LOCATION VERMDIG                 CA

Established Series
Rev. EWB/JVC/JBF
06/2017

VERMDIG SERIES

The Vermdig series consists of very deep, somewhat poorly drained soils that formed in slope alluvium derived from andesite, tuff-breccia, and tuff. Vermdig soils are on mountains. Slopes are 2 to 8 percent. The mean annual precipitation is about 500 mm and the mean annual temperature is about 4.4 degrees C.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive Aquic Argicryolls

TYPICAL PEDON: Vermdig loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 10 percent gravel.

A--0 to 5 cm; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots; common very fine and fine interstitial pores; moderately acid (pH 5.8); clear smooth boundary. (3 to 8 cm thick)

Bt1--5 to 20 cm; brown (7.5YR 5/3) gravelly sandy clay loam, dark brown (7.5YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine interstitial and tubular pores; few faint clay bridges between sand grains; many medium distinct brown (7.5YR 4/2) moist irregular zones of iron depletion; 20 percent gravel; moderately acid (pH 5.8); clear smooth boundary. (8 to 20 cm thick)

Bt2--20 to 33 cm; brown (7.5YR 5/3) gravelly loam, dark brown (7.5YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine and fine roots; common very fine interstitial and tubular pores; few distinct clay films on faces of peds and lining pores; many medium distinct brown (7.5YR 4/2) moist irregular zones of iron depletion and few fine distinct brown (7.5YR 4/4) moist irregular masses of iron accumulation in the matrix; 20 percent gravel; slightly acid (pH 6.1); clear smooth boundary. (10 to 23 cm thick)

Bt3--33 to 81 cm; light brown (7.5YR 6/3) gravelly loam, dark brown (7.5YR 3/4) moist; moderate medium subangular blocky structure; hard, very friable, moderately sticky and moderately plastic; common very fine and fine roots; common very fine interstitial and tubular pores; few distinct clay films on faces of peds and lining pores; common medium distinct brown (7.5YR 4/2) moist irregular zones of iron depletion; 20 percent gravel; slightly acid (pH 6.1); clear smooth boundary. (28 to 48 cm thick)

Bt4--81 to 99 cm; light brown (7.5YR 6/3) gravelly clay loam, brown (7.5YR 4/3) moist; moderate fine and medium subangular blocky structure; hard, very friable, moderately sticky and moderately plastic; few very fine and fine roots; common very fine interstitial and tubular pores; few distinct clay films on faces of peds and lining pores; common fine prominent strong brown (7.5YR 4/6) moist irregular masses of iron accumulation lining pores; 30 percent gravel; slightly acid (pH 6.1); clear smooth boundary. (0 to 30 cm thick)

Bt5--99 to 152 cm; light brown (7.5YR 6/4) gravelly clay loam, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; very hard, friable, very sticky and moderately plastic; few very fine and fine roots; common very fine interstitial and tubular pores; common distinct clay films on faces of peds and lining pores; common fine prominent strong brown (7.5YR 4/6) moist irregular masses of iron accumulation lining pores; 15 percent gravel; slightly acid (pH 6.1).

TYPE LOCATION: Alpine County, California; on the Toiyabe National Forest about 0.5 mile west of Monitor Pass; approximately 2,000 feet south and 1,000 feet east of the northwest corner of section 36, T. 10 N., R. 21 E.; Heenan Lake USGS 7.5 minute topographic quadrangle; 38 degrees 40 minutes 18.9 seconds north latitude and 119 degrees 37 minutes 42.2 seconds west longitude, WGS84 Decimal Degrees 38.6783889 latitude, -119.6283889 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section during late fall, winter, spring, and early summer; usually dry from mid-July through September for 60 to 80 consecutive days in the four months following the summer solstice; occasionally saturated in the upper 15 to 38 cm during March to May, commonly saturated within 100 cm and occasionally saturated within 75 cm of the surface March to July; typic xeric moisture regime.
Mean annual soil temperature: 4.4 to 8.3 degrees C.
Mean summer soil temperature: 11 to 15 degrees c.
Mollic epipedon thickness: 25 to 41 cm.
Depth to base of argillic horizon: More than 152 cm.
Sodium fluoride pH: 8.5 to 9.0.

