LOCATION LOOPE                   CA

Established Series
Rev. EWB-JVC-JBF
03/2017

LOOPE SERIES


The Loope series consists of shallow, well drained soils that formed in colluvium and residuum derived from tuff, tuff-breccia, and andesite. Loope soils are on mountains. Slopes are 4 to 75 percent. The mean annual precipitation is about 510 mm and the mean annual temperature is about 6 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Argixerolls

TYPICAL PEDON: Loope very gravelly sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 30 percent gravel, 5 percent cobbles, and less than 1 percent stones.

A--0 to 3 cm; brown (7.5YR 5/2) very gravelly sandy loam, dark brown (7.5YR 3/3) moist; weak fine granular structure; soft, very friable, slightly sticky and nonplastic; common very fine roots; common very fine tubular and interstitial pores; 50 percent gravel; neutral (pH 6.7); clear smooth boundary. (3 to 9 cm thick)

Bt1--3 to 18 cm; brown (7.5YR 5/3) extremely gravelly sandy loam, dark brown (7.5YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; common very fine tubular and interstitial pores; few faint clay bridges between sand grains; 70 percent gravel and 5 percent cobbles; neutral (pH 6.8); clear wavy boundary. (8 to 18 cm thick)

Bt2--18 to 36 cm; brown (7.5YR 5/3) extremely gravelly sandy clay loam, dark brown (7.5YR 3/3) moist; weak fine subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine through very coarse roots; common very fine tubular and interstitial pores; common faint clay bridges between sand grains; 70 percent gravel and 5 percent cobbles; neutral (pH 6.8); abrupt irregular boundary. (15 to 25 cm thick)

R--36 cm; hard fractured tuff.

TYPE LOCATION: Alpine County, California; on the Toiyabe National Forest about 0.4 mile northeast of Colorado Hill; approximately 1,150 feet south and 1,350 feet east of the northwest corner of section 32, T. 10 N., R. 21 E.; USGS Heenan Lake 7.5 minute topographic quadrangle; latitude 38 degrees 40 minutes 24.4 seconds N and longitude 119 degrees 41 minutes 57.6 seconds W; WGS84 Decimal Degrees 38.6734444 latitude, -119.6993333 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 to 8 degrees C.
Mean summer soil temperature: 17 to 19 degrees C.
Mollic epipedon thickness: 36 to 50 cm; includes the Bt horizons.
Depth to bedrock: 36 to 50 cm to lithic contact.
Sodium fluoride pH: 8.5 to 9.0.

Particle-size control section - Clay content: Averages 18 to 27 percent. Rock fragments: Averages 60 to 80 percent, mainly gravel. Lithology of fragments are volcanic rocks such as tuff, tuff-breccia, or andesite.

A horizon
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 2 to 4 percent.
Reaction: Slightly acid or neutral.

Bt horizons
Hue: 10YR or 7.5YR.
Chroma: 2 or 3, dry or moist.
Texture: Extremely gravelly sandy loam, extremely gravelly sandy clay loam, or extremely gravelly 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.

COMPETING SERIES: These are the Anaud, Bellenmine, Celeridge, Cleavage, Cleavmor, Cropper, Gabica, Gaciba, Genoa, Gerdog, Gidwin, Grandeposit, Granquin, Grosschat, Hawkridge, Hutchley, Mascamp, Melling, Pernog, Pernty, Rozara, Shalcleav, Shalper, Slatter, Tractuff, and Tweener series.

Anaud, Bellenmine, Cleavage, Cleavmor, Cropper, Gaciba, Grosschat, Mascamp, Pernty, Shalper, Slatter, Tractuff, and Tweener soils have an aridic moisture regime. Celeridge soils have 5 to 8 percent organic matter in the A horizons and have mean summer soil temperatures of 15 to 17 degrees C. Gabica soils average 35 to 60 percent rock fragments in the particle-size control section and have 1 or 2 percent organic matter in the mollic epipedon. Genoa soils are dominated by cobbles in the particle-size control section and have rock fragments that are granitic rocks. Gerdog and Hawkridge soils have lithic contacts at depths of 18 to 36 cm. Gidwin soils are influenced by loess, have rock fragments that are basalt, and have frost-free periods of 70 to 110 days. Grandeposit and Granquin soils have 27to 35 percent clay in the particle size control section. Hutchley soils have subhorizons of the argillic horizon with 28 to 35 percent clay. Melling soils average 35 to 60 percent rock fragments in the particle-size control section and are dry for 45 to 60 consecutive days in the four months following the summer solstice. Pernog soils are dominated by stones and have more than 27 percent clay in some part of the particle-size control section. Rozara soils are dominated by fine gravel, have rock fragments that are granitic rocks, have 14 to 18 percent clay, and average 45 to 60 percent rock fragments in the particle-size control section. Shalcleav soils are dominated by channers and flagstones and have lithic contacts at depths of 10 to 30 cm.

GEOGRAPHIC SETTING: Loope soils are on mountains. They typically occur on backslope positions. They formed in colluvium and residuum derived from tuff, tuff-breccia, and andesite. Slopes are 4 to 75 percent. Elevations range from 1,620 to 2,655 meters. The climate is subhumid-continental with cold, moist winters and warm, dry summers. The mean annual precipitation is 360 to 610 mm, mean annual temperature is 4 to 7 degrees C., and the frost-free period is 40 to 70 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Carshal, Chenhigh, and Heenlake soils. Carshal soils have ochric epipedons and do not have argillic horizons. Chenhigh soils are clayey-skeletal. Heenlake soils are moderately deep to paralithic contacts.

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

USE AND VEGETATION: Loope soils are used for livestock grazing, recreation, watershed, and wildlife habitat. The native vegetation is mainly mountain big sagebrush, antelope bitterbrush, and western needlegrass with scattered singleleaf pinyon, Jeffrey pine, and Sierra juniper.

DISTRIBUTION AND EXTENT: Eastern California, on the east side of the Sierra Nevada Range. These soils are moderately extensive. MLRAs 22A and 26.

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

SERIES ESTABLISHED: Alpine 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 36 cm (A, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 3 to 36 cm (Bt1 and Bt2 horizons).
Lithic contact - The boundary at 36 cm to underlying hard bedrock (R layer).
Particle-size control section - The zone from 3 to 36 cm (Bt1 and Bt2 horizons).

The revision of October 2003 updated the taxonomic class from Loamy-skeletal, isotic, frigid Lithic Argixerolls. The isotic mineralogy class was based solely on the field determined values for sodium fluoride pH. Laboratory data on 15 bar water to clay ratio does not exist to verify the isotic mineralogy class.


National Cooperative Soil Survey
U.S.A.