LOCATION ALLIVAR SDEstablished Series
TAXONOMIC CLASS: Sandy, mixed, frigid Calcic Hapludolls
TYPICAL PEDON: Allivar sandy loam, on a plane slope of less than 1 percent in pasture. When described the soil was moist throughout. (Colors are for dry soil unless otherwise stated).
Ap--0 to 6 inches; very dark gray (10YR 3/1) sandy loam, black (10YR 2/1) moist; weak fine and medium subangular blocky structure parting to moderate fine and medium granular; slightly hard; friable; common very fine roots throughout; common fine pores; neutral (pH 6.8); abrupt smooth boundary. (5 to 10 inches thick)
Bw--6 to 15 inches; dark grayish brown (10YR 4/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak coarse prismatic structure parting to moderate fine and medium subangular blocky; slightly hard; friable; common very fine roots throughout; common fine pores; common distinct patchy black (10YR 2/1) moist; organic coats throughout;
2 percent subrounded gravel; slightly alkaline (pH 7.4); gradual smooth boundary. (5 to 13 inches thick)
2C1--15 to 40 inches; light brownish gray (10YR 6/2) sand, dark grayish brown (10YR 4/2) moist; single grain; loose; many carbonate coats on sand and gravel; 10 percent subrounded gravel; strongly effervescent; moderately alkaline (pH 8.2); gradual smooth boundary.
2C2--40 to 50 inches; light brownish gray (2.5Y 6/2) sand, dark grayish brown (2.5Y 4/2) moist; common fine and medium distinct yellowish brown (10YR 5/6) moist Fe masses; single grain; loose; few prominent patchy black (7.5YR 2/1) moist and dark reddish brown (5YR 3/4) moist; manganese or iron-manganese stains throughout; 2 percent subrounded gravel; strongly effervescent; strongly alkaline (pH 8.5); clear smooth boundary.
2C3--50 to 80 inches; brown (10YR 6/3) very gravelly sand, pale brown (10YR 4/3) moist; single grain; loose; carbonate coats on undersides of gravel; ; 45 percent subrounded gravel; strongly effervescent; strongly alkaline (pH 8.5).
TYPE LOCATION: Brookings County, South Dakota, located about 2470 feet north and 1660 feet east of the SW corner of section 24, T. 111 N., R. 51 W, Bruce, South Dakota topographic quadrangle, lat. 44 degrees 24 minutes 20 seconds N. and long. 96 degrees 54 minutes 01 second W., NAD27.
RANGE IN CHARACTERISTICS: The depth to sand and gravel ranges from 14 to 25 inches. The particle size control section averages less than 35 percent gravel by volume. The thickness of the mollic epipedon ranges from 7 to 20 inches thick. When it is 16 or more inches thick, it has a sandy particle size in the major part.
The Ap or A horizon has hue of 10YR, value of 3 or 4 and 2 or 3 moist, and chroma of 1 or 2. It is sandy loam, coarse sandy loam, loam, or fine sandy loam. It has 0 to 10 percent gravel. It is slightly acid to slightly alkaline. Some pedons have an AB horizon.
The Bw horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 4 to 5 and 2 to 5 moist, and chroma of 1 to 4. It is sandy loam, coarse sandy loam, loam, or fine sandy loam. It is loamy sand in the lower part of some pedons. It has 0 to 10 percent gravel. It is slightly acid to moderately alkaline.
Some pedons have a BC or Bk horizon less than 5 inches thick.
The 2C horizon has hue of 7.5YR, 10YR, or 2.5YR, value of 4 to 7 and 3 to 6 moist, and chroma of 2 to 6. It is sand, coarse sand, loamy sand, loamy coarse sand, or their gravelly, very gravelly, or extremely gravelly analogues.
COMPETING SERIES: These are the Arvilla, Binford, Mosford and Sverdrup series in the same family. Arvilla, Sverdrup and Mosford soils do not have a soil saturation in the series control section. Binford soils have sand and gravel 2C horizons that have more than 20 percent shale in the 0.1 to 76 mm fraction.
GEOGRAPHIC SETTING: Allivar soils are on nearly level flood plains. They formed in alluvium over stratified sand and gravel. Slopes are plane or convex and range from 0 to 2 percent. Elevations range from 1000 to 2350 feet above sea level. Mean annual precipitation is 20 to 24 inches. The frost-free period is 120 to 140 days. Mean annual air temperature ranges from 40 to 45 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Divide, Fordtown, Marysland, Maddock, and Renwash soils. Divide and Marysland soils have a calcic horizon within a depth of 16 inches. They are on in slightly concave areas and lower positions of the landscape. Fordtown and Renwash soils have more than 18 percent clay in the upper part of the series control section. Maddock soils are dominated by fine sand and have less than 2 percent gravel in the particle size control section. They are on slightly higher parts of the landscape.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is very low. Permeability is moderately rapid in the upper part and rapid or very rapid in the underlying material. A seasonal high water table is at a depths of 3.5 to 6 feet from March to June in most years.
USE AND VEGETATION: Most ares are cultivated to corn and hay. Native grasses are needleandthread, little bluestem, sideoats grama, and blue grama.
DISTRIBUTION AND EXTENT: Northeastern South Dakota (MLRA 102A). The series is of minor extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Brookings County, South Dakota, 1995.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of about 15 inches (Ap and Bw horizons).