Particle-size control section - Clay content: Averages 18 to 27 percent;
Rock fragments: Averages 15 to 35 percent, mainly pebbles. Lithology of fragments are volcanic rocks such as andesite, tuff-breccia, and 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.
Reaction: Moderately acid or slightly acid.

Bt1 and Bt2 horizons
Hue: 10YR or 7.5YR.
Chroma: 2 or 3, dry or moist.
Texture: Gravelly sandy clay loam, gravelly sandy loam, or gravelly loam.
Clay content: 18 to 25 percent.
Rock fragments: 15 to 35 percent.
Organic matter content: 1 or 2 percent.
Reaction: Moderately acid or slightly acid.
Redoximorphic features: Redox concentrations occur as masses of iron or manganese accumulation in the matrix, and redox depletions occur as irregular zones of iron and manganese loss in the matrix.

Bt3, Bt4, and Bt5 horizons (when present)
Hue: 10YR or 7.5YR.
Chroma: 3 or 4, dry or moist.
Texture: Gravelly sandy clay loam, gravelly clay loam, or gravelly loam.
Clay content: 25 to 35 percent.
Rock fragments: 15 to 35 percent.
Reaction: Moderately acid or slightly acid.
Redoximorphic features: Redox concentrations occur as masses of iron or manganese accumulation in the matrix, and redox depletions occur as irregular zones of iron and manganese loss in the matrix.

COMPETING SERIES: This is the Animas series. Animas soils are moderately deep to paralithic contacts.

GEOGRAPHIC SETTING: Vermdig soils are on mountains. They typically occur on toeslope positions. They formed in slope alluvium derived from andesite, tuff, and tuff-breccia. Slopes are 2 to 8 percent. Elevations range from 2,290 to 2,595 meters. The climate is subhumid-continental with cold, moist winters and cool, dry summers. The mean annual precipitation is 410 to 610 mm, the mean annual temperature is 2.8 to 5.6 degrees C, and the frost-free period is 30 to 60 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aspocket and Monibasin soils. Aspocket and Monibasin soils have mollic epipedons more than 40 cm thick and have bedrock within 100 to 152 cm of the soil surface.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained; very high surface runoff; moderately slow permeability (moderately high saturated hydraulic conductivity). Endosaturation is present with an apparent seasonal high water table between 75 and 100 cm (moderately deep free water occurrence class) from March to July. Cumulative annual duration class is Common. Episaturation is occasionally present within the upper 15 to 38 cm from March to May.

USE AND VEGETATION: Vermdig soils are used for rangeland, recreation, watershed, and wildlife habitat. The native vegetation is mainly silver sagebrush, bluegrass, and mat muhly.

DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are not extensive with about 125 acres of the series mapped to date. MLRAs 22A and 26.

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

SERIES ESTABLISHED: Alpine County (Toiyabe National Forest Area), California, 2006.

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 5 to 152 (Bt1, Bt2, Bt3, Bt4, and Bt5 horizons).
Aquic conditions - The conditions of endosaturation and reduction in horizons between 99 and 152 cm in normal years (Bt4 and Bt5 horizons).
Particle-size control section - The zone from 5 to 55 (Bt1 and Bt2 horizons and part of the Bt3 horizon).

The revision of October 2003 updated the taxonomic class from Fine-loamy, isotic Aquic Argicryolls. The isotic mineralogy class was based solely on the field determined values for sodium fluoride pH. Laboratory data on 15 bar water to clay ratio does not exist to verify the isotic mineralogy class.

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National Cooperative Soil Survey
U.S.A.