LOCATION SALTWELLS               WY

Tentative Series
DPG/DEW
03/2025

SALTWELLS SERIES

Depth Class: Very deep
Drainage class: Well drained
Saturated hydraulic conductivity class: Moderately high
Parent material: Alluvium weathered from interbedded sedimentary rocks
Geomorphic location: Alluvial flats
Slope range: 0 to 2 percent
Mean annual temperature: 4.5 degrees C (40 degrees F)
Mean annual precipitation: 205 millimeters (8 inches)

TAXONOMIC CLASS:
Fine-silty, mixed, superactive, frigid Ustic Haplargids

TYPICAL PEDON: Saltwells silt loam in rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 7 centimeters; light yellowish brown (2.5Y 6/3) silt loam, olive brown (2.5Y 4/3) moist; weak medium platy structure; soft, very friable, moderately sticky, moderately plastic; many very fine and fine roots, common medium and coarse roots throughout; many very fine and fine tubular pores; slightly effervescent; moderately alkaline (pH 8.4); clear smooth boundary.

Btn--7 to 20 centimeters; yellowish brown (10YR 5/4) silty clay loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many very fine and fine roots and common medium roots throughout; many very fine and fine tubular pores; 2 percent faint clay films on all faces of peds; slightly effervescent; strongly alkaline (pH 9.0); gradual smooth boundary.

Btz1--20 to 35 centimeters; yellowish brown (10YR 5/4) silty clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; common very fine, fine, and medium roots throughout; common very fine and fine tubular pores; 5 percent faint clay films on faces of peds and on surfaces along root channels; 2 percent fine masses of oxidized iron in matrix 15 percent salt crystals in matrix; slightly effervescent; moderately alkaline (pH 8.2); gradual smooth boundary.

Btz2--35 to 93 centimeters; yellowish brown (10YR 5/4) silty clay loam, dark yellowish brown (10YR 4/4) moist; moderate coarse subangular blocky structure; slightly hard, friable, very sticky, very plastic; common very fine and fine roots throughout; common very fine and fine tubular pores; 5 percent clay films on faces of peds and on surfaces along root channels; 20 percent salt crystals in matrix; slightly effervescent; moderately alkaline (pH 8.1); gradual smooth boundary.

Btz3--93 to 120 centimeters; pale brown (10YR 6/3) silty clay loam, dark yellowish brown (10YR 4/4) moist; moderate coarse subangular blocky structure; slightly hard, friable, very sticky, very plastic; common very fine and fine roots throughout; common very fine and fine tubular pores; 2 percent clay films on faces of peds and on surfaces along root channels; 10 percent salt crystals in matrix; slightly effervescent; moderately alkaline (pH 8.3); gradual smooth boundary.

BCz--120 to 150 centimeters; light yellowish brown (10YR 6/4) silty clay loam, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure; moderately hard, friable, very sticky, very plastic; 5 percent salt crystals in matrix; slightly effervescent; strongly alkaline (pH 8.5); gradual smooth boundary.

Cz--150 to 200 centimeters; pale brown (10YR 6/3) silty clay, brown (10YR 4/3) moist; massive; moderately hard, firm, very sticky, very plastic; 2 percent salt crystals in matrix; slightly effervescent; strongly alkaline (pH 8.7).

TYPE LOCATION:
Sweetwater County, WY
USGS Quadrangle: Point of Rock SW
Latitude: 41.574236
Longitude: -108.955648
Datum: WGS84
Coordinates source: Hand-held GPS

RANGE IN CHARACTERISTICS:
Depth to argillic horizon--5 to 7 centimeters
Particle-size control section (weighted averages)
Clay content--28 to 42 percent
Sand content--5 to 15 percent
Total rock fragments--0 to 15 percent

A
Hue--2.5Y
Value--6 or 7 dry; 4 moist
Chroma--2 or 3 dry; 3 moist
Texture (less than 2 mm fraction)--Loam or silt loam
Clay content--23 to 26 percent
Reaction--pH 7.9 to 8.5
Thickness--5 to 7 centimeters

Bt/Btn horizon(s) (when present)
Hue--10YR or 2.5Y
Value--5 or 6 dry; 4 moist
Chroma--3 or 4 dry; 3 moist
Texture (less than 2 mm fraction)--Silty clay loam
Clay content--28 to 32 percent
Calium carbonate equivalent--1 to 5 percent
Sodium absorption ratio--0 to 25
Reaction--pH 7.9 to 9.2
Thickness--0 to 60 centimeters

Btz/Btnz horizon(s)
Hue--10YR or 2.5Y
Value--5 or 6 dry; 3 or 4 moist
Chroma--3 or 4
Texture (less than 2 mm fraction)--Silty clay loam, silty clay
Clay content--31 to 42 percent
Calium carbonate equivalent--3 to 5 percent
Sodium absorption ratio--0 to 15
Electrical conductivity--1 to 8 dS/m
Reaction--pH 7.8 to 8.8
Thickness--100 to 143 centimeters

C/Cz horizon(s)
Hue--10YR or 2.5Y
Value--5 or 6 dry; 4 or 5 moist
Chroma--3 or 4
Texture (less than 2 mm fraction)--Silty clay, silty clay loam or clay loam
Clay content--32 to 43 percent
Sodium absorption ratio--6 to 15
Electrical conductivity--0 to 8 dS/m
Reactio--pH 8.4 to 9.0
Thickness--15 to 50 centimeters

COMPETING SERIES:
There are no competing series

GEOGRAPHIC SETTING:
Parent material-- Alluvium weathered from interbedded sedimentary rocks
Landform--Alluvial flats
Slope--0 to 2 percent
Mean annual temperature--2.5 to 7.0 degrees C (37 to 45 degrees F)
Mean annual precipitation--180 to 230 mm (7 to 9 inches)
Frost-free period--50 to 100 days
Elevation--1,940 to 1,990 meters (6,360 to 6,530 feet)
Climate--long, cold winters; cool, moist springs; short, warm summers

GEOGRAPHICALLY ASSOCIATED SOILS:
None listed.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage Class: Well drained
Saturated Hydraulic Conductivity: 0.5 to 5 m/sec

USE AND VEGETATION:
Saltwells soils are primarily used for rangeland. The potential native vegetation is Gardener's saltbush, bottlebrush squirreltail, greasewood, seepweed, tansy mustard, Indian ricegrass, basin wildrye, and western wheatgrass.

DISTRIBUTION AND EXTENT:
Saltwells soils are of small extent in southwestern Wyoming; MLRA 34A.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES PROPOSED:
Sweetwater County, WY 2021. The Saltwells series name is derived from a local area.

REMARKS:
Typical Pedon Taxonomic Features:
Ochric epipedon--0 to 7 centimeters (A horizon)
Argillic horizon--7 to 120 centimeters (Btn, Btz1, Btz2, and Btz3 horizons)
Particle-size control section--7 to 57 centimeters
Taxonomic Version: Keys to Soil Taxonomy, 13th edition (2022)

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National Cooperative Soil Survey
U.S.A.