LOCATION HORROCKS UTEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Argixerolls
TYPICAL PEDON: Horrocks very cobbly sandy clay loam--rangeland. (Colors are for air-dry soil unless otherwise stated.)
A--0 to 5 inches; very dark grayish brown (10YR 3/2) very cobbly sandy clay loam, very dark brown (10YR 2/2) moist; weak medium granular structure; soft, very friable, slightly sticky and slightly plastic; common fine roots; 25 percent gravel, 20 percent cobbles; neutral (pH 6.8); clear wavy boundary. (5 to 18 inches thick)
Bt1--5 to 14 inches; dark grayish brown (10YR 4/2) very cobbly sandy clay loam, very dark grayish brown (10YR 3/2) moist; weak coarse subangular blocky structure parting to moderate fine subangular blocky; slightly hard, friable, sticky and plastic; common fine, medium and large roots; few fine pores; common faint clay films; 15 percent gravel, 25 percent cobbles, and 15 percent stones; neutral (pH 6.6); clear irregular boundary. (0 to 10 inches thick)
Bt2--14 to 27 inches; brown (10YR 4/3) extremely cobbly sandy clay loam, dark yellowish brown (10YR 3/4) moist; weak coarse subangular blocky structure parting to moderate fine subangular blocky; hard, firm, sticky and plastic; common fine and medium roots; few fine pores; distinct continuous clay films; 20 percent gravel, 70 percent cobbles, 15 percent stones; slightly acid (pH 6.3); clear irregular boundary. (8 to 15 inches thick)
C--27 to 41 inches; pale brown (10YR 6/3) extremely cobbly sandy loam, dark grayish brown (10YR 4/2) moist; massive; loose, very friable, slightly sticky and slightly plastic; common fine and medium roots; 20 percent gravel, 30 percent cobbles, and 15 percent stones; slightly acid (pH 6.4); clear irregular boundary. (12 to 36 inches thick)
R--41 inches; bedrock.
TYPE LOCATION: Wasatch County, Utah; about 15 miles southwest of Heber; at a point at the south end of Deer Creek Reservoir, 1.9 miles east along side road; 2,575 feet south and 940 feet east of northwest corner of sec. 32, T. 4 S., R. 4 E.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 10 to 20 inches thick. The soil has either moist value of 4 or contains less than 1 percent organic matter below a depth of 20 inches. The combined thickness of the A and Bt horizons ranges from 14 to 40 inches. Bedrock is encountered at variable depths below 40 inches. Rock fragments are mainly cobble and gravel size rounded or angular andesite, quartzite or sandstone fragments; ranging from 20 to 70 percent in the A horizon and 35 to 80 percent in the Bt and C horizons. The mean annual soil temperature ranges from 37 to 47 degrees F., and the mean summer soil temperature at a depth of about 20 inches ranges from 60 to 66 degrees F. The soils are usually moist but are dry in all parts of the 8 to 24 inch depth for 45 or more consecutive days in 6 or more years out of 10.
The A horizon has hue of 10YR or 7.5YR, value of 3 to 5 dry, 2 or 3 moist, and chroma of 2 or 3. This horizon is neutral to moderately acid.
The Bt horizon has hue of 10YR to 5YR, value of 3 to 6 dry, 2 to 4 moist, and chroma of 2 to 6. The texture ranges from very gravelly or very cobbly sandy clay loam or clay loam to extremely gravelly or extremely cobbly loam. It has moderately thick continuous to few thin clay films. This horizon has weak to moderate, fine to coarse angular or subangular blocky structure. It ranges from neutral to moderately acid.
The C horizon has hue of 10YR to 5YR, value of 4 to 7 dry, 3 to 5 moist, and chroma of 3 to 6. It is very cobbly sandy loam, very cobbly loam, very gravelly loam, very gravelly sandy clay loam. This horizon ranges from slightly acid to moderately alkaline.
COMPETING SERIES: These are the Clanalpine (NV), Heechee (NV), Holmes, Hoskin, Howcan T(ID), Pequop (NV), Snyderville (T UT), Squawtip (NV), Suak (NV), Valmar (ID), Vitale (ID) and Wambolt (NV) series.Clanalpine and Squawtip soils have a paralithic contact at depths of 20 to 40 inches.Heechee soils have a discontinuity in the argillic horizon. Holmes soils have very gravelly loam or very gravelly sandy loam weak argillic horizons and have very gravelly and cobbly loamy sand or sandy loam C horizons at depths of less than 40 inches.Hoskin, Valmar and Vitale soils have bedrock at a depth of 20 to 40 inches. Howcan soils are dry more than 60 consecutive days and the combined thickness of the A and B horizons is greater than 40 inches.Pequop soils are mostly gravel in the argillic horizon and have solum thickness greater than 40 inches.Snyderville and Wambolt soils have bedrock at 60 inches or more.
GEOGRAPHIC SETTING: Horrocks soils are on moderately sloping to very steep dominantly south and west facing mountain slopes and terminal moraines at elevations of 5,300 to 8,400 feet. Slopes range from 5 to 70 percent. These soils formed in glacial deposits, residuum, alluvium and colluvium from andesite and some conglomerate, sandstone, limestone and quartzite. The climate is moist subhumid with warm dry summers and cold moist winters. The average annual precipitation is 16 to 27 inches falling mostly as snow. The mean annual air temperature ranges from 35 to 45 degrees F., and the mean summer temperature ranges from 60 to 63 degrees F. Freeze-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Broadhead, Condie, Geertsen, Henefer, Little Pole and Yeates Hollow soils. Broadhead and Henefer soils have clay argillic horizons that contain less than 35 percent rock fragments. Condie soils lack a mollic epipedon. Geertsen soils have mean summer temperature less than 59 degrees F. Little Pole soils are 10 to 20 inches deep over bedrock. Yeates Hollow soils contains more than 35 percent clay in the fine particle-size control section.
DRAINAGE AND PERMEABILITY: Well to somewhat excessively drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used mainly as watershed and spring to fall grazing for livestock and wildlife. Native vegetation is bluebunch wheatgrass, bitterbrush, tall native bluegrass, prairie junegrass, slender wheatgrass, oniongrass, basin wildrye, balsamroot, buckwheat, herbaceous sage, big sagebrush, serviceberry, snowberry, and oakbrush.
DISTRIBUTION AND EXTENT: Mountain areas in northern Utah. This series is moderately extensive. MLRA 47.
MLRA OFFICE RESPONSIBLE: Lakewood, Colorado
SERIES ESTABLISHED: Heber Valley Area, Utah, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 14 inches. (A, Bt1 horizons)
Argillic horizon - from 5 to 27 inches. (Bt1, Bt2 horizons)
Particle-size control section - the zone from 5 to 25 inches.
Classification: Keys to Soil Taxonomy, Eighth Edition, 1998.