LOCATION PILOT GROVE        MN
Established Series
Rev. TCJ-AGG-TWN
01/2006

PILOT GROVE SERIES


The Pilot Grove series consists of very deep, somewhat excessively drained soils that formed in 40 to 60 inches of loamy and sandy outwash sediments over loamy glacial till or loamy stratified sediment. They are on moraines, till plains or kames. They have moderately rapid permeability in the upper part, rapid or very rapid permeability in sandy subsoil and moderate permeability in the underlying material. Slope ranges from 3 to 40 percent. Mean annual precipitation is about 28 inches. Mean annual air temperature is about 50 degrees F.

TAXONOMIC CLASS: Sandy, mixed, mesic Typic Hapludolls

TYPICAL PEDON: Pilot Grove sandy loam, with a convex 7 percent slope, on a glacial moraine, in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 9 inches; very dark brown (10YR 2/2) sandy loam, dark grayish brown (10YR 4/2) dry; weak fine subangular blocky structure; very friable; common very fine roots; about 8 percent gravel; slightly acid; abrupt smooth boundary. (7 to 12 inches thick)

Bw--9 to 17 inches; brown (10YR 4/3) sandy loam; grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; common dark brown (10YR 3/3) streaks on faces of peds; very friable; common very fine roots; about 7 percent gravel; slightly acid; clear wavy boundary. (3 to 14 inches thick)

2BC--17 to 21 inches; dark yellowish brown (10YR 4/4) loamy sand; single grain; loose; about 5 percent gravel; neutral; gradual wavy boundary. (0 to 15 inches thick)

2C1--21 to 36 inches; brown (10YR 5/3) sand; single grain; loose; few fine distinct yellowish brown (10YR 5/8) iron concentrations; about 8 percent gravel; strongly effervescent; slightly alkaline; gradual wavy boundary. (0 to 30 inches thick)

2C2--36 to 58 inches; yellowish brown (10YR 5/4); gravelly coarse sand; single grain; loose; about 15 percent gravel; strongly effervescent; slightly alkaline; gradual wavy boundary. (0 to 30 inches thick)

3C3--58 to 80 inches; yellowish brown (10YR 5/4) loam; massive with some horizontal planes; friable; few fine prominent strong brown (7.5YR 5/8) iron concentrations; common and fine dark yellowish brown (10YR 3/4) manganese concentrations; few masses of calcium carbonate; about 5 percent gravel; strongly effervescent; slightly alkaline.

TYPE LOCATION: Faribault County, Minnesota; about 4 miles east of Pilot Grove; located about 2,315 feet south and 1,280 feet east of the northwest corner of section 25, T. 101 N., R. 28 W.; USGS Pilot Grove topographic quadrangle; lat. 43 degrees 31 minutes 28 seconds N. and long. 94 degrees 08 minutes 33 seconds W., NAD 83.

RANGE IN CHARACTERISTICS: Depth to carbonates is 12 to 40 inches. Depth to glacial till ranges from 40 to 60 inches. The loamy mantle is 10 to 25 inches thick. The thickness of the mollic epipedon ranges from 7 to 20 inches. The content of gravel, by volume, ranges from 0 to 15 percent in the upper loamy mantle, 10 to 35 percent in the sandy sediment, and 2 to 8 percent in the underlying till. Some pedons have thin subhorizons with more than 35 percent gravