LOCATION PULCAN                  NV

Established Series
Rev. DMC/GJS/JBF
06/2017

PULCAN SERIES

Pulcan series consists of moderately deep, well drained soils that formed in colluvium and residuum derived from mudstone. Pulcan soils are on terrace side slopes. Slopes are 15 to 30 percent. Mean annual precipitation is about 200 mm and mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Clayey-skeletal, smectitic, mesic Calcic Paleargids

TYPICAL PEDON: Pulcan very gravelly fine sandy loam--rangeland. (Colors are for dry soil unless otherwise stated.)

A1--0 to 5 cm; brown (10YR 5/3) very gravelly fine sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and medium roots; many very fine and few fine tubular pores; 40 percent gravel, 10 percent cobbles, and 5 percent stones; slightly acid (pH 6.1); abrupt wavy boundary. (3 to 8 cm thick)

A2--5 to 13 cm; pale brown (10YR 6/3) very gravelly loam, dark brown (10YR 3/3) moist; weak thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, common fine and medium roots; many very fine tubular and few fine interstitial pores; 40 percent gravel and 5 percent cobbles; neutral (pH 6.6); abrupt wavy boundary. (5 to 13 cm thick)

Bt1--13 to 23 cm; brown (10YR 5/3) very gravelly clay loam, brown (10YR 4/3) moist, dark brown (10YR 3/3) coating on ped faces; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine, common fine and few medium and coarse roots; many very fine tubular pores; many distinct clay films on ped faces and coating sand grains; 40 percent gravel and 5 percent cobbles; neutral (pH 6.8); clear wavy boundary. (8 to 15 cm thick)

Bt2--23 to 46 cm; brown (7.5YR 5/4) very gravelly sandy clay, brown (7.5YR 4/4) moist; moderate coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many very fine and few fine, medium, and coarse roots; many very fine tubular pores; continuous distinct clay films on ped faces and lining pores; 45 percent gravel and 5 percent cobbles; neutral (pH 6.8); clear wavy boundary. (18 to 30 cm thick)

Bt3--46 to 64 cm; pale brown (10YR 6/3) very gravelly sandy clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine and few medium and fine roots; many very fine tubular pores; common distinct clay films coating and bridging sand grains; 45 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.4); abrupt wavy boundary. (15 to 30 cm thick)

Bk--64 to 86 cm; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; weak fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, few fine and medium roots; many very fine tubular pores; 45 percent gravel; violently effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary. (13 to 30 cm thick)

Cr--86 cm; soft weathered mudstone; violently effervescent along fracture planes.

TYPE LOCATION: Douglas County, Nevada, about 9 miles east of Topaz Lake; 120 feet southwest of east 1/4 corner of section 28, T. 10 N., R. 23 E.; USGS Long Dry Canyon 7.5 minute topographic quadrangle; latitude 38 degrees 42 minutes 1 seconds N and longitude 119 degrees 24 minutes 15 seconds W; WGS84 Decimal Degrees 38.6993333 latitude, -119.4043056 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 9 to 11 degrees C.
Depth to Bk horizon: 58 to 76 cm.
Depth to paralithic contact: 71 to 100 cm.

Particle-size control section - Percent clay: 35 to 45 percent.
Rock fragments: 35 to 60 percent mostly gravel, with as much as 5 to l5 percent cobbles.

A1 horizon
Value: 5 or 6 dry, 2 through 4 moist.
Chroma: 2 or 3.

A2 horizon
Value: 5 or 6 dry, 2 through 4 moist.
Chroma: 2 or 3.
Rock fragments: 40 to 60 percent mainly gravel, with as much as 5 to l5 percent cobbles.

Bt horizons
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 through 4.
Textures: Dominantly very gravelly clay loam, very gravelly sandy clay and very gravelly clay with very gravelly sandy clay loam common in lower subhorizon.
Other features: Calcareous in lower subhorizons of some pedons.

C horizon
Value: 5 through 7 dry, 3 or 4 moist.
Chroma: 2 through 4.
Texture: Very gravelly sandy loam or very gravelly loamy sand.
Rock fragment: 35 to 60 percent, mostly gravel.
Other features: Calcareous throughout or has carbonate coating underside of rock fragments.

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

GEOGRAPHIC SETTING: Pulcan soils are on side slopes of old terraces, at elevations of 1,680 to 1,985 meters. Slopes are 15 to 30 percent. They formed in colluvium and residuum derived from tertiary mudstone, sandstone, and interbedded tuff. The summers are hot and dry and the winters are cold and wet. Precipitation is mostly snow in winter months and rain during spring months. The mean annual precipitation is 200 to 250 mm; mean annual temperature is 8 to 11 degrees C, and the frost-free season is 95 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Indian Creek, Puett, and Uhaldi soils. Indian Creek soils have a duripan within 50 cm. Puett soils lack an argillic horizon and are shallow over tertiary sediments. Uhaldi soils have a gravelly clay loam argillic horizon and a mollic epipedon.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; rapid runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Rangeland and wildlife habitat. The vegetation is principally low sagebrush, littleleaf horsebrush, Thurbers needlegrass, Sandberg bluegrass, and desert needlegrass.

DISTRIBUTION AND EXTENT: Western Nevada. The series is of small extent. MLRA 26.

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

SERIES ESTABLISHED: Douglas County Area, Nevada, 1981.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 13 cm (A1 and A2 horizons).
Argillic horizon - The zone from 13 to 64 cm (Bt1, Bt2, and Bt3 horizons).
Paralithic contact - The boundary at 86 cm to underlying weathered bedrock (Cr layer).
Particle-size control section - The zone from 13 to 63 cm (Bt1 and Bt2 horizons and part of the Bt3 horizon).

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National Cooperative Soil Survey
U.S.A.