LOCATION SHEEPSPRINGS ORTentative Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Aquandic Endoaquolls
TYPICAL PEDON: Sheepsrings ashy silt loam at an elevation of 1,360 meters, rangeland. (Colors are for moist soil unless otherwise noted.)
A1--0 to 17 cm; very dark grayish brown (10YR 3/2) ashy silt loam, brown (10YR 5/3) dry; weak medium and fine granular structure; slightly hard, friable, moderately sticky, moderately plastic; many medium, fine, and very fine roots; many very fine interstitial pores; 2 percent distinct brown (7.5YR 5/4) masses of oxidized iron; 2 percent fine gravel; strongly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (10 to 45 cm thick)
A2--17 to 24 cm; very dark grayish brown (10YR 3/2) ashy sandy clay loam, brown (10YR 5/3) dry; weak medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many medium, fine, and very fine roots; many very fine interstitial pores; 4 percent distinct brown (7.5YR 5/4) masses of oxidized iron and 4 percent manganese masses; 2 percent fine gravel; slightly alkaline (pH 7.6); clear smooth boundary. (7 to 30 cm thick)
A3--24 to 29 cm; very dark grayish brown (10YR 3/2) ashy coarse sandy loam, brown (10YR 5/3) dry; single grain; loose, nonsticky, nonplastic; many medium, fine, and very fine roots; many very fine interstitial pores; 2 percent fine gravel; slightly alkaline (pH 7.6); clear smooth boundary. (Combined thickness of A3 and A4 horizons of 5 to 20 cm)
A4--29 to 42 cm; very dark grayish brown (10YR 3/2) ashy loam, brown (10YR 5/3) dry; weak medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many medium, fine, and very fine roots; many very fine tubular and interstitial pores; 1 percent prominent strong brown (7.5YR 5/6) masses of oxidized iron in matrix; 2 percent fine gravel; slightly alkaline (pH 7.6); clear smooth boundary.
Bg--42 to 72 cm; black (5Y 2.5/2) ashy loam, olive (5Y 5/3) dry; weak medium subangular blocky structure; slightly hard, friable, moderately sticky, moderately plastic; many medium, fine, and very fine roots; common fine interstitial and very fine tubular pores; 3 percent prominent strong brown (7.5YR 5/6) masses of oxidized iron in matrix; 2 percent fine gravel and 2 percent gravel; slightly alkaline (pH 7.6); clear wavy boundary. (6 to 30 cm thick)
C1--72 to 90 cm; very dark grayish brown (10YR 3/2) very gravelly ashy coarse sand, brown (10YR 5/3) dry; single grain; loose, nonsticky, nonplastic; 40 percent fine gravel and 5 percent gravel; slightly alkaline (pH 7.6). (15 to 25 cm thick)
C2--90 to 110 cm; very dark grayish brown (2.5Y 3/2) ashy silt loam, very dark grayish brown (2.5Y 3/2) dry; massive; slightly hard, friable, nonsticky, nonplastic; 1 percent prominent strong brown (7.5YR 5/6) masses of oxidized iron; 5 percent fine gravel and 5 percent gravel; slightly alkaline (pH 7.6). (13 to 50 cm thick)
C3--110 to 130 cm; very dark grayish brown (2.5Y 3/2) very gravelly ashy sandy loam, very dark grayish brown (2.5Y 3/2) dry; massive, nonsticky, nonplastic; 30 percent fine gravel and 15 percent gravel; slightly alkaline (pH 7.6). (Combined thickness of C3 and C4 horizons is 15 to 40 cm)
C4--130 to 145 cm; olive brown (2.5Y 4/3) ashy silt loam, olive brown (2.5Y 4/3) silt loam, dry; massive; slightly hard, friable, nonsticky, nonplastic; 2 percent faint dark yellowish brown (10YR 4/4) masses of oxidized iron and 3 percent 10YR 6/1 iron depletions; 5 percent fine gravel and 5 percent gravel and 2 percent cobbles; slightly alkaline (pH 7.6).
TYPE LOCATION: Malheur County, Oregon; Approximately 3.5 miles south of Jordan Valley, Oregon; UTM 494389 easting, 4751929 northing, zone 11, NAD83 on the USGS Jordan Valley 7.5 minute quadrangle; latitude 42 degrees 55 minutes 12.00 seconds N and longitude 117 degrees 4 minutes 8.00 seconds W; NAD83.
