LOCATION BIRCHCREEK              ID+NV

Established Series
Rev. FRK-CLM-JVC-JBF
09/2018

BIRCHCREEK SERIES

The Birchcreek series consists of moderately deep, well drained soils that formed in alluvium, colluvium, and residuum derived from mica schist and quartzite or from andesite. Birchcreek soils are on mountains. Slopes are 4 to 55 percent. The mean annual precipitation is about 360 mm and the mean annual temperature is about 5.6 degrees C.

TAXONOMIC CLASS: Clayey-skeletal, smectitic, frigid Typic Argixerolls

TYPICAL PEDON: Birchcreek very stony loam--on a 47 percent north-facing, simple slope at 1,925 meters elevation--rangeland. (Colors are for dry soil unless otherwise noted. When described on June 12, 1986, the soil was dry from the surface to a depth of 3 cm and was moist below.) The soil surface has class 4 cover with stones.

A--0 to 8 cm; dark grayish brown (10YR 4/2) very stony loam, black (10YR 2/1) moist; weak thick platy structure parting to moderate fine and medium granular; soft, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular pores; 20 percent stones, 20 percent cobbles, and 15 percent gravel; neutral (pH 6.8); clear smooth boundary. (8 to 25 cm thick)

Bt1--8 to 18 cm; dark grayish brown (10YR 4/2) very cobbly clay loam, black (10YR 2/1) moist; moderate very fine and fine subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine roots; many very fine and few fine tubular pores; few faint clay films on faces of peds and lining pores; 30 percent cobbles and 20 percent gravel; neutral (pH 6.8); clear wavy boundary. (5 to 20 cm thick)

Bt2--18 to 33 cm; brown (10YR 5/3) very cobbly clay loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine and few medium roots; many very fine and few fine tubular pores; few faint clay films on faces of peds and lining pores; 35 percent cobbles and 20 percent gravel; neutral (pH 6.8); clear wavy boundary. (8 to 33 cm thick)

Bt3--33 to 58 cm; yellowish brown (10YR 5/6) very stony clay, dark yellowish brown (10YR 4/4) moist; moderate fine subangular blocky structure; hard, very friable, very sticky and very plastic; few very fine and medium roots; many very fine and few fine tubular pores; common faint clay bridges; 20 percent stones, 20 percent cobbles, and 10 percent gravel; neutral (pH 7.3); abrupt wavy boundary. (0 to 40 cm thick)

R--58 cm; unweathered quartzite bedrock.

TYPE LOCATION: Cassia County, Idaho; about 6 miles south of Oakley, Idaho; about 750 feet west and 525 feet north of the southeast corner of section 21, T. 15 S., R. 22 E.; USGS Blue Hill 7.5 minute quadrangle; latitude 42 degrees 06 minutes 0 seconds N and longitude 113 degrees 52 minutes 31 seconds W; WGS84 Decimal Degrees 42.1000000 latitude, -113.8752778 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section in winter and spring, dry in summer and fall; xeric moisture regime that borders on aridic.
Mean annual soil temperature: 6 to 8 degrees C.
Mollic epipedon thickness: 25 to 46 cm; includes the Bt1 and Bt2 horizons.
Depth to bedrock: 50 to 100 cm to a lithic contact.
Reaction: Neutral or slightly alkaline.

Particle-size control section - Clay content: Averages 40 to 50 percent.
Rock fragments: 45 to 60 percent, mainly cobbles and gravel in the upper part and cobbles and stones in the lower part. Lithology of fragments is metamorphic rocks such as mica schist and quartzite or volcanic rock such as andesite.

A horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 1 through 3, dry or moist.
Clay content: 15 to 25 percent.
Organic matter content: 1 to 3 percent.

Bt1 and Bt2 horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 through 4 dry, 1 through 3 moist.

Clay content: 28 to 40 percent.
Rock fragments: 25 to 40 percent mainly cobbles with 15 to 40 percent gravel.
Texture modifiers: Averages very cobbly; some pedons contain sub-horizons that are very stony.
Organic matter content: 1 or 2 percent.

Bt3 horizon
Value: 4 or 5 dry, 2 through 4 moist.
Chroma: 2 through 6, dry or moist.
Clay content: 40 to 55 percent.
Rock fragments: 25 to 40 percent cobbles and stones; 15 to 40 percent gravel.
Texture modifiers: Averages very stony; some pedons contain sub-horizons that are very cobbly.

COMPETING SERIES: These are the Derringer, Droem, Leevan, McIvey, Ravenswood, Roostercomb, Sharesnout, Threek, Tickville, Urwil, Wilpar, Yago, and Yeates Hollow series.

Derringer soils are moderately deep to paralithic contacts. Droem soils average less than 40 percent clay in the particle-size control section. Leevan and Ravenswood soils are dominated by gravel in the particle-size control section. Leevan and Roostercomb soils do not include the upper part of the argillic horizon in the mollic epipedon. McIvey, Threek, Urwil, and Yago soils are very deep. Sharesnout soils have less than 25 percent rock fragments larger than 8 cm in the particle-size control section. Tickville soils have a typic xeric moisture regime. Wilpar soils are deep to paralithic contacts. Yeates Hollow soils are deep to lithic contacts.

GEOGRAPHIC SETTING: Birchcreek soils are on mountains. They typically occur on backslope positions. These soils formed in alluvium, colluvium, and residuum derived from mica schist and quartzite or from andesite. Slopes are 4 to 55 percent. Elevation ranges from 1,710 to 2,140 meters in Idaho and ranges to 2,440 meters in Nevada. The mean annual precipitation is 300 to 400 mm, the mean annual temperature is 5 to 7 degrees C, and the frost-free period is 75 to 95 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Acord, Hutchley, and Itca soils, and the competing Yeates Hollow soil. Acord soils are very deep, have Bk horizons, and are on fan remnants. Hutchley and Itca soils are shallow to lithic contacts, are on mountains, and commonly occur on slightly convex backslope positions or on summit positions.

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

USE AND VEGETATION: Birchcreek soils are used for livestock grazing. The vegetation is mountain big sagebrush, low sagebrush, bluebunch wheatgrass, and Idaho fescue. Some areas support stands of singleleaf pinyon and Utah juniper.

DISTRIBUTION AND EXTENT: Southern Idaho and eastern Nevada. These soils are moderately extensive. The original series concept is in MLRA 25 in Idaho, while the main acreage occurs in MLRA 28B in Nevada.

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

SERIES ESTABLISHED: Cassia County, Idaho, 1986.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 33 cm (A, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 8 to 58 cm (Bt1, Bt2, and Bt3 horizons).
Lithic contact - The boundary at 58 cm to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 8 to 58 cm (Bt1, Bt2, and Bt3 horizons).

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National Cooperative Soil Survey
U.S.A.