LOCATION SILTCLIFFE UTTentative Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Haplocalcids
TYPICAL PEDON: Siltcliffe very fine sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with about 15 percent gravel.
A--0 to 4 inches; light brownish gray (10YR 6/2) very fine sandy loam, dark grayish brown (10YR 4/2), moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine, few medium roots; many fine and very fine vesicular and few medium tubular pores; very slightly effervescent; moderately alkaline (pH 8.0); abrupt smooth boundary. (2 to 5 inches thick)
Bw--4 to 10 inches; light yellowish brown (10YR 6/4) very fine sandy loam, dark yellowish brown (10YR 4/4), moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky, slightly plastic; many fine, very fine and few medium roots; common fine and few medium tubular pores; few very thin (< 1 mm) carbonate coats on rock fragments; 2 percent fine prominent irregular carbonate masses in matrix and 1 percent medium prominent irregular carbonate masses in matrix; 5 percent gravel; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (0 to 8 inches thick)
Bk1--10 to 31 inches; light yellowish brown (10YR 6/4)paragravelly sandy clay loam, dark yellowish brown (10YR 4/4), moist; moderate medium subangular blocky structure; moderately hard, friable, slightly sticky, slightly plastic; common fine, few medium and very fine roots; few fine and medium tubular pores; few very thin (< 1 mm) carbonate coats on rock fragments; 5 percent fine prominent irregular carbonate nodules in matrix; 10 percent gravel; violently effervescent; strongly alkaline (pH 8.6); clear wavy boundary.
Bk2--31 to 52 inches; light yellowish brown (10YR 6/4) gravelly sandy clay loam, dark yellowish brown (10YR 4/4), moist; moderate medium subangular blocky structure; moderately hard, very friable, slightly sticky, slightly plastic; few fine and medium roots; few fine and medium tubular pores; few very thin (< 1 mm) carbonate coats on rock fragments; 15 percent fine prominent irregular carbonate nodules in matrix; 15 percent gravel; violently effervescent; strongly alkaline (pH 8.6); abrupt wavy boundary.
2C--52 to 60 inches; light yellowish brown (10YR 6/4) extremely gravelly coarse sandy loam, dark yellowish brown (10YR 4/4), moist; massive parting to single grain; loose, nonsticky, nonplastic; 75 percent gravel; strongly effervescent; strongly alkaline (pH 8.6).
TYPE LOCATION: Beaver County, Utah; Frisco USGS quadrangle; latitude 38 degrees 25 minutes 57.30 seconds N. and longitude 113 degrees 21 minutes 56.10 seconds W., Datum: NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry, moist in some part for 10 to 20 days (cumulative) in summer due to convection storms and during winter and spring.
Soil temperature: 53 to 59 degrees F.
Depth to calcic horizon: 4 to 12 inches.
Thickness of the calcic horizon: 30 to 50 inches.
Particle-size control section (weighted average):
Clay content: 18 to 25 percent.
Rock fragments: 0 to 15 percent, mainly gravel.
A horizon - Value: 4 or 5 moist
Chroma: 2 to 4, dry or moist
Calcium carbonate equivalent: 1 to 5 percent of the less than 2 mm fraction
Reaction: Moderately alkaline or strongly alkaline.
Bw horizon (when present) - Texture: Very fine sandy loam or sandy clay loam.
Clay content: 15 to 25 percent.
Structure: weak or moderate, medium subangular blocky.
Calcium carbonate equivalent: 5 to 15 percent of the less than 2 mm fraction.
Rock fragments: 0 to 5 percent gravel
Bk horizons - Value: 5 to 8 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist
Texture: Sandy clay loam or silt loam, thin subhorizons of silty clay loam or clay loam are in some pedons.
Sand content: Sand ranges from 25 to 60 percent, 15 to 25 percent is fine sand or coarser.
Clay content: 20 to 27 percent, some pedons have subhorizons with up to 35 percent.
Rock fragments: 0 to 25 percent gravel and 5 to 15 percent paragravel consisting mainly of carbonate nodules.
Durinodes: 0 to 5 percent moderately cemented durinodes.
Structure: Strong or moderate, medium subangular blocky.
Calcium carbonate equivalent: 15 to 40 percent of the less than 2 mm fraction.
Identifiable secondary carbonate: Carbonate as nodules, coatings and masses ranges from 5 to 15 percent by volume.
Reaction: Strongly alkaline or very strongly alkaline.
2C horizon - Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 to 4, dry or moist.
Texture: Loamy coarse sand, loamy sand or coarse sandy loam.
Clay content: 5 to 18 percent.
Rock fragments: 35 to 75 percent, mainly gravel.
Structure: Massive or single grain.
Calcium carbonate equivalent: 15 to 30 percent of the less than 2 mm fraction.
Reaction: Strongly alkaline.
COMPETING SERIES: These are the Avalon(CO), Kilroy(UT), Pariette(UT), and Redhouse(UT) series.
The Avalon soils are not intermittently moist for 10 to 20 days cumulative from July to September due to convection storms. Kilroy soils have 15 to 35 percent sandstone or quartzite rock fragments in the particle-size control section and are not intermittently moist for 10 to 20 days cumulative from July to September due to convection storms. Pariette soils have a paralithic contact at depths of 20 to 40 inches and are not intermittently moist for 10 to 20 days cumulative from July to September due to convection storms. Redhouse soils have hues of 5YR or redder and are not intermittently moist for 10 to 20 days cumulative from July to September due to convection storms redder and have 15 to 35 percent rock fragments in the particle-size control section that have sandstone or shale lithology.
GEOGRAPHIC SETTING: Siltcliffe soils are on alluvial flats and beach plains. These soils formed in alluvium and lacustrine deposits derived from mixed sedimentary and igneous rocks. Slopes range from 0 to 3 percent. Elevations range from 4,550 to 5,200 feet.
The mean annual precipitation is 6 to 8 inches, the mean annual air temperature is 50 to 55 degrees F and the frost-free period is 100 to
155 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Saltydog, Thermosprings, Hiko Springs and Dera soils. Saltydog series has less than 18 percent clay in the control section. Thermosprings soils have a natric horizon. Hiko Springs series has less than 18 percent clay in the control section and is gravelly. Dera soils are skeletal and occur on relict longshore bars.
DRAINAGE AND PERMEABILITY: Well drained; runoff is low; permeability is
moderate.
USE AND VEGETATION: Livestock grazing and wildlife habitat. The potential native
vegetation includes Indian ricegrass and winterfat. This pedon is correlated to Ecological Site 028AY140UT, Desert Silt Flat (Winterfat).
DISTRIBUTION AND EXTENT: Southwest Utah. These soils are not extensive. MLRA 28A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona.
SERIES PROPOSED: Beaver County, Utah, Western Part, 2007.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from 0 to 4 inches (A horizon).
Cambic horizon - The zone from 4 to 10 inches (Bw horizon).
Calcic horizon - The zone from 10 to 52 inches (Bk1 and Bk2 horizons).
Particle size control section - The zone from 10 to 40 inches (the
Bk1 and the upper part of the Bk2 horizon).