LOCATION STORLA SDEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mesic
Aeric Calciaquolls
TYPICAL PEDON: Storla loam - from cultivated field. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 6 inches; black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak fine subangular blocky structure; slightly hard, friable; slight effervescence; moderately alkaline; abrupt smooth boundary.
A--6 to 10 inches; black (10YR 2/1) loam, very dark gray (10YR 3/1) dry; weak medium and fine subangular blocky structure; slightly hard, friable; slight effervescence; moderately alkaline; clear wavy boundary. (Combined A horizons 6 to 11 inches thick)
Bk1--10 to 14 inches; black (10YR 2/1) and very dark grayish brown (2.5Y 3/2) loam, very dark gray (10YR 3/1) and olive brown (2.5Y 4/3) dry; weak coarse subangular blocky structure parting to weak medium and fine subangular blocky; slightly hard, friable; common fine accumulations of carbonate; many fine pores; strong effervescence; moderately alkaline; clear wavy boundary.
Bk2--14 to 22 inches; light olive brown (2.5Y 5/3) and dark grayish brown (2.5Y 4/2) loam, light yellowish brown (2.5Y 6/3) and grayish brown (2.5Y 5/2) dry; few fine distinct yellowish brown (10YR 5/6) redox concentrations; weak coarse subangular blocky structure parting to weak fine subangular blocky; slightly hard, friable; many fine and medium accumulations of carbonate; many fine pores; common worm casts; violent effervescence; moderately alkaline; gradual wavy boundary. (Combined Bk horizons 9 to 23 inches thick)
Bkz--22 to 31 inches; light olive brown (2.5Y 5/4) loam, light yellowish brown (2.5Y 6/3) dry; common fine distinct yellowish brown (10YR 5/6) redox and very dark brown (10YR 2/2) redox concentrations; weak coarse subangular blocky structure; slightly hard, friable; few fine nests of salts; few fine concretions (Fe and Mn oxides); many medium accumulations of carbonate; few pebbles; violent effervescence; moderately alkaline; clear wavy boundary. (0 to 15 inches thick)
2C1--31 to 36 inches; light olive brown (2.5Y 5/4) and dark yellowish brown (10YR 4/4) loamy sand, light yellowish brown (2.5Y 6/3) and yellowish brown (10YR 5/4) dry; many fine distinct strong brown (2.5Y 5/6) and very dark brown (10YR 2/2) redox concentrations; single grained; loose; common fine dark concretions (iron and manganese oxides); few medium accumulations of carbonate; strong effervescence; moderately alkaline; gradual wavy boundary.
2C2--36 to 60 inches; light olive brown (2.5Y 5/4) and dark yellowish brown (10YR 4/4) gravelly sand, light yellowish brown (2.5Y 6/3) and yellowish brown (10YR 5/4) dry; single grained; loose; common fine concretions (iron and manganese oxides); strong effervescence; moderately alkaline.
TYPE LOCATION: Union County, South Dakota; 4 miles south and 1 1/2 miles east of Beresford; 380 feet west and 2225 feet north of the southeast corner of sec. 35, T. 95 N., R. 50 W.
RANGE IN CHARACTERISTICS: The mollic epipedon ranges from 7 to 15 inches in thickness. Depth to sand and gravel ranges between 20 and 36 inches and has 20 to 40 percent by volume of gravel. That part of the control section above the sand and gravel is loam, fine sandy loam or sandy loam averaging between 18 and 27 percent clay. Most pedons have carbonate at the surface but some pedons are leached to depths of 6 inches in native grass. The calcium carbonate equivalent ranges between 20 and 40 percent in the calcic horizon.
The A horizon has hue of 10YR or 2.5Y, value of 2 or 3 and 3 or 4 dry, and chroma of 1 or 2. It is loam, silt loam, or fine sandy loam. It is neutral to moderately alkaline.
The Bk and Bkz horizons have hue of 10YR or 2.5Y, value of 2 to 5 and 3 to 7 dry and chroma of 2 to 4. They are loam, sandy loam, or fine sandy loam; and slightly alkaline or moderately alkaline. They have few or common, faint or distinct redox features. Accumulations of carbonate range from few to many. Nests of gypsum and other salts commonly are in the lower Bk horizon of most pedons.
The 2C horizon has hue of 7.5YR, 10YR, or 2.5Y, value of 4 or 5 and 5 to 7 dry, and chroma of 2 to 6. It is loamy sand, gravelly loamy sand, or gravelly sand and slightly alkaline or moderately alkaline.
COMPETING SERIES: There are no other series in the same family.
GEOGRAPHIC SETTING: Storla soils are on nearly level, broad glacial meltwater plains. Slope gradients range from 0 to 2 percent. These soils formed in loamy alluvium overlying glaciofluvial sand and gravel. The mean annual air temperature is 45 to 52 degrees F, and the mean annual precipitation ranges from 18 to 26 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Delmont, Dempster, Dimo, Enet, and Fedora soils. Delmont, Dempster, and Enet soils do not have a calcic horizon and are drier and are on higher parts of the landscape. In addition, Delmont soils have sand and gravel above a depth of 20 inches. Dimo and Fedora soils are on landscapes similar to the Storla soils. Dimo soils do not have a calcic horizon and Fedora soils are coarse-loamy.
DRAINAGE AND PERMEABILITY: Moderately well drained or somewhat poorly drained. Surface runoff is negligible or low depending on slope. Permeability is moderate in the solum and moderately rapid or rapid below. A water table is within 1.5 or 3 feet of the surface in the spring of most years.
USE AND VEGETATION: These soils are cultivated and the principal crops are corn, oats, soybeans, alfalfa, and tame pasture. The native species are big bluestem, little bluestem, green needlegrass, needlandthread, sideoats grama, sedges, and forbs.
DISTRIBUTION AND EXTENT: Southeastern and south-central South Dakota. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Davison County, South Dakota, 1974.
REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 14 inches (Ap, A, and Bk1 horizons); calcic horizon - the zone from 10 to 31 inches (Bk1, Bk2 and Bkz horizons).