LOCATION MANASSA UT+IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, active, calcareous, mesic Xeric Torriorthents
TYPICAL PEDON: Manassa silt loam--rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 2 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; weak fine granular structure; soft, friable, slightly sticky and slightly plastic; many very fine roots; few very fine pores; violently effervescent; carbonates are disseminated; moderately alkaline (pH 8.2); abrupt smooth boundary. (1 to 3 inches thick)
A2--2 to 6 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; weak thin platy structure parting to weak fine granular; soft, firm, sticky and plastic; common very fine, few fine and medium roots; few very fine and fine pores; violently effervescent; carbonates are disseminated; strongly alkaline (pH 8.6); clear smooth boundary. (4 to 6 inches thick)
C1--6 to 12 inches; very pale brown (10YR 7/3) silt loam, brown (10YR 5/3) moist; weak fine granular structure; slightly hard, firm, sticky and plastic; common fine and few medium roots; few fine pores; violently effervescent; carbonates are disseminated; strongly alkaline (pH 8.8); clear smooth boundary. (5 to 6 inches thick)
C2--12 to 25 inches; pink (7.5YR 7/3) silty clay loam, brown (7.5YR 5/3) moist; moderate medium subangular blocky structure; hard, very firm, sticky and plastic; few very fine and fine roots; few very fine and fine pores; violently effervescent; carbonates are disseminated; very strongly alkaline (pH 9.2); clear smooth boundary. (9 to 14 inches thick)
C3--25 to 33 inches; pink (7.5YR 7/3) silty clay loam, brown (7.5YR 5/3) moist; weak medium subangular blocky structure; very hard, firm, sticky and plastic; few very fine roots; common very fine, few fine and medium pores; violently effervescent; carbonates are disseminated; very strongly alkaline (pH 9.2); clear wavy boundary. (6 to 9 inches thick)
C4--33 to 54 inches; light brown (7.5YR 6/3) loam, brown (7.5YR 5/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few very fine pores; violently effervescent; carbonates are disseminated; very strongly alkaline (pH 9.2); gradual smooth boundary. (15 to 24 inches thick)
C5--54 to 60 inches; light brown (7.5YR 6/3) loam, brown (7.5YR 5/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine pores; violently effervescent; carbonates are disseminated; very strongly alkaline (pH 9.2).
TYPE LOCATION: Sanpete County, Utah; 4 miles north of Fayette, about 1,900 feet west, 2,300 feet south of the northeast corner of sec. 35, T. 17 S., R. 1 W.
RANGE IN CHARACTERISTICS:
The mean annual soil temperature ranges from 47 to 51 degrees F. The soils are dry in the moisture control section for 51 to 55 percent of the time the soil temperature at a depth of 20 inches is above 41 degrees F. The soil moisture regime is Aridic bordering on Xeric.
These soils are saline-alkali and range from moderately alkaline to very strongly alkaline. The sodium adsorption ratio is 13 or higher throughout the profile.
The A horizon has hue of 10YR or 7.5YR, value of 6 or 7 dry, 4 or 5 moist, and chroma of 2 through 4. Calcium carbonate equivalent is 3 to 20 percent. Clay content is 18 to 27 percent.
The C horizon has hue of 10YR or 7.5YR, value of 6 to 8 dry, 4 to 7 moist, and chroma of 2 to 4. It ranges from silty clay to fine sandy loam, but the particle-size control section averages 18 to 35 percent clay and less than 15 percent sand coarser than very fine sand. Below a depth of 40 inches textures range from fine sandy loam to silty clay. Calcium carbonate equivalent is 15 to 40 percent.
COMPETING SERIES: There are currently no other series in this family.
GEOGRAPHIC SETTING: Manassa soils are on fan remnants, flood plains, lake plains, and lake terraces. They formed in alluvium and lacustrine sediments from shale, sandstone and limestone. Slopes are 0 to 6 percent. Elevations range from 4,250 to 6,000 feet. The climate is semiarid. The mean annual precipitation ranges from 8 to 12 inches. The mean annual temperature ranges from 45 to 52 degrees F. and the mean summer temperature ranges from 65 to 69 degrees F. The frost-free period is 100 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Mellor and Oasis soils. Mellor soils have natric horizons. Oasis soils have less than 18 percent clay in the particle-size control section.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; slow permeability.
USE AND VEGETATION: These soils are used for native range pasture. Potential vegetation is greasewood, shadscale, squirreltail, and western wheatgrass.
DISTRIBUTION AND EXTENT: Central Utah. The series is not extensive. MLRAs 11, 28A, and 47.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: Richfield Area, 1947.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from the surface to 6 inches (A1 and A2 horizons).
Particle-size control section - the zone from 10 to 40 inches (part of the C1 horizon, the C2 and C3 horizons, and part of the C4 horizon).
The active cation exchange activity class was added to the taxonomic classification in December 2002 based on soil property data.
In 1983, the type location was changed from the original location in Upper Round Valley, Utah to this site north of Fayette, Utah.