LOCATION ESPLIN                  UT

Established Series
Rev. KMD/RSJ/MJD/WWJ
08/2019

ESPLIN SERIES

The Esplin series consists of shallow over indurated carbonate hardpan, well drained soils that formed in igneous rocks. The Esplin soils are on lava flows and alluvial fans. Slopes range from 0 to 3 percent. The mean annual air temperature is about 54 degrees F., and the mean annual precipitation is about 12 inches.
TAXONOMIC CLASS: Loamy, mixed, superactive, mesic, shallow Ustalfic Petrocalcids
TYPICAL PEDON: Esplin loam, rangeland. (Colors are for air dry soil unless otherwise noted.)
A--0 to 8 cm (0 to 3 inches); reddish brown (5YR 4/4) loam, yellowish red (5YR 4/6) moist; moderate very fine granular structure; soft, friable, slightly sticky and slightly plastic; common fine and few medium roots; few fine vesicular pores; about 10 percent of the surface covered with basalt gravel and hardpan fragments; noncalcareous; moderately alkaline (pH 8.2); clear smooth boundary. (1 to 5 inches thick)
Bt--8 to 18 cm (3 to 7 inches); dark red (2.5YR 3/6) clay loam, dark red (2.5YR 3/6) moist; weak coarse prismatic structure that parts to moderate medium subangular blocky structure; very hard, firm, sticky and plastic; common fine and medium roots; common fine and few medium interstitial pores; common moderately thick clay films in pores and on faces of some peds; noncalcareous; moderately alkaline (pH 8.0); clear smooth boundary. (4 to 8 inches thick)
Btk--18 to 25 cm (7 to 10 inches); yellowish red (5YR 4/6) silty clay loam, yellowish red (5YR 4/6) moist; moderate medium subangular blocky structure; hard, friable, sticky and plastic; common fine and medium roots; common fine and few medium interstitial pores; strongly effervescent, carbonates are present as accretions and veins; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 6 inches thick)
Bk--25 to 46 cm (10 to 18 inches); light reddish brown (5YR 6/4) silt loam, yellowish red (5YR 5/6) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and few medium roots; common fine and few medium interstitial pores; strongly effervescent, carbonates are present as accretions and veins; strongly alkaline (pH 8.8); abrupt smooth boundary. (0 to 8 inches thick)
Bkm--46 cm (18 inches); indurated carbonate hardpan.
TYPE LOCATION: Washington County, Utah; 3/4 mile southwest of Frog Hollow Dam; 400 feet south and 300 feet west of the northeast corner of section 26, T.42S., R.13W; The Divide Quadrangle; lat. 37 degrees 6 minutes 41 seconds N. and long. 113 degrees 16 minutes 29 seconds W.
RANGE IN CHARACTERISTICS:
Depth to the petrocalcic: 33 to 51 cm (13 to 20 inches)
Gravel cover on soil surface: 3 to 80 percent
Mean annual soil temperature: 54 to 58 degrees F.
Soil moisture: The soils are usually dry during the period the soil temperature is above 41 degrees F. They are moist in some parts of the moisture control section for 30 to 40 days during the summer months and are dry for 70 to 85 days during the 120 days following the winter solstice. Ustic aridic moisture regime.
Reaction: slightly alkaline to moderately alkaline.
A horizon
Hue: 5YR or 7.5YR
Value: 4 through 6 dry, 3 or 4 moist (Combined color value of 4 or 5 dry and 3 moist extend to depth of less than 18 cm (7 inches))
Chroma: 2 through 6.
Bt and Btk horizons
Hue: 2.5YR or 5YR
Value: 3 moist, 3 or 4 dry
Chroma: 6
Texture: clay loam, silty clay loam or sandy clay loam
Structure: weak to moderate, medium to coarse prismatic that parts to weak or strong, very fine to coarse subangular blocky or angular blocky
Bk horizon
Hue: 5YR
Value: 5 moist, 6 dry
Chroma: 4 to 6
Texture: silt loam
COMPETING SERIES: The Horsemountain (UT) series. Horsemountain soils formed in alluvium derived from sedimentary rock on fans remnants.
GEOGRAPHIC SETTING: Esplin soils are on old lava flows or old alluvial fans at elevations of 3,800 to 4,600 feet. They formed from igneous parent materials. Slopes range from 0 to 3 percent. The mean annual temperature is 52 to 56 degrees F., and the mean summer temperature is 72 to 77 degrees F. The average annual precipitation is 10 to 13 inches. The frost free season is 160 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pastura soils. Pastura soils lack argillic horizons.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate permeability.
USE AND VEGETATION: Used as rangeland. Vegetation is blackbrush, Mormon tea, sagebrush, rabbitbrush, cliffrose, cholla, galleta and cheatgrass.
DISTRIBUTION AND EXTENT: Southwestern Utah. MLRAs 29 & 35. The series is inextensive.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: Washington County, Utah, 1972.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from a depth of 0 to 3 inches (A horizon)
Argillic horizon - from a depth of 3 to 10 inches (Bt and Btk horizon)
Calcic horizon - from a depth of 7 to 18 inches (Btk and Bk horizon)
Petrocalcic horizon - at a depth of 18 inches (Bkm horizon)
Classified according to Soil Taxonomy Second Edition, 1999.
Classification was changed from Petrocalcic Ustollic Paleargids to Ustalfic Petrocalcids in 12/94.
The classification change referred to by the 12/94 remark did not become official, so this change was made at the request of Region 4. tdc 7/2019
The classification change affected the competing series section, which was changed. tdc 7/2019
Added metric units to horizon descriptions. tdc 7/2019
Classified according to Soil Taxonomy Twelfth Edition, 2014. It was assumed that calcic horizon criteria was met in the Btk and Bk horizons. No KSSL data exists for the Esplin series. tdc 7/2019

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National Cooperative Soil Survey
U.S.A.