LOCATION ZARARK                  NV

Established Series
Rev. BKP/TM/JBF
12/2016

ZARARK SERIES

The Zarark series consists of moderately deep, well drained soils that formed in colluvium and residuum derived from limestone and calcareous sandstone. Zarark soils are on backslopes and summits of mountains. Slope ranges from 4 to 75 percent. The mean annual precipitation is about 610 mm and the mean annual temperature is about 4.5 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic Pachic Calcicryolls

TYPICAL PEDON: Zarark very gravelly loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with approximately 20 percent gravel, and 20 percent cobbles.

A--0 to 10 cm; brown (10YR 5/3) very gravelly loam, dark brown (10YR 3/3) moist; moderate coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine interstitial pores; 40 percent gravel; slightly effervescent; moderately alkaline (pH 7.9); clear smooth boundary. (5 to 20 cm thick)

Bk1--10 to 45 cm; brown (10YR 4/3) very gravelly fine sandy loam, dark brown (10YR 3/3) moist; moderate coarse subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common very fine and fine interstitial pores; common medium secondary calcium carbonate concretions on the bottom of rock fragments; 16 percent calcium carbonate equivalent; 45 percent gravel, and 10 percent cobbles; violently effervescent; slightly alkaline (pH 7.5); clear smooth boundary. (10 to 40 cm thick)

Bk2--45 to 70 cm; brown (10YR 5/3) very gravelly sandy loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine, fine, and few medium roots; common very fine and fine interstitial pores; common medium secondary calcium carbonate concretions on the bottom of rock fragments; 45 percent calcium carbonate equivalent; 40 percent gravel and 15 percent cobbles; violently effervescent; moderately alkaline (pH 8.0); abrupt wavy boundary. (20 to 65 cm thick)

R--70 cm; fractured limestone.

TYPE LOCATION: White Pine County, Nevada; in the Schell Creek Range of the Humboldt-Toiyabe National Forest, about 1 mile east of the head of Gilford Creek; USGS Cleve Creek Baldy 7.5 minute topographic quadrangle; latitude 39 degrees 17 minutes 28.4 seconds N and longitude 114 degrees 39 minutes 18.8 seconds W; WGS84 Decimal Degrees 39.2912222 latitude, -114.6552222 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter, spring, and early summer, dry July and early August. Moist intermittently in the upper part from summer convection storms primarily in late August and September. This soil is dry in all parts at least 45 consecutive days following the summer solstice; typic xeric soil moisture regime.
Mean annual soil temperature: 4 to 7 degrees C.
Mean summer soil temperature: 8 to 10 degrees C.
Mollic epipedon thickness: 40 to 70 cm.
Depth to calcic horizon: 10 to 30 cm.
Depth to bedrock: 50 to 100 cm.
Reaction: Slightly alkaline or moderately alkaline.
Carbonate development stage: Stage 1
Calcium carbonate equivalent: 40 to 60 percent in the < 20 mm fraction.

Particle-size control section - Clay content: Averages 10 to 18 percent.
Rock fragments: averages 40 to 60 percent, mainly gravel. Lithology of the fragments is limestone.

O horizon (when present)
Slightly decomposed to highly decomposed organic material composed of curlleaf mountainmahogany leaves and twigs, and grass residues.

A horizon
Value 4 or 5 dry.
Organic matter: 2 to 4 percent.
Calcium carbonate equivalent: 10 to 15 percent.

Bk1 horizon
Value 4 or 5 dry.
Chroma: 3 or 4 dry and wet
Organic matter: 1.5 to 2 percent.
Texture: Loam, fine sandy loam, and sandy loam.
Rock fragments: Average 40 to 60 percent; mainly gravel.
Structure: Weak to moderate, fine through coarse subangular blocky.
Calcium carbonate: Few to common 1 to 2 mm thick concretions on the bottom of rock fragments.
Calcium carbonate equivalent: 15 to 25 percent in the less than 2 mm fraction.

Bk2 horizon
Value: 5 through 7 dry, and 3 through 7 moist.
Chroma: 2 or 3 moist.
Organic matter: 0.5 to 1.5 percent.
Texture: Sandy loam or fine sandy loam.
Rock fragments: Average 35 to 55 percent; mainly gravel, some pedons have thin subhorizons with 25 percent gravel.
Calcium carbonate: Few to common 3 to 5 mm thick concretions on the bottom of rock fragments.
Calcium carbonate equivalent: 25 to 45 percent in the less than 2 mm fraction.

COMPETING SERIES: These are the Coalkiln, Hardol, Meegero, and Wardbay series.

Coalkiln soils average 18 to 24 percent clay content in the particle-size control section, are very deep, and have an udic soil moisture regime with an annual average soil temperature of 3 to 5.5 degrees C. Hardol soils average 20 to 27 percent clay content in the particle-size control section and are very deep. Meegro soils are very deep. Wardbay soils average 18 to 27 percent clay content in the particle-size control section and have a depth to the calcic horizon of 38 to 64 cm.

GEOGRAPHIC SETTING: Zarark soils are on backslopes and summits of mountains. These soils formed in colluvium and residuum derived from limestone and calcareous sandstone. Slopes are 4 to 75 percent. Elevations range from 2,270 to 3,000 meters. The climate is subhumid, continental with cold, snowy winters and cool, dry summers. The mean annual precipitation is 450 to 700 mm, most of which is snow. Mean annual temperature is 3 to 6 degrees C, and the frost-free period is 40 to 60 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hardzem, Haunchee, Grink, Muiral, Successloop, and Wardbay soils. Hardzem and Muiral soils do not have mollic epipedons. Haunchee and Grink soils are shallow to bedrock. Successloop soils have a clay content of 27 to 35 percent.

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

USE AND VEGETATION: Zarark soils are used for recreation, livestock grazing, and wildlife habitat. The dominant native vegetation is a canopy of curlleaf mountainmahogany with an understory of bluebunch wheatgrass, snowberry, and mountain big sagebrush.

DISTRIBUTION AND EXTENT: Eastern Nevada. These soils are not extensive. MLRA 28B and 28A.

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

SERIES ESTABLISHED: White Pine County, Great Basin National Park, Nevada, 2009. The name is coined.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 70 cm (A, Bk1 and Bk2 horizons).
Calcic horizon - The zone from 10 to 70 cm (Bk1 and Bk2 horizons).
Lithic contact - The boundary at 70 cm (R layer).
Particle-size control section - The zone from 25 to 70 cm (lower part of Bk1 horizon and Bk2 horizon).

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National Cooperative Soil Survey
U.S.A.