LOCATION SEDWELL UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, carbonatic, frigid Pachic
Calcixerolls
TYPICAL PEDON: Sedwell silt loam, rangeland. (Colors are for air dry soil unless otherwise noted.)
All--0 to 3 inches; dark brown (10YR 3/3) silt loam, very dark brown (10YR 2/2) moist; weak thin platy structure that parts to weak fine granules; slightly hard, friable, slightly sticky, slightly plastic; many very fine and few fine roots; few fine pores; slightly calcareous, lime is disseminated; neutral (pH 7.3); clear smooth boundary. (2 to 6 inches thick)
A12--3 to 13 inches; dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; weak medium subangular blocky structure; slightly hard, firm, sticky, plastic; few very fine and few fine roots; few very fine and few fine pores; strongly calcareous, lime is disseminated and in fine soft limestone fragments; mildly alkaline (pH 7.4); gradual smooth boundary. (9 to 12 inches thick)
A13--13 to 22 inches; dark grayish brown (10YR 4/2) light silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; hard, firm, sticky, plastic; few very fine and few fine roots; few fine pores; 15 percent gravel and cobble; strongly calcareous, lime is disseminated, in veins and in fine soft limestone fragments; mildly alkaline (pH 7.8); gradual smooth boundary. (9 to 12 inches thick)
Clca--22 to 29 inches; grayish brown (10YR 5/2) cobbly silty clay loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; hard, firm, sticky, plastic; few very fine and few fine roots; few fine pores; 25 percent cobble and gravel; strongly calcareous lime is disseminated, in veins and in soft limestone fragments; mildly alkaline (pH 7.6); gradual wavy boundary. (6 to 10 inches thick)
C2ca--29 to 42 inches; grayish brown (10YR 5/2) cobbly silty clay loam, dark grayish brown (10YR 4/2) moist; massive; slightly hard, firm, sticky, plastic; few fine and few medium roots; few fine pores; 30 percent cobble and gravel; very strongly calcareous, lime is disseminated, in veins, and in fine soft limestone and shale fragments; moderately alkaline (pH 8.0); abrupt wavy boundary. (10 to 13 inches thick)
C3ca--42 to 47 inches; white (10YR 8/2) very shaly silt loam, pale yellow (2.5Y 7/3) moist; moderate medium platy structure; hard, firm, sticky, plastic; few very fine roots;, matted along shale plates; 70 percent soft weathering shale; very strongly calcareous, lime is disseminated and in shale fragments; mildly alkaline (pH 7.8); gradual wavy boundary. (4 to 7 inches thick)
C4--47 inches; Soft shale.
TYPE LOCATION: Sanpete County, Utah; 4 miles east of Mt. Pleasant near the junction of the power line and the jeep road; about 1,200 feet north and 2,500 feet east of the S. W. corner of sec. 8, T.15S., R.5E.
RANGE IN CHARACTERISTICS: The mollic epipedon is 20 to 30 inches thick. Depth to interbedded shale and limestone ranges from 40 to 60 inches. Calcium carbonate equivalent between depth of 10 and 40 inches averages more than 40 percent, including the lime in the coarse fragments of less than 20 mm. size. Coarse fragments in the control section range from 15 to 35 percent. The mean annual soil temperature at 20 inches ranges from 45 to 47 degrees F. The mean summer soil temperature ranges from 60 to 63 degrees F. In more than 7 out of 10 years the soils are dry in the moisture control section for 60 to 80 consecutive days during the summer months, but are moist in all parts of the moisture control section about 55 percent of the time that soil temperature at 20 inches is above 41 degrees F., and are moist for 65 to 75 consecutive days during the 120 days after the winter solstice.
The Al horizon is very dark grayish brown, brown, dark brown or dark gray. It has value of 3 through 5 dry and 2 or 3 moist, and chroma of 1 through 3. This horizon is neutral to mildly alkaline and is slightly to strongly calcareous.
The Cca horizon has hue of 10YR or 2.5Y, value of 5 through 8 dry and 3 through 7 moist, and chroma of 2 or 3. It is cobbly heavy silt loam, cobbly silty clay loam or very shaly silt loam with 25 to 35 percent clay. This horizon is mildly to strongly alkaline.
COMPETING SERIES: These are the Calita, Collinston, Emmons, Kitchell, Mill Hollow, Mower, Sanpitch, Toehead and Watkins Ridge series. Calita, Collinston, and Mill Hollow soils have mean annual soil temperature of more than 47 degrees F. Calita, Collinston, Emmons, Sanpitch, Toehead and Watkins Ridge soils have less than 40 percent carbonates in their control section. Kitchell soils have mean summer soil temperature of less than 59 degrees F. and more than 35 percent coarse fragments in the control section. Calita, Collinston, Mill Hollow, Mower, Sanpitch, and Watkins Ridge soils have mollic epipedons less than 20 inches thick. Calita, Mill Hollow and Sanpitch soils have an aridic moisture regime.
SETTING: Sedwell soils are on moderately steep to steep mountain slopes at elevations of 6,800 to 7,800 feet. They formed in alluvium and colluvium from limestone and shale. The climate is moist subhumid and the average annual precipitation ranges from 14 to 20 inches. Mean annual temperature ranges from 43 to 45 degres F. Frost-free period is 90 to 110 days.
PRINCIPAL ASSOCIATED SOILS: These are the Ant Flat, Atepic, Clegg, Deer Creek and Lizzant soils. Ant Flat, Clegg and Deer Creek soils have argillic horizons. Atepic soils are less than 20 inches deep over shale and have ochric epipedons. Lizzant soils have more than 35 percent coarse fragments in their control section.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for range. Principal vegetation is oakbrush, snowberry, big sagebrush, maple, peavine, needle and thread grass, and scattered Rocky Mountain red cedar.
DISTRIBUTION AND EXTENT: Central Utah. The series is inextensive.
SERIES ESTSABLISHED: Sanpete Survey Area, Utah, 1971.
REMARKS: In the 1938 classification these soils were classified as Calcisols.
OSED scanned by NSSQA. Last revised by state 8/71.