LOCATION SUMEADOW CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic Xeric Humicryepts
TYPICAL PEDON: Sumeadow very gravelly peaty sandy loam--forest land. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with about 2 inches of undecomposed duff and 25 percent gravel, 5 percent cobbles, and 5 percent stones.
Oi--0 to 0.5 inch; very dark grayish brown (10YR 3/2) slightly decomposed plant material composed of fibrous needle litter, black (10YR 2/1) moist; strongly acid. (0 to 1 inch thick)
A1--0.5 to 2 inches; dark grayish brown (10YR 4/2) very gravelly peaty sandy loam, very dark brown (10YR 2/2) moist; moderate medium platy parting to weak fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine roots; common very fine interstitial pores; 25 percent gravel, 5 percent cobbles, and 5 percent stones; strongly acid; clear smooth boundary. (1 or 2 inches thick)
A2--2 to 13 inches; brown (10YR 4/3) extremely gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, and many fine, many medium, many coarse, and many very coarse roots; common very fine tubular and interstitial pores; 47 percent gravel, 10 percent cobbles, and 10 percent stones; strongly acid; clear wavy boundary. (6 to 12 inches thick)
Bw1--13 to 32 inches; yellowish brown (10YR 5/4) extremely gravelly coarse sandy loam, dark yellowish brown (10YR 3/4) moist; moderate fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, many fine, many medium, many coarse, and many very coarse roots; common very fine tubular and interstitial pores; 50 percent gravel, 20 percent cobbles, and 5 percent stones; strongly acid; clear wavy boundary. (12 to 22 inches thick)
Bw2--32 to 40 inches; yellowish brown (10YR 5/4) extremely gravelly coarse sandy loam, dark yellowish brown (10YR 3/4) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, many fine, many medium, many coarse, and many very coarse roots; common very fine and fine tubular and interstitial pores; 50 percent gravel, 20 percent cobbles, and 5 percent stones; strongly acid; clear wavy boundary. (6 to 12 inches thick)
Bw3--40 to 46 inches; yellowish brown (10YR 5/4) extremely gravelly sandy loam, dark yellowish brown (10YR 3/4) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine, common fine, common medium, and common coarse roots; common very fine tubular and interstitial pores; 60 percent gravel and 15 percent cobbles; strongly acid; clear wavy boundary. (0 to 10 inches thick)
BC--46 to 65 inches; yellowish brown (10YR 5/4) extremely gravelly sandy loam, dark yellowish brown (10YR 3/4) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine, common fine, common medium, common coarse, and common very coarse roots; common very fine tubular and interstitial pores; few fine faint brown (7.5YR 4/4) moist, irregular masses of iron accumulation; 55 percent gravel and 10 percent cobbles; strongly acid.
TYPE LOCATION: Mono County, California; on the Toiyabe National Forest about 1,500 feet south of Summit Meadow; approximately 1,200 feet north and 1,100 feet west of the southeast corner of section 35, T. 7 N., R. 22 E.; USGS Lost Cannon Peak 7.5 minute topographic quadrangle; 38 degrees 24 minutes 21.2 seconds north latitude and 119 degrees 31 minutes 23.7 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in the moisture control section during late fall, winter, and spring; dry from mid-July through September for 60 to 80 consecutive days in the four months following the summer solstice; Typic xeric moisture regime.
Mean annual soil temperature - 40 to 44 degrees F.
Mean summer soil temperature - 44 to 47 degrees F.
Umbric epipedon thickness - 10 to 16 inches.
Depth to base of cambic horizon - 35 to 50 inches.
Depth to bedrock - More than 80 inches.
Sodium fluoride pH - 10.0 to 11.5.
Particle-size control section - Clay content: Averages 10 to 18 percent; Rock fragments: Averages 60 to 80 percent, mainly gravel and cobbles. Lithology of fragments are andesite, tuff, or tuff breccia.
A1 horizon
Organic matter content: 10 to 18 percent.
Reaction: Strongly acid or moderately acid.
A2 horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 3 to 5 percent.
Reaction: Strongly acid or moderately acid.
Bw and BC horizons
Hue: 10YR or 2.5Y.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 3 or 4, dry or moist.
Texture: Extremely gravelly coarse sandy loam or extremely gravelly sandy loam.
Clay content: 10 to 18 percent.
Rock fragments: 60 to 80 percent.
Reaction: Strongly acid or moderately acid.
COMPETING SERIES: These are the Callat (T), Fishsnooze, Florand, Forsell, Lostridge, Sibelia, and Sonorapass series.
Callat soils are moderately deep to densic contacts. Fishsnooze and Sonorapass soils are moderately deep to lithic contacts. Florand and Sibelia soils are deep to paralithic contacts. Forsell soils have a lithic contact between 60 and 80 inches from the soil surface, have horizons dominated by stones, and have rock fragments of granitic lithology in the particle-size control section. Lostridge soils are moderately deep to paralithic contacts.
GEOGRAPHIC SETTING: Sumeadow soils are on mountains. They typically occur on footslope and backslope positions. They formed in colluvium derived from andesite, tuff, and tuff breccia. Slopes are 4 to 50 percent. Elevations range from 8,000 to 10,000 feet. The climate is subhumid-continental with cold, moist winters and cool, dry summers. The mean annual precipitation is 25 to 35 inches, mean annual temperature is 36 to 39 degrees F., and the frost-free period is 30 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Hawkinspeak and Hawkridge soils. Hawkinspeak soils have mollic epipedons, argillic horizons, and are moderately deep to lithic contacts. Hawkridge soils have mollic epipedons, argillic horizons, and are shallow to lithic contacts.
DRAINAGE AND PERMEABILITY: Well drained; low or medium surface runoff; moderately rapid permeability (high saturated hydraulic conductivity).
USE AND VEGETATION: Sumeadow soils are used for forest land, recreation, watershed, and wildlife habitat. The native vegetation is a forest canopy of mainly lodgepole pine with scattered western white pine, limber pine, and whitebark pine and an understory of currant and sedges.
DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are not extensive with about 6,900 acres of the series mapped to date. MLRA 22A.
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:
Organic soil material - The zone from the soil surface to 0.5 inch (Oi horizon).
Umbric epipedon - The zone from 0.5 to 13 inches (A1 and A2 horizons).
Cambic horizon - The zone from 13 to 46 inches (Bw1, Bw2, and Bw3 horizons).
Particle-size control section - The zone from 10 to 40 inches (Bw1 and Bw2 horizons and part of the A2 horizon).
The revision of December 2006 updated the taxonomic class from Xeric Dystrocryepts based on the tenth edition of the Keys to Soil Taxonomy, 2006.
The isotic mineralogy class is based on the field determined values for sodium fluoride pH.