LOCATION HUNDRAW NV UT

Established Series
Rev. ARW-DWW-JB-JBF
11/2016

HUNDRAW SERIES

The Hundraw series consists of very shallow, well drained soils that formed in residuum and colluvium derived from tuff or sedimentary rocks with loess and volcanic ash. Hundraw soils are on hills and rock pediments. Slopes are 2 to 60 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 8 degrees C.

TAXONOMIC CLASS: Loamy, mixed, superactive, calcareous, mesic, shallow Xeric Torriorthents

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

A1--0 to 3 cm; light gray (2.5Y 7/2) gravelly loam, grayish brown (2.5Y 5/2) moist; moderate medium and thick platy structure; hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine interstitial, few fine vesicular and common fine and medium tubular pores; 25 percent gravel; strongly effervescent; moderately alkaline (pH 8.3); abrupt smooth boundary. (2 to 5 cm thick)

A2--3 to 8 cm; light gray (10YR 7/1) gravelly loam, dark grayish brown (10YR 4/2) moist; moderate thin and medium platy structure; slightly hard, very friable; slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine interstitial and tubular pores; 15 percent gravel; secondary carbonates segregated as coats on bottoms of gravel; strongly effervescent; moderately alkaline (pH 8.3); abrupt smooth boundary. (2 to 8 cm thick)

Bk--8 to 20 cm; light brownish gray (2.5Y 6/2) paragravelly loam, dark grayish brown (2.5Y 4/2) moist; weak fine and medium subangular blocky structure; slightly hard, very friable; slightly sticky and slightly plastic; common very fine, fine and medium roots; common very fine and fine horizontal roots at the lower horizon boundary; common very fine interstitial and few fine tubular pores; 5 percent gravel; 10 percent fine paragravel of tuff; secondary carbonates segregated as medium pendants on the bottoms of fragments; strongly effervescent; moderately alkaline (pH 8.3); abrupt smooth boundary. (5 to 13 cm thick)

Cr--20 cm; pale yellow (2.5Y 8/2) soft, fractured tuff, light brownish gray (2.5Y 6/2) moist; secondary carbonate coats and few very fine roots in fractures.

TYPE LOCATION: Elko County, Nevada; approximately 15 miles northwest of Montello; about 625 feet east and 1,625 feet south of the northwest corner of section 5, T. 40 N., R. 67 E.; USGS Ninemile Mountain 7.5 minute topographic quadrangle; latitude 41 degrees 22 minutes 44 seconds N and longitude 114 degrees 25 minutes 46 seconds W; WGS84 Decimal Degrees 41.3788889 latitude, -114.4294444 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the winter and spring, dry June through October; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 8 to 12 degrees C.
Depth to bedrock: 10 to 25 cm to a paralithic contact. The paralithic materials below the contact are weathered volcanic rocks such as tuff or sedimentary rocks such as siltstone.
Effervescence: Strongly effervescent or violently effervescent.
Calcium carbonate equivalent: 5 to 15 percent.
Other features: Some pedons do not have Bk horizons and the A horizon is underlain by C horizons.

Particle-size control section - Clay content: 5 to 18 percent.
Rock fragments: Averages 5 to 30 percent, mainly gravel.

A horizons
Hue: 7.5YR through 5Y.
Value: 6 or 7 dry, 3 through 5 moist.
Chroma: 1 through 4, dry or moist.

Bk and C horizons (when present)
Hue: 7.5YR through 5Y.
Value: 6 to 8 dry, 4 to 6 moist.
Chroma: 2 through 4, dry or moist.
Texture: Fine sandy loam or loam.
Clay content: 6 to 18 percent.
Rock fragments: Averages 5 to 34 percent.
Pararock fragments: 0 to 35 percent paragravel.
Structure: Weak or moderate, fine or medium subangular blocky or it is massive.

COMPETING SERIES: These are the Coppereid, Foxcan, Grina, Holborn, Jacratz, Puett, Stu, Tert, and Whilphang series.

Coppereid soils have mean annual soil temperatures of 11.5 to 14 degrees C. and have horizons with up to 30 percent pararock fragments of shale. Foxcan soils have less than 5 percent calcium carbonate. Grina soils are 36 to 50 cm to a paralithic contact and have 20 to 35 percent clay in the particle-size control section. Holborn soils have 18 to 30 percent clay in the particle-size control section. Jacratz soils have 25 to 35 percent clay in the particle-size control section. Puett soils are 25 to 50 cm to a paralithic contact. Stu soils are 25 to 50 cm to a paralithic contact and have mean annual soil temperatures of 12 to 13 degrees C. Tert soils have 18 to 27 percent clay in the particle-size control section. Whilphang soils are 25 to 50 cm to a paralithic contact and have mean annual soil temperatures of 12 to 15 degrees C.

GEOGRAPHIC SETTING: Hundraw soils are on hills and rock pediments. These soils formed in residuum and colluvium derived from tuffs and sedimentary rocks with loess and volcanic ash. Slopes are 2 to 60 percent. Elevations range from 1,650 to 2,135 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 300 mm, mean annual temperature is 6 to 10.5 degrees C, and the frost-free period is 100 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Izar and Kelk soils. Izar soils are loamy-skeletal and are very shallow to lithic contacts. Kelk soils are fine-silty, very deep, and have cambic horizons.

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

USE AND VEGETATION: Hundraw soils are used for livestock grazing and wildlife habitat. The present vegetation at the type location is mainly black sagebrush, Indian ricegrass, winterfat, bluegrass, phlox, and rabbitbrush.

DISTRIBUTION AND EXTENT: Northeastern Nevada and western Utah. These soils are moderately extensive. The series concept and main acreage is in MLRA 25, while other acreage occurs in MLRA 28B and 28A.

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:
Ochric epipedon - The zone from the soil surface to 18 cm (A1, A2 and part of the Bk horizons).
Paralithic contact - The boundary at 20 cm to underlying soft, fractured bedrock (Cr layer).
Particle-size control section - The zone from the soil surface to 20 cm (A1, A2, and Bk horizons).

National Cooperative Soil Survey
U.S.A.