RANGE IN CHARACTERISTICS:
Soil moisture - The soil moisture control section is moist in late summer and fall and saturated in winter, spring, and early summer; aquic moisture regime.
Soil temperature - 7 to 8 degrees C.
Mollic epipedon thickness - 30 to 55 cm.
Other Features - Redoximorphic features are present at the soil surface.
Control section - Percent clay - Stratified; fine-loamy horizons range from 18 to 27 percent, contrasting sandy horizons range from 1 to 6 percent; non-contrasting subhorizons with 10 to 18 percent clay are present in most pedons.
Rock fragments - 0 to 5 percent in the upper part and averages 15 to 35 percent in the lower part.
A1 horizon -
Hue: 2.5Y or 10YR.
Value: 4 or 5 dry.
Chroma: 2 or 3 dry, 1 to 3 moist.
Effervescence: None through strongly effervescent.
Reaction: Slightly alkaline through moderately alkaline.
Redoximorphic features: 2 to 10% distinct iron concentrations (7.5YR 5/4)
Volcanic glass: Volcanic glass is estimated to range from 30 to 50 percent of the 0.02 to 2 mm fraction.
A2 horizon -
Value: 4 or 5 dry.
Chroma: 1 to 3 moist.
Texture: Sandy clay loam, clay loam, silt loam.
Clay content: 18 to 35 percent.
Rock fragments: Averages 0 to 5 percent gravel.
Effervescence: None to slightly effervescent.
Reaction: Slightly alkaline through moderately alkaline.
Redoximorphic Features: 0 to 20% distinct iron and manganese concentrations
Volcanic glass: Volcanic glass is estimated to range from 30 to 50 percent of the 0.02 to 2 mm fraction.
A3 and A4 horizons -
Chroma: 1 or 2 moist
Texture: Coarse sandy loam, loam, silt loam.
Clay content: 10 to 25 percent.
Rock fragments: Averages 0 to 5 percent gravel.
Redoximorphic features: 0 to 5% distinct oxidized iron concentrations.
Volcanic glass: Volcanic glass is estimated to range from 10 to 25 percent of the 0.02 to 2 mm fraction.
Bg horizon -
Hue 2.5Y or 5Y.
Value: 2.5 or 3 moist.
Chroma: 1 or 2 moist.
Texture: Loam, sandy clay loam.
Clay content: 18 to 27 percent.
Rock fragments: Averages 0 to 5 percent gravel.
Redoximorphic features: 2 to 3% distinct iron concentrations
Volcanic glass: Volcanic glass is estimated to range from 10 to 25 percent of the 0.02 to 2 mm fraction.
C1 horizon -
Hue: 2.5Y or 10YR.
Value: 2 to 5 moist.
Chroma: 1 to 3 moist.
Texture: Coarse sand, sand.
Percent clay: 1 to 6.
Rock fragments: Averages 15 to 35 percent gravel; individual strata range from 10 to 45 percent.
Redoximorphic features: 0 to 30% distinct iron concentrations, 0 to 2% manganese concentrations.
Volcanic glass: Volcanic glass is estimated to range from 10 to 25 percent of the 0.02 to 2 mm fraction.
C2 and C3 horizons -
Hue: 5Y, 2.5Y or 10YR.
Value: 2 to 5 moist.
Chroma: 1 to 4 moist.
Texture: Stratified sandy loam to clay loam.
Clay content: Averages 12 to 30 percent.
Rock fragments: Averages 0 to 20 percent gravel.
Redoximorphic features: 0 to 30% iron and manganese concentrations, 0 to 4% iron depletions.
Volcanic glass: Volcanic glass is estimated to range from 10 to 25 percent of the 0.02 to 2 mm fraction.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Sheepsprings soils are on floodplains. These soils formed in mixed loess, volcanic ash, and alluvium. Slopes range from 0 to 4 percent. Elevations are 1,340 to 1,370 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 300 to 400 mm; mean annual temperature is 5 to 7 degrees C, and the frost free season is 50 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Zola soils. Zola soils are fine-loamy and have Bk horizons.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained, wet at or near the surface in spring, fall, and winter, low runoff, moderately high saturated hydraulic conductivity,
USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly baltic rush and tufted hairgrass.
DISTRIBUTION AND EXTENT: Southeast Oregon; the soil is of small extent. MLRA 25.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Malheur County, Oregon, Southern Part, 2008.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to about 42 cm.
Particle control section - The zone from 25 to 100 cm (A3, A4, Bg, C1, and C2 horizons).