LOCATION RUGAR NV
Established Series
Rev. ARW-TSB-RLB-JBF
10/2019
RUGAR SERIES
The Rugar series consists of deep, well drained soils that formed in residuum derived from tuff siltstone, claystone and sandstone. These soils are on fan piedmont remnants with rock core, concave side slopes and foot slopes of hills and mountains. Slopes are 2 to 30 percent. The mean annual precipitation is about 400 mm and the mean annual temperature is about 6 degrees C.
TAXONOMIC CLASS: Fine, smectitic, frigid Pachic Argixerolls
TYPICAL PEDON: Rugar clay loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with less than 5 percent gravel, l percent cobbles and stones.
A1--0 to 5 cm; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak very fine and fine subangular blocky structure parting to moderate fine and medium granular; slightly hard, very friable, moderately sticky and moderately plastic; many very fine, common fine and few coarse roots; common very fine and few fine tubular pores; l0 percent gravel; neutral (pH 7.0); clear smooth boundary. (5 to 10 cm thick)
A2--5 to 51 cm; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium and coarse subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine, fine, medium and few coarse roots; many very fine, fine and few medium tubular pores; 5 percent gravel; neutral (pH 6.6); abrupt smooth boundary. (40 to 50 cm thick)
Bt1--51 to 69 cm; brown (10YR 5/3) clay, dark brown (10YR 3/3) moist; few, fine prominent reddish yellow (7.5YR 6/6) moist, iron mottles; moderate medium and coarse angular blocky structure; hard, firm, moderately sticky and very plastic; few very fine, fine and coarse roots; common very fine, fine and few medium tubular pores; common stress surfaces; few, fine iron-manganese nodules; 10 percent soft gravel and 2 percent cobbles; slightly acid (pH 6.2); clear wavy boundary. (15 to 30 cm thick)
Bt2--69 to 109 cm; yellowish brown (10YR 5/4) paragravelly clay, dark yellowish brown (10YR 4/4) moist; common fine and medium, prominent strong brown (7.5YR 5/6) moist, iron redox concentrations; moderate coarse and very coarse angular blocky structure; very hard, firm, very sticky and very plastic; few very fine roots; common very fine, fine and few medium tubular pores; common stress surfaces; few, fine iron-manganese nodules; 20 percent soft weathered gravel slightly acid (pH 6.2); clear wavy boundary. (40 to 61 cm thick)
Cr--109 to 150 cm; highly weathered soft siltstone maintaining primarily rock structure; common fine iron manganese nodules.
TYPE LOCATION: Elko County, Nevada; approximately 2 miles south of Bull Run Reservoir, about 500 feet west and 400 feet south of the northeast corner of section 29, T. 43 N., R. 52 E.; USGS Deep Creek 7.5 minute topographic quadrangle; latitude 41 degrees 36 minutes 10 seconds N and longitude 116 degrees 08 minutes 53 seconds W; WGS84 Decimal Degrees 41.6027778 latitude, -116.1480556 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist, moist in winter and spring, dry late July through late October; xeric soil moisture regime.
Mean annual soil temperature: 6 to 8 degrees C.
Mollic epipedon thickness: 60 to 90 cm.
Depth to base of argillic horizon: 100 to 150 cm.
Depth to paralithic contact: 100 to 150 cm.
Reaction: Slightly acid or neutral.
Particle-size control section - Clay percent: 40 to 55 percent.
Rock fragments: 5 to 15 percent, mainly gravel or paragravel.
Bt horizon
Value: 3 or 4 moist.
Chroma: 3 or 4 dry and moist.
Texture: Clay or gravelly clay.
Structure: Moderate medium, coarse and very coarse angular blocky; or weak medium prismatic.
Other features: Most fragments are siltstone, are soft and will slake after overnight soaking.
Cr horizon
Other features: Commonly has iron-manganese nodules.
COMPETING SERIES: These are the
Arva,
Broadhead,
Bumpheads,
Cristo,
Henefer,
Lostpepper,
Schnipps and
Sweitberg series.
Arva and
Schnipps soils lack an abrupt boundary between the A and Bt and have more than 15 percent coarse fragment in the particle-size control section.
Broadhead,
Henefer and
Lostpepper soils are over 150 cm deep to bedrock.
Bumpheads,
Cristo and
Sweitberg soils are moderately deep to bedrock.
GEOGRAPHIC SETTING: Rugar soils are on fan piedmont remnants with rock core, concave side slopes and foot slopes of hills and mountains. These soils formed in residuum derived from siltstone, tuff claystone and sandstone. Slopes are 2 to 30 percent. Elevations are 1,680 to 2,290 meters. The climate is cool semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 250 to 460 mm, the mean annual temperature is 4 to 7 degrees C, and the frost-free season is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Sumine,
Quarz,
Graley,
Tusel and
Erakatak soils. Graley soils have a lithic contact within 50 cm. Sumine, Quarz and Erakatak soils have a lithic contact within 50 to 100 cm. Tusel soils have a cryic temperature regime.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium to rapid runoff; moderately low saturated hydraulic conductivity.
USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is mainly mulesear wyethia, lupine, bluebunch wheatgrass, basin wildrye, bottlebrush squirreltail and oniongrass.
DISTRIBUTION AND EXTENT: Northeastern Nevada. These soils are of small extent. MLRA 25.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Northwest Elko County Area, Nevada, 1986.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon (pachic) - The zone from the surface of the soil to a depth of 69 cm (A1, A2 and Bt1, horizons).
Argillic horizon - The zone from about 51 to 109 cm (Bt1 and Bt2 horizons).
Paralithic contact - The boundary at 109 cm (The Cr layer).
Particle-size control section - The zone from 51 to 101 cm (Bt1 and part of Bt2 horizons).
National Cooperative Soil Survey
U.S.A.