LOCATION SILVERLAKE OREstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Calcic Argixerolls
TYPICAL PEDON: Silverlake silt loam, cropland. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 8 inches; very dark brown (10YR 2/2) silt loam, grayish brown (10YR 5/2) dry; moderate medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; slightly alkaline (pH 7.5); clear smooth boundary. (6 to 10 inches thick)
A--8 to 12 inches; very dark brown (10YR 2/2) silt loam, grayish brown (10YR 5/2) dry; moderate coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; slightly alkaline (pH 7.5); abrupt wavy boundary. (0 to 5 inches thick)
2Btk1--12 to 18 inches; dark brown (7.5YR 3/3) silty clay loam, brown (10YR 4/3) dry; moderate medium and coarse subangular blocky structure; very hard, firm, slightly sticky and moderately plastic; few very fine roots; few very fine tubular pores; many distinct clay films; lime segregated in common fine and medium soft masses and as coatings on the underside of rock; strongly effervescent; 10 percent gravel; slightly alkaline (pH 7.8); clear wavy boundary. (4 to 8 inches thick)
2Btk2--18 to 24 inches; dark brown (7.5YR 3/4) clay, dark yellowish brown (10YR 4/4) dry; moderate fine and medium prismatic structure; very hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine tubular pores; continuous prominent clay films; lime segregated in many 4 to 8 mm seams; strongly effervescent; slightly alkaline (pH 7.8); abrupt wavy boundary. (6 to 14 inches thick)
3Bk1--24 to 31 inches; dark yellowish brown (10YR 4/4) silty clay loam, very pale brown (10YR 7/4) dry; massive; slightly hard, very friable, moderately sticky and slightly plastic; few very fine roots; common very fine tubular pores; violently effervescent; moderately alkaline (pH 8.0); gradual wavy boundary. (5 to 19 inches thick)
3Bk2--31 to 42 inches; light yellowish brown (10YR 6/4) very gravelly silt loam, very pale brown (10YR 8/3) dry; massive; soft, very friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; rock fragments are completely coated with lime; violently effervescent; 30 percent gravel and 15 percent cobbles; moderately alkaline (pH 7.9); clear wavy boundary. (5 to 16 inches thick)
4Bkqm--42 to 57 inches; brown (10YR 5/3), strongly cemented duripan; very pale brown (10YR 7/3) dry; strongly effervescent; 50 percent lime coated gravel; moderately alkaline (pH 7.9). (5 to 20 inches thick)
4C--57 to 63 inches; dark grayish brown (2.5Y 4/2) very gravelly loamy sand, light brownish gray (2.5Y 6/2) dry; single grain; loose, nonsticky and nonplastic; 50 percent gravel; moderately alkaline (pH 7.9).
TYPE LOCATION: Wallowa County, Oregon; about 2 miles NE of Joseph; 1,300 feet east and 30 feet south of the NW corner of section 27, T. 2 S., R. 45 E.
RANGE IN CHARACTERISTICS: Silverlake soils are usually moist but are dry in all parts of the moisture control section for 60 to 90 consecutive days following the summer solstice. The mean annual soil temperature is 44 to 47 degrees F. The mollic epipedon is 10 to 20 inches thick and may include part of the argillic horizon. The depth to the 2Btk horizon ranges from 10 to 15 inches. The particle-size control section is 35 to 45 percent clay. The depth to the strongly cemented duripan is 40 to 60 inches.
The Ap and A horizons have value of 2 or 3 moist, 3 to 5 dry, and chroma of 2 or 3 moist and dry. Soil reaction is neutral or slightly alkaline.
The 2Btk horizons have hue of 5YR, 7.5YR, and 10YR. The upper part of the 2Btk horizon has value of 3 or 4 moist, 3 to 5 dry and chroma of 2 or 3 moist, 3 or 4 moist and dry. The lower part has value of 3 or 4 moist, 3 to 6 dry, and chroma of 3 or 4 moist and dry. The 2Btk horizons are clay or silty clay loam with 35 to 45 percent clay. It has 0 to 25 percent gravel and 0 to 15 percent cobbles. Segregated lime may appear as filaments or soft masses or in seams. Soil reaction is slightly or moderately alkaline. It has 5 to 10 percent CaCO3 equivalent.
The 3Bk horizons have hue of 10YR or 7.5YR, value of 4 to 7 moist, 5 to 8 dry and chroma of 2 to 4 moist and dry. The 3Bk horizon has 0 to 30 percent gravel and 0 to 15 percent cobbles. The 3Bk1 horizon is gravelly silt loam, gravelly loam, silty clay loam, or gravelly clay loam with 25 to 35 percent clay and less than 35 percent total rock fragments. The 3Bk2 horizon is very gravelly silt loam, gravelly silt loam, gravelly loam, gravelly clay loam, or silty clay loam. It has less than 40 percent total rock fragments. Soil reaction is slightly or moderately alkaline. It has 5 to 10 percent CaCO3 equivalent.
The 4Bkqm horizon has value of 5 to 7 moist, 7 or 8 dry, and chroma of 3 to 6 moist and dry. It is strongly cemented and has 35 to 60 percent gravel. Soil reaction is slightly to moderately alkaline.
The 4C horizon lacks carbonates and cementation. It is very gravelly or extremely gravelly loamy sand with 30 to 60 percent gravel and 0 to 15 percent cobbles. Soil reaction is slightly to moderately alkaline.
COMPETING SERIES: These are the Ant Flat, Durkee, Gemid (T) and Soen (T) series. Ant Flat and Soen soils lack a duripan (Bkqm hrizon) between depths of 40 and 60 inches. Gemid soils are not in the database and cannot be competed.
GEOGRAPHIC SETTING: The Silverlake soils are on outwash terraces. Slopes are 0 to 3 percent. Elevation is 3,800 to 4,400 feet. They formed in glaciofluvial deposits and are influenced by loess in the surface horizons. The climate is characterized by cold wet winters and hot dry summers. The mean annual precipitation is 13 to 17 inches. The mean annual temperature is 42 to 45 degrees F. The mean frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chesnimnus, Reavis, Redmount, and Zumwalt series. Chesnimnus, Reavis, Redmount, and Zumwalt soils are located on adjacent terraces but lack an abrupt increase in clay. Chesnimnus and Reavis soils are fine-loamy. Redmount soils are coarse-loamy. Zumwalt soils are 20 to 40 inches to a lithic contact.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability in the surface horizons and slow in the subsoil.
USE AND VEGETATION: These soils are used for small grains, alfalfa, and hay & pasture under irrigation. The native vegetation is Idaho fescue and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Northeastern Oregon; MLRA 9. This series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wallowa County Area, Oregon, l998. Source of name is Silver Lake ditch located north of Wallowa Lake, near Joseph, Oregon.
REMARKS: Diagnostic horizons and features in this pedon are:
Mollic epipedon - the zone from the surface of the soil to a depth of 18 inches (Ap, A, and 2Btk1 horizons).
Argillic horizon - the zone from 12 to 24 inches (2Btk1 and 2Btk2 horizons).
Calcic horizon - the zone from 12 to 24 inches.
Duripan (strongly cemented) - 42 to 57 inches (4Bkqm horizon)
Particle-size control section - 12 to 24 inches (2Btk1 and 2Btk2 horizons) averaging 40 percent clay and 5 percent gravel.
Classification revised 08/2001 from a Typic Palexerolls to a Calcic Argixerolls based on laboratory data.
ADDITIONAL DATA: Partial laboratory data available for this soil. Reference sample #S90OR-063-000, Wallowa County, OR, NSSL, 4/90.