LOCATION BURCHFLAT CA
Established Series
Rev. EWB-JVC
02/2017
BURCHFLAT SERIES
The Burchflat series consists of moderately deep, well drained soils that formed in residuum and colluvium derived from andesite, tuff, or tuff breccia. Burchflat soils are on mountains. Slopes are 4 to 50 percent. The mean annual precipitation is about 500 mm and the mean annual temperature is about 5.6 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Pachic Argixerolls
TYPICAL PEDON: Burchflat very gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 25 percent gravel, 5 percent cobbles, and 2 percent stones.
A1--0 to 8 cm; grayish brown (10YR 5/2) very gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and nonplastic; many very fine roots; many very fine interstitial pores; 40 percent gravel and 5 percent cobbles; neutral (pH 6.7); clear wavy boundary. (3 to 13 cm thick)
A2--8 to 23 cm; grayish brown (10YR 5/2) extremely gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots; many very fine interstitial and common very fine tubular pores; 50 percent gravel and 10 percent cobbles; neutral (pH 6.7); clear wavy boundary. (13 to 25 cm thick)
Bt--23 to 53 cm; brown (10YR 5/3) extremely gravelly loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine, fine, medium and coarse roots; common very fine tubular and interstitial pores; common faint clay films on faces of peds and lining pores; 55 percent gravel and 10 percent cobbles; neutral (pH 6.8); clear wavy boundary. (18 to 41 cm thick)
2Bt--53 to 91 cm; pale brown (10YR 6/3) extremely stony loam, brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; few very fine and fine roots; common very fine tubular and interstitial pores; common faint clay films on faces of peds and lining pores; 50 percent gravel, 20 percent cobbles, and 15 percent stones; neutral (pH 6.8); clear irregular boundary. (18 to 46 cm thick)
2R--91 cm; hard andesitic tuff-breccia.
TYPE LOCATION: Mono County, California; on the Toiyabe National Forest west of the Sweetwater Mountains and about 1.75 miles northeast of Burcham Flat; approximately 1,000 feet north and 500 feet west of the southeast corner of section 35, T. 7 N., R. 23 E.; USGS Chris Flat 7.5 minute topographic quadrangle; 38 degrees 24 minutes 17.0 seconds north latitude and 119 degrees 24 minutes 50.1 seconds west longitude; WGS84 Decimal Degrees 38.4047222 latitude, -119.4139167 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in the moisture control section during late fall, winter, and spring; dry from July through early October for 75 to 90 consecutive days in the four months following the summer solstice; xeric moisture regime that borders on aridic.
Mean annual soil temperature: 6.7 to 8.3 degrees C.
Mollic epipedon thickness: 50 to 75 cm; includes the Bt1 horizon.
Depth to base of argillic horizon: 50 to 100 cm.
Depth to bedrock: 50 to 100 to a lithic contact.
Particle-size control section - Clay content: Averages 18 to 27 percent.
Rock fragments: Averages 60 to 80 percent, mainly gravel and cobbles. Lithology of fragments are volcanic rocks such as andesite, tuff, or tuff-breccia.
A horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 3 to 5 percent.
Reaction: Slightly acid or neutral.
Bt horizon
Chroma: 2 or 3 dry or moist.
Texture: Extremely gravelly loam or extremely gravelly sandy clay loam.
Clay content: 18 to 27 percent.
Rock fragments: 60 to 80 percent.
Organic matter content: 1 to 3 percent
Reaction: Slightly acid or neutral.
2Bt horizon
Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture: Extremely gravelly loam, extremely cobbly loam, or extremely gravelly sandy clay loam.
Clay content: 18 to 27 percent.
Rock fragments: 60 to 80 percent.
Reaction: Slightly acid or neutral.
COMPETING SERIES: These are the
Bullump,
Bullvaro,
Camelback,
Chrisflat,
Demner,
Dogbed,
Dooh,
Erig,
Krenka,
Leroman,
Lockgate,
Murain,
Nutval,
Snyderville,
Softback,
Softscrabble,
Staberg,
Vetagrande, and
Vipont series.
Bullump and
Camelback soils have lithic contacts between 100 and 200 cm from the soil surface.
Bullvaro,
Demner,
Dooh,
Nutval, and
Vetagrande soils have an aridic moisture regime.
Chrisflat,
Dogbed,
Krenka,
Murain,
Snyderville,
Softback, and
Softscrabble soils are very deep.
Erig soils are deep to lithic contacts.
Leroman and
Staberg soils are moderately deep to paralithic contacts.
Lockgate soils are deep to paralithic contacts.
Vipont soils have rock fragments of sandstone, quartzite, or mica schist.
GEOGRAPHIC SETTING: Burchflat soils are on mountains. They typically occur on summit or shoulder positions. They formed in residuum and colluvium derived from andesite, tuff, and tuff-breccia. Slopes are 4 to 50 percent. Elevations range from 2,135 to 2,535 meters. The climate is subhumid-continental with cold, moist winters and warm, dry summers. The mean annual precipitation is 410 to 610 mm, the mean annual temperature is 3.9 to 7.2 degrees C., and the frost-free period is 40 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Gerdog and
Loope soils and the competing
Murain soil. Gerdog and Loope soils are shallow to lithic contacts.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; moderately slow permeability; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Burchflat soils are used for rangeland, recreation, watershed, and wildlife habitat. The native vegetation is mainly mountain big sagebrush, antelope bitterbrush, snowberry, and western needlegrass.
DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are moderately extensive. MLRA 26.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Mono County (Toiyabe National Forest Area), California, 2006.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 53 cm (A1, A2, and Bt horizons).
Argillic horizon - The zone from 23 to 91 cm (Bt and 2Bt horizons).
Lithic contact - The boundary at 91 cm to underlying hard bedrock (2R layer).
Particle-size control section - The zone from 23 to 73 cm (Bt horizon and part of the 2Bt2 horizon).
National Cooperative Soil Survey
U.S.A.