LOCATION HARDING UTEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, mesic Xeric Natrargids
TYPICAL PEDON: Harding silt loam, rangeland. (Colors are for air dry soils unless otherwise noted.)
A--0 to 4 inches; pale brown (10YR 6/3) silt loam, brown (10YR 4/3) moist; moderate thin platy structure; soft, friable, sticky and slightly plastic; common very fine roots; few very fine pores; moderately calcareous, disseminated carbonates; strongly alkaline (pH 8.8); abrupt smooth boundary. (2 to 4 inches thick.)
AB--4 to 10 inches; pale brown (10YR 6/3) silty clay, brown (10YR 5/3) moist; moderate medium subangular blocky structure; hard, firm, very sticky and very plastic; few very fine and fine roots; few very fine and fine pores; strongly calcareous disseminated carbonates; strongly alkaline (pH 8.6); clear smooth boundary. (0 to 6 inches thick.)
Btkn1--10 to 23 inches; very pale brown (10YR 7/3) silty clay; brown (10YR 5/3) moist; strong coarse prismatic structure that parts to strong fine angular blocky; very hard, extremely firm, very sticky and very plastic; few fine roots between peds; many moderately thick clay films on faces of peds; strongly calcareous, carbonates in soft rounded masses in peds mainly at the top of prisms; very strongly alkaline (pH 9.2); clear smooth boundary.
Btkn2--23 to 30 inches; pale brown (10YR 6/3) silty clay, brown (10YR 5/3) moist; moderate coarse prismatic structure that parts to strong fine angular blocky; hard, extremely firm, very sticky and very plastic; few very fine roots; common thick clay films on faces of peds; strongly calcareous, carbonates disseminated and in veins and rounded masses; very strongly alkaline (pH 9.6); gradual wavy boundary. (Combined thickness of the Btkn horizons is 12 to 28 inches thick.)
Btky--30 to 54 inches; pale brown (10YR 6/3) silty clay, brown (10YR 5/3) moist; strong coarse angular blocky rock structure; very hard, extremely firm, very sticky and very plastic; common fine gypsum veins; strongly calcareous, disseminated carbonates; moderately alkaline (pH 8.4); clear smooth boundary. (0 to 26 inches thick.)
C--54 to 60 inches; light gray (10YR 7/2) silt loam, grayish brown (10YR 5/2) moist; platy rock structure; slightly hard, friable, slightly sticky and slightly plastic; moderately calcareous, disseminated carbonates; strongly alkaline (pH 9.0).
TYPE LOCATION: Juab County, Utah; about 2.5 miles west and 1 mile south of Mills; 1,300 feet west and 800 feet north of the southeast corner of sec. 33, T.15 S., R.2 W.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in winter and spring and for brief periods in summer due to convection storms. Aridic bordering xeric soil moisture regime.
Mean annual soil temperature: More than 47 degrees F.
Control section:
Texture: Silty clay loam, silty clay, or clay.
Clay content: 35 to 55 percent.
A horizon:
Hue: 10YR or 7.5YR.
Value: 6 or 7 dry, and 4 or 5 moist.
Chroma: 2 or 3, dry or moist.
Structure: Weak to moderate, thin to thick platy.
AB horizon:
Hue: 10YR or 7.5YR.
Value: 6 to 8 dry.
Btn horizon:
Hue: 10YR or 7.5YR.
Value: 6 or 7 dry, and 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Silty clay loam, silty clay, or clay.
Clay content: 35 to 55 percent.
Calcium carbonate equivalent: 15 to 40 percent.
Reaction: Strongly alkaline to very strongly alkaline.
Structure: Moderate to strong prismatic or columnar and breaks to moderate or strong blocky.
Other features: Organic staining is evident on the ped faces in most pedons. Some pedons have Btky horizons with 1 to 3 percent secondary gypsum masses and filaments.
Bky horizon: (when present)
Value: 6 to 8 dry, and 5 to 7 moist.
Chroma: 2 or 3, dry or moist.
Gypsum: 1 to 10 percent.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Harding soils are on nearly level to gently sloping lake terraces, lake plains, and flood plains at elevations of 4,200 to 5,600 feet. Slopes are 0 to 5 percent. These soils formed in alluvium and lacustrine deposits from sandstone, limestone, and shale. Mean annual temperature ranges from 45 to 52 degrees F., mean summer temperature is about 67 F. The freeze-free period is 100 to 140 days. The average annual precipitation is 8 to 12 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Manassa, Taylorsville, and Woodrow series. Manassa, Taylorsville, and Woodrow soils lack Bt horizons and Taylorsville and Woodrow soils are not strongly sodium affected.
DRAINAGE AND PERMEABILITY: Well and moderately well drained. Runoff is medium and high. Permeability is slow and very slow.
USE AND VEGETATION: Principally winter rangeland. Present vegetation is dominantly greasewood, bottlebrush squirreltail and shadscale.
DISTRIBUTION AND EXTENT: Central and western Utah. The soil is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES ESTABLISHED: East Millard Area, Utah, 1944.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: The zone from 0 to 4 inches. (A horizons)
Natric horizon: The zone from 10 to 30 inches. (Btn1 and Btn2 horizons)
The type location was changed to the Fairfield-Nephi Soil Survey in April 2003.