LOCATION SINGSAAS           SD+MN
Established Series
Rev. WTS-RCG-BOK-AGG
09/2005

SINGSAAS SERIES


The Singsaas series consists of very deep, well drained soils formed in a thin mantle of silty material over glacial till or in glacial till on uplands. The saturated hydraulic conductivity is moderate in the mantle and moderately slow in the till. Slopes range from 0 to 9 percent. Mean annual precipitation is about 21 inches, and mean annual temperature is about 42 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Haplic Vermudolls

TYPICAL PEDON: Singsaas silty clay loam - on a 2 percent west-facing slope in flax stubble. When described the soil was moist throughout. (Colors are for dry soil unless otherwise stated.)

Ap--0 to 9 inches; dark gray (10YR 4/1) silty clay loam, black (10YR 2/1) moist; weak medium subangular blocky structure parting to weak fine granular; hard, friable, slightly sticky and slightly plastic; few worm casts; few fine and very fine roots; few very fine pores; neutral (pH 6.8); abrupt smooth boundary. (6 to 12 inches thick)

AB--9 to 13 inches; dark grayish brown (10YR 4/2) and brown (10YR 5/3) silty clay loam; black (10YR 2/1) and dark brown (10YR 3/3) moist; moderate medium subangular blocky structure parting to moderate very fine and fine subangular blocky; hard, very friable, slightly sticky and slightly plastic; 60 percent worm casts and worm holes; few fine and very fine roots; many fine pores; neutral (pH 6.8); clear wavy boundary. (0 to 13 inches thick)

Bw--13 to 19 inches; brown (10YR 5/3) and dark grayish brown (10YR 4/2) silty clay loam; brown (10YR 4/3) and very dark grayish brown (10YR 3/2) moist; weak coarse prismatic structure parting to moderate medium and fine subangular blocky; hard, very friable, slightly sticky and slightly plastic; 30 percent worm casts and worm holes; few very fine roots; many fine pores; matrix noncalcareous with few calcareous worm casts; neutral (pH 7.2); clear wavy boundary. (5 to 15 inches thick)

2Bk1--19 to 32 inches; light yellowish brown (2.5Y 6/4) loam; olive brown (2.5Y 4/4) moist; weak coarse prismatic structure parting to moderate medium subangular blocky; hard, friable, slightly sticky and slightly plastic; few worm casts and worm holes; few fine roots; many fine pores; 4 percent pebbles; common fine accumulations of calcium carbonate; violent effervescence; moderately alkaline (pH 8.0); gradual wavy boundary.

2Bk2--32 to 41 inches; light yellowish brown (2.5Y 6/4) loam, yellowish brown (10YR 5/4) moist; weak coarse prismatic structure parting to weak medium and coarse subangular blocky; hard, friable, slightly sticky and slightly plastic; few worm holes; common very fine pores; 3 percent pebbles; common fine accumulations of calcium carbonate; common fine and medium distinct yellowish brown (10YR 5/6) Fe masses and gray (10YR 5/1) Fe depletions; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary. (Combined Bk horizon is 10 to 30 inches thick.)

2C1--41 to 52 inches; light brownish gray (2.5Y 6/2) loam, olive brown (2.5Y 4/4) moist; few fine red (2.5YR 4/6) and common fine and medium prominent yellowish brown (10YR 5/6) Fe masses; massive; hard, friable, slightly sticky and slightly plastic; few worm holes; 4 percent pebbles; common very fine pores; few fine accumulations of calcium carbonate; common fine and medium distinct grayish brown (2.5Y 5/2) Fe depletions; strongly effervescent; moderately alkaline (pH 8.2); gradual wavy boundary.

