annual precipitation is about 300 mm and the mean annual temperature is about 6.6 degrees C.

TAXONOMIC CLASS: Fine, smectitic, frigid Vitritorrandic Argixerolls

TYPICAL PEDON: Lerrow gravelly ashy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The surface is partially covered with 30 percent gravel, 5 percent cobbles, and 1 percent stones.

A1--0 to 3 cm; brown (10YR 5/3) gravelly ashy loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine and few fine vesicular pores; 20 percent gravel; neutral (pH 6.8); clear smooth boundary. (2 to 8 cm thick)

A2--3 to 13 cm; brown (10YR 5/3) gravelly ashy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and common fine roots; common very fine tubular pores; 20 percent gravel; neutral (pH 7.1); clear smooth boundary. (3 to 18 cm thick)

Bt1-- 13 to 38 cm; brown (10YR 5/3) gravelly ashy clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine and few fine roots; many very fine tubular pores; common faint clay films on faces of peds; 15 percent gravel; neutral (pH 7.1); clear wavy boundary. (10 to 28 cm thick)

Bt2--38 to 61 cm; yellowish brown (10YR 5/4) cobbly clay, brown (10YR 4/3) moist; moderate medium angular blocky structure; hard, firm, very sticky and very plastic; common very fine and few fine roots; many very fine tubular pores; many distinct clay films on faces of peds and lining pores; 10 percent gravel, 15 percent cobbles, and 5 percent stones; neutral (pH 6.8); clear wavy boundary. (13 to 50 cm thick)

Bt3-- 61 to 81 cm; yellowish brown (10YR 5/4) gravelly clay, dark yellowish brown (10YR 4/4) moist; strong fine and medium prismatic structure; very hard, firm, very sticky and very plastic; common very fine roots; few very fine interstitial pores; many pressure faces; many distinct clay films on faces of peds and lining pores; 15 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.4); clear wavy boundary. (0 to 23 cm thick)

2Cr--81 to 104 cm; fractured, weathered andesite; common carbonate coats and clay films line fracture planes.

TYPE LOCATION: Elko County, Nevada; east of the Independence Mountains along a jeep trail south of Pie Creek; approximately 100 feet north and 1,100 feet east of the southwest corner of section 24, T. 39 N., R. 53 E.; USGS Reed Station 7.5 minute topographic quadrangle; latitude 41 degrees 14 minutes 56 seconds N and longitude 115 degrees 57 minutes 45 seconds W; WGS84 Decimal Degrees 41.2488889 latitude, -115.9625000 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist from late fall through spring, dry late June through October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 25 to 43 cm; includes the Bt1 horizon.
Depth to bedrock: 50 to 100 cm to a paralithic contact. The paralithic materials below the contact are weathered volcanic rocks such as andesite.
Reaction: Neutral or slightly alkaline, increasing with depth.

Particle-size control section - Clay content: 35 to 50 percent.
Rock fragments: 15 to 35 percent, mainly cobbles and gravel. Lithology of fragments is volcanic rocks such as andesite.

A horizons
Value: 5 or 6 dry; 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 2 or 3 percent.
Volcanic glass: Volcanic glass is estimated to range from 30 to 50 percent of the 0.2 to 2 mm fraction.

Bt1 horizon
Chroma: 2 or 3, dry or moist.
Texture: Ashy clay loam.
Clay content: 30 to 40 percent.
Rock fragments: 10 to 35 percent, mainly gravel.
Structure: Weak or moderate subangular blocky, or is platy.
Organic matter content: 1 or 2 percent.
Volcanic glass: Volcanic glass is estimated to range from 5 to 20 percent of the 0.2 to 2 mm fraction.

Bt2 and Bt3 horizons
Chroma: 3 or 4 moist.
Clay content: 40 to 55 percent.
Texture: Clay, gravelly clay, or cobbly clay.
Rock fragments: 15 to 35 percent; including 10 to 20 percent gravel, 0 to 5 percent stones, and 5 to 15 percent cobbles.
Structure: Subangular or angular blocky in the upper subhorizon, weak to strong, fine to coarse prismatic in the lower subhorizons.

COMPETING SERIES: These are the Drice and Martinson series.

Drice soils are moderately deep to lithic contacts. Martinson soils have 0 to 10 percent rock fragments and average 50 to 60 percent clay in their control section.

GEOGRAPHIC SETTING: Lerrow soils are on hills, mountains, and rock pediments. These soils formed in residuum and colluvium derived from volcanic rocks such as tuff, andesite, or rhyolite, sedimentary rocks such as shale or chert, or metamorphic rocks such as quartzite. Slopes are 4 to 50 percent. Elevations range from 1,500 meters to 2,270 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 250 to 360 mm, mean annual temperature is 5.5 to 7 degrees C, and the frost-free period is 70 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bullump, Chen, Cleavage, and Cotant soils. Bullump soils are loamy-skeletal, deep to lithic contacts, and have mollic epipedons 50 to 76 cm thick. Chen and Cleavage soils are shallow to lithic contacts. Cotant soils are shallow to paralithic contacts.

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

USE AND VEGETATION: Lerrow soils are used for rangeland and wildlife habitat. The vegetation is mainly mountain big sagebrush, antelope bitterbrush, Douglas rabbitbrush, bluebunch wheatgrass, basin wildrye, and Thurber's needlegrass.

DISTRIBUTION AND EXTENT: Northeastern Nevada. These soils are moderately extensive. MLRA 25.

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

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

REMARKS: December, 2008 revision changes classification from Aridic Argixerolls to Vitritorrandic Argixerolls to represent the volcanic ash component in the current Keys to Taxonomy.

Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 38 cm (A1, A2, and Bt1 horizons).
Argillic horizon - The zone from 13 to 81 cm (Bt1, Bt2, and Bt3 horizons).
Vitritorrandic feature - Volcanic glass is estimated to be 30 to 50 percent of the 0.02 to 2 mm fraction in the zone from 0 to 13 cm (A horizons) and 5 to 20 percent of the 0.02 to 2 mm fraction in the zone from 13 to 38 cm (Bt horizon).
Paralithic contact - The boundary at 81 cm to underlying weathered bedrock (2Cr layer).
Particle-size control section - The zone from 13 to 63 cm (Bt1 and Bt2 horizons and part of the Bt3 horizon).

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National Cooperative Soil Survey
U.S.A.