LOCATION SIMPARK                 NV

Established Series
Rev. WED-RAF-JVC-JBF
11/2016

SIMPARK SERIES

The Simpark series consists of shallow to a duripan, well drained soils that formed in residuum and colluvium derived from andesite, rhyolite, or quartzite. Simpark soils are on hills and mountains. Slopes are 2 to 50 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid, shallow Xeric Argidurids

TYPICAL PEDON: Simpark very cobbly loam--rangeland. (Colors are for dry soil unless otherwise noted.) The surface is partly covered with about 20 percent gravel and 40 percent cobbles.

A--0 to 8 cm; pale brown (10YR 6/3) very cobbly loam, dark brown (10YR 3/3) moist; moderate medium platy structure; slightly hard, very friable, slightly sticky and slightly plastic; common fine and medium roots; many very fine, fine, and medium vesicular pores; 10 percent gravel and 25 percent cobbles; slightly alkaline (pH 7.8); clear wavy boundary. (8 to 18 cm thick)

BA--8 to 33 cm; pale brown (10YR 6/3) gravelly loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine roots; common fine tubular pores; l5 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.8); clear wavy boundary. (0 to 28 cm thick)

Btq--33 to 46 cm; pale brown (10YR 6/3) very cobbly loam, brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; few fine and few medium roots; few fine tubular pores; common distinct clay films on faces of peds and bridging sand grains; 20 percent gravel and 15 percent cobbles; few fine coats of silica on bottoms of rock fragments; moderately alkaline (pH 8.2); clear wavy boundary. (8 to 38 cm thick)

Bqkm--46 to 56 cm; very pale brown (10YR 7/3) duripan, brown (10YR 5/3) moist; massive; extremely hard and extremely firm; indurated by secondary silica with 1.25 cm thick continuous laminar cap of opal and secondary carbonates; violently effervescent; clear wavy boundary. (5 to 28 cm thick)

R--56 cm; andesite.

TYPE LOCATION: Lander County, Nevada; about 21 miles southeast of Austin between the Toquima Range and Monitor Valley; in a nonsectionized township about 5.4 miles south and 2,200 feet east of the northwest corner of section 6, T. l8 N., R. 47 E.; USGS Potts Well 7.5 minute topographic quadrangle; latitude 39 degrees 21 minutes 30 seconds N and longitude 116 degrees 42 minutes 58 seconds W; WGS84 Decimal Degrees 39.3583333 latitude, -116.7158333 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry; moist in winter and spring, dry mid-June through mid-October; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Depth to base of argillic horizon: 36 to 50 cm.
Depth to duripan: 36 to 50 cm.
Depth to bedrock: 50 to 76 cm to a lithic contact.
Other features - Some pedons have thin Bk horizons above the duripan.

Particle-size control section - Clay content: 18 to 27 percent.
Rock fragments: 35 to 60 percent, mainly cobbles with some subhorizons having dominantly gravel. Lithology of fragments are andesite, rhyolite, or quartzite.

A horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Reaction: Neutral or slightly alkaline.

Btq horizon
Hue: 7.5YR or 10YR.
Value: 4 through 6 dry, 3 through 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Very cobbly loam or very gravelly loam.
Clay content: 18 to 27 percent.
Rock fragments: 35 to 60 percent.
Reaction: Slightly alkaline or moderately alkaline.
Salinity (EC): 0 to 2 mmhos/cm.

Bqkm horizon
Cementation: Very strongly cemented or indurated.

COMPETING SERIES: This is the Spiderhole series. Spiderhole soils average 10 to 18 percent clay in the particle-size control section.

GEOGRAPHIC SETTING: Simpark soils are on hills and mountains. These soils formed in residuum and colluvium derived from andesite, rhyolite, and quartzite with a component of volcanic ash. Slopes are 2 to 50 percent. Elevations range from 1,865 to 2,290 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 7 degrees C, and the frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Akerue, Punchbowl, and Robson soils. Akerue soils are clayey-skeletal. Punchbowl soils are loamy and shallow to lithic contacts. Robson soils are clayey-skeletal and shallow to lithic contacts.

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

USE AND VEGETATION: Simpark soils are used for livestock grazing and wildlife habitat. The present vegetation is mainly black sagebrush, Sandberg's bluegrass, low rabbitbrush, Thurber's needlegrass, and bottlebrush squirreltail.

DISTRIBUTION AND EXTENT: Central Nevada. These soils are moderately extensive. MLRA 28B.

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

SERIES ESTABLISHED: Eureka County, Nevada, 1983.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 33 cm (A and BA horizons).
Argillic horizon - The zone from 33 to 46 cm (Btq horizon).
Duripan - The zone from 46 to 56 cm (Bqkm horizon).
Lithic contact - The boundary at 56 cm to underlying hard bedrock (R layer).
Particle size control section - The zone from 33 to 46 cm (Btq horizon).

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National Cooperative Soil Survey
U.S.A.