2C2--52 to 80 inches; light yellowish brown (2.5Y 6/4) loam, light olive brown (2.5Y 5/4) moist; few fine prominent red (2.5YR 4/6) and common fine and medium prominent yellowish brown (10YR 5/6) Fe masses; massive; hard, firm, slightly sticky and slightly plastic; 4 percent pebbles; few very fine pores; common fine and medium distinct light brownish gray (2.5Y 6/2) Fe depletions; strongly effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Brookings County, South Dakota; about 6 miles north and 9 miles east of White, South Dakota; 250 feet west and 1460 feet south of northeast corner of sec. 9, T. 112 N., R. 47 W

RANGE IN CHARACTERISTICS: Depth to free calcium carbonate is 12 to 36 inches. Thickness of the mollic epipedon is 10 to 16 inches. The control section contains about 25 to 35 percent clay and more than 15 percent fine sand or coarser. Most pedons have a silty mantle 10 to 30 inches thick. The A and Bw horizons consist mostly of worm casts and filled worm holes. The mollic epipedon, below the Ap horizon, has over 50 percent by volume of worm casts, worm holes and worm filled holes and the transition to the underlying material has more than 25 percent worm casts, worm holes and worm filled holes.

The Ap horizon has hue of 10YR or 2.5Y, value of 4 or 5 and 2 or 3 moist, and chroma of 1.5 or less. The A horizon is silty clay loam, silt loam or loam. Reaction is neutral or slightly acid.

The AB horizon has colors and textures of the A and Bw horizons.

The Bw horizon has mixed colors with hue of 10YR or 2.5Y, value of 4 to 7 and 2 to 5 moist, and chroma of 1 to 4. It is silty clay loam, silt loam, loam or clay loam and is neutral or slightly alkaline.

Some pedons have a BA horizon.

The 2Bk horizon has hue of 10YR or 2.5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is loam or clay loam. It has few to many worm casts, worm holes and worm filled holes. It has few or common, fine or medium accumulations of carbonate.

The 2C horizons have hue of 2.5Y or 5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is loam or clay loam. It has few or common, faint to prominent mottles. The 2Bk and 2C horizons are slightly alkaline or moderately alkaline.

COMPETING SERIES: There are no other soils in this family.

GEOGRAPHIC SETTING: Singsaas soils are on nearly level to gently undulating ground moraines. Surfaces are plane to convex on slopes of 0 to 9 percent. The Singsaas soils formed in an upper mantle overlying clay loam or loam glacial till. Mean annual air temperature ranges from 38 to 45 degrees F and mean annual precipitation ranges from 20 to 24 inches. Growing season is about 120 to 140 days; average growing season precipitation from 19 to 22 inches; and growing degree days are about 2500 to 2900. Elevation ranges from 890 to 1950 feet above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Barnes, Buse, Oak Lake and Parnell soils. Barnes soils do not have a two story profile and are on similar positions. Buse soils have carbonates within 7 inches of the surface when mixed and are on steeper parts of the landscape. Oak Lake soils are lower lying on the landscape and have saturation with 20 to 40 inches of the surface. Parnell soils contain more than 35 percent clay in the particle size conrol section, have soil saturation to the surface and are in depressions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. Runoff is low to high. Saturated hydraulic conductivity is moderate in the upper mantle and moderately slow in the till. Occasional seasonal high saturation occurs at depths of 40 to 60 inches in years of above normal precipitation.

USE AND VEGETATION: Most areas of Singsaas soils are cultivated. The main crops are corn, soybeans, small grains and alfalfa. Native vegetation is big bluestem, little bluestem, green needlegrass, needleandthread, sideoats grama, and sedges.

DISTRIBUTION AND EXTENT: Northeastern South Dakota and southwestern Minnesota. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota

SERIES ESTABLISHED: Brookings County, South Dakota, 1956.

REMARKS: The Oak Lake series is being re-activated to cover wetter parts of the position on the landscape. Oak Lake would have pachic subgroup class if one was established.

Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of about 13 inches (Ap and AB horizons); cambic horizon - the zone from about 13 to 19 inches (Bw horizon), Verm great group class based on 60 percent worm casts and worm holes in the AB horizon.

ADDITIONAL DATA: NSSL Sample Nos. 84P1065-1070.


National Cooperative Soil Survey
U.S.A.