LOCATION URTAH                   NV

Established Series
Rev. LNL/ELS/JVC
12/2019

URTAH SERIES


The Urtah series consists of moderately deep, well drained soils that formed in residuum and colluvium derived from limestone and dolomite. Urtah soils are on hills and mountains. Slopes are 30 to 50 percent. The mean annual precipitation is about 350 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, carbonatic, frigid Torriorthentic Haploxerolls

TYPICAL PEDON: Urtah gravelly loam--rangeland. (Colors are for dry soil unless otherwise noted.)

A1--0 to 10 cm; grayish brown (10YR 5/2) gravelly loam, dark brown (10YR 3/3) moist; moderate medium platy structure; soft, very friable, slightly sticky and slightly plastic; common fine and medium roots; many fine and medium interstitial pores; 25 percent gravel and 5 percent cobbles; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (8 to 15 cm thick)

A2--10 to 41 cm; light brownish gray (10YR 6/2) very gravelly sandy loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky and moderate coarse granular structure; soft, very friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; many fine and medium interstitial pores; 35 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (10 to 30 cm thick)

AC--41 to 66 cm; light brownish gray (10YR 6/2) extremely gravelly sandy clay loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common fine and medium, few coarse roots; many fine and medium interstitial pores; 50 percent gravel and 15 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); gradual smooth boundary. (15 to 25 cm thick)

C--66 to 91 cm; pale brown (10YR 6/3) extremely gravelly sandy clay loam, brown (10YR 4/3) moist; massive; soft, very friable, moderately sticky and moderately plastic; few fine, medium and coarse roots; common fine and medium interstitial pores; 60 percent gravel and 10 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); gradual smooth boundary.

R--91 cm; hard limestone bedrock.

TYPE LOCATION: Elko County, Nevada; about 13.75 miles south-southeast of Carlin on the southwest side of Pine Mountain; approximately 500 feet north and 700 feet east of the southwest corner of section 36, T. 31 N., R. 52 E.; USGS Ravens Nest 7.5 minute topographic quadrangle; latitude 40 degrees 31 minutes 15 seconds N. and longitude 116 degrees 4 minutes 2 seconds W.; WGS84 Decimal Degrees 40.5208333 latitude, -116.0672222 longitude.

RANGE IN CHARACTERISTICS:

Soil moisture - Usually moist from late fall through early spring; dry from early spring to late fall; Aridic moisture regime that borders on xeric.
Mean annual soil temperature - 7 to 8 degrees C.
Mollic epipedon thickness - 18 to 46 cm.
Depth to bedrock - 50 to 100 cm to a lithic contact.
Particle-size control section - Clay content: 18 to 25 percent;
Rock fragments: Averages 60 to 80 percent, mainly gravel and cobbles. Lithology of fragments is limestone and dolomite.
Effervescence - Strongly effervescent or violently effervescent, depending upon the presence of magnesium carbonate in the parent rock.
Calcium carbonate equivalent - 40 to 50 percent in the fine-earth fraction.
Other features - Some pedons have thin carbonate coats commonly on the bottoms of rock fragments but no horizon 15 cm or more thick has 5 percent or more by volume of identifiable secondary carbonates.


A1 and A2 horizons
Value: 4 through 6 dry, 2 through 4 moist.
Chroma: 1 through 3, except moist colors do not have value of 2 with chroma of 1.
Structure: Weak or moderate, very fine or fine granular, weak, medium or thick platy structure.
Clay content: 10 to 15 percent.
Organic matter content: 1 to 3 percent.
Other features: The calcium carbonate equivalent in the fine-earth fraction allows for moist value of 4 and dry value of 6 in the Mollic epipedon.


AC and C horizons
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Texture: Very gravelly sandy clay loam or extremely gravelly sandy clay loam.
Clay content: 20 to 25 percent.
Organic matter content: 0.5 to 1 percent.

COMPETING SERIES: There are currently no other series in this family.

GEOGRAPHIC SETTING: Urtah soils are on hills and mountains. These soils formed in residuum and colluvium derived from limestone and dolomite. Slopes are 30 to 50 percent. Elevations range from 2,042 to 2,500 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 330 to 380 mm and comes mostly as snow. The mean annual temperature is 6 to 7 degrees C. and the frost-free period is 55 to 75 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bobs and Chen soils. Bobs soils are loamy and shallow to petrocalcic horizons. Chen soils are clayey-skeletal and shallow to lithic contacts.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; moderate permeability (moderately high saturated hydraulic conductivity).

USE AND VEGETATION: Urtah soils are used mainly for livestock grazing, wood products, and wildlife habitat. The principal vegetation is singleleaf pinyon, Utah juniper, Wyoming big sagebrush, curlleaf mountainmahogany, Thurber's needlegrass, and bluegrasses.

DISTRIBUTION AND EXTENT: Northern Nevada. These soils are not extensive with about 1,400 acres of the series mapped to date. MLRA 25.

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

SERIES ESTABLISHED: Lincoln County (Meadow Valley Area), Nevada, 1971.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 41 cm (A1 and A2 horizons).
Lithic contact - The boundary at 91 cm to underlying hard, unweathered bedrock (R layer).

Particle-size control section - The zone from 25 to 91 cm (AC and C horizons and part of the A2 horizon).


The revision of August 2008 updates the taxonomic class from Loamy-skeletal, carbonatic, frigid Calcic Haploxerolls and moves the type location from Lincoln County to Elko County, Nevada.


National Cooperative Soil Survey
U.S.A.