LOCATION PERINOS UTTentative Series
TAXONOMIC CLASS: Fine, smectitic Pachic Argicryolls
TYPICAL PEDON: Perinos stony loam - rangeland. (Colors are for moist soil unless otherwise noted.)
A1--0 to 15 inches; black (10YR 2/1) stony loam, very dark grayish brown (10YR 3/2) dry; .moderate fine granular structure; hard, friable, slightly sticky and slightly plastic; common fine and few medium roots; common very fine and few medium tubular pores; 5 percent gravel and 5 percent stones; neutral (pH 6.8); clear smooth boundary. (1 to 15 inches thick)
A2--15 to 21 inches; very dark brown (10YR 2/2) loam, very dark grayish brown (10YR 3/2) dry; moderate coarse angular blocky structure; very hard, friable, slightly sticky and plastic; few fine and medium roots; common fine and few medium tubular pores; 5 percent gravel; neutral (pH 6.8); clear wavy boundary. (6 to 8 inches thick)
Bt1--21 to 37 inches; reddish brown (2.5YR 4/4) clay, reddish brown (2.5YR 5/4) dry; strong medium and prismatic structure; extremely hard, firm, sticky and plastic; few fine roots; few fine tubular pores; moderately thick continuous clay films; organic stains on top of prisms; about 2 percent cobbles and about 2 percent gravel; neutral (pH 6.8); clear wavy boundary. (4 to 16 inches thick)
Bt2--37 to 46 inches; reddish brown (5YR 4/4) clay, light reddish brown (5YR 6/4) dry; moderate coarse angular blocky structure; extremely hard, firm, sticky and plastic; few fine roots; few fine tubular pores; moderately thick continuous clay films; about 2 percent cobbles and about 2 percent gravel; neutral (pH 7.0); gradual wavy boundary. (7 to 17 inches thick)
C1--46 to 52 inches; dark grayish brown (lOYR 4/2) clay loam, grayish brown (10YR 5/2) dry; strong medium prismatic structure; extremely hard, firm, sticky and plastic; few fine roots; few fine tubular pores; 10 percent cobbles and 5 percent gravel; neutral (pH 7.0); gradual wavy boundary. (6 to 10 inches thick)
C2--52 to 60 inches; dark brown (7.5YR 4/2) gravelly clay, brown (7.5YR 5/2) dry; massive; extremely hard, firm, sticky and plastic; 10 percent cobbles and 10 percent Gravel; matrix is noncalcareous but contains lime flecks that are moderately calcareous; neutral (pH 7.2).
TYPE LOCATION: Sevier County, Utah; 3.3 miles southeast of Rex Reservoir; 50 feet south of jeep trail in SW1/4 of SE1/4 of NW1/4 section 5, T. 24 S., R. 2 E., SLM.
RANGE IN CHARACTERISTICS: The mollic epipedon is 16 to 27 inches thick. The solum is 40 to 60 inches thick. The mean annual soil temperature at depth of 20 inches ranges from 38 to 40 degrees F. The mean summer soil temperature is 52 to 55 degrees F.
The A horizon has chroma of 1 or 2 dry and moist. It is stony loam, cobbly loam or clay loam with 0 to 20 percent rock fragments of which up to 10 percent are stones. It is neutral or mildly alkaline and is 9 to 23 inches thick.
The Bt horizon has hue of 2.5YR or 5YR, value of 4 through 6 dry, 3 through 5 moist and chroma of 2 through 4 dry and moist. It is clay or clay loam and has 35 to 50 percent clay and 0 to 5 percent rock fragments. It is neutral or mildly alkaline and is 14 to 33 inches thick.
The C horizon has hue of 5YR through 10YR, value of 3 through 6 dry, 3 through 5 moist, and chroma of 2 through 4 dry and moist. It is clay, gravelly clay, clay loam or sandy clay loam and has O to 20 percent rock fragments. This horizon is neutral or mildly alkaline.
COMPETING SERIES: These are the Burnette (MT), Cochetopa (CO), Faim, Friana (AZ), Fulcher (CO), Grouseville T(ID), Luna (AZ), Mayflower (CO), Paulson (WY), Richens, Runlett T(CO), Skutum, Slights T(ID, Sudduth (CO), Sudpeak (ID), Teedown T(CO), and Toponce (ID) series. Burnette, Cochetopa, Faim, Fulcher, Grouseville, Luna, Slights, Sudduth, Sudpeak, and Teedown soils have hue of 7.5YR or yellower in the argillic horizon. Burnette soils have a calcic horizon. Cochetopa soils have more than 15 percent rock fragments in the control section. Fulcher soils have an accumulation of carbonate at depths of 17 to 50 inches. Luna soils have an A1 horizon less than 6 inches thick and are 20 to 40 inches deep over decomposing ash or tuff. Friana soils are mottled in the lower part of the argillic horizon with black coatings that effervesce with hydrogen peroxide. Mayflower and Runlett soils are 20 to 40 inches deep over bedrock. Paulson soils have an A1 horizon 4 to 8 inches thick and have a silty clay argillic horizon. Richens soils have an A2 horizon and have a argillic horizon that is medium acid or slightly acid and has a chroma of 6 or more. Skutum soils have a gravelly argillic horizon with 15 to 35 percent gravel. Slights soils have boulders throughout the profile and have a lithologic discontinuity that separates the upper and lower part of the B2t horizon. Sudpeak soils have a Bg (gleyed) horizon and are moderately well drained. Toponce soils have a combined thickness of the A and B horizons that is greater than 60 inches and the particle size control section is moderately to slightly acid.
GEOGRAPHIC SETTING: Perinos soils are at elevations of 8,300 to 9,000 feet. They occur on mountain slopes, and formed in material weathered from basic igneous rocks. Slopes are 3 to 60 percent. The climate is humid. The average annual precipitation is 22 to 30 inches. The mean annual air temperature is 35 to 38 degrees F., and the freeze-free season is 55 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Acord, Henefer, Lizzant and Vicking soils. Acord, Lizzant and Vicking soils have a mollic epipedon less than 20 inches thick and have a calcic horizon. Acord soils contain more than 35 percent rock fragments in the control section. Lizzant soils have carbonatic mineralogy and lack argillic horizons. Acord, Henefer, Lizzant and Vicking soils have a mean summer temperature that exceeds 59 degrees F.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; slow permeability.
USE AND VEGETATION: These soils are used for range. The native vegetation is aspen, snowberry, Kentucky bluegrass and mountain brome and slender wheatgrass.
DISTRIBUTION AND EXTENT: Central Utah, Lost Creek Area in Sevier County; MLRA 47. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES PROPOSED: Loa-Richfield Area, Sevier County, 1975.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 21 inches (A1, A2 horizons).
Pachic feature - the mollic thicker than 16 inches.
Argillic horizon - the zone from 21 to 46 inches (Bt1, Bt2 horizons).
Particle size control section - the zone from 21 to 41 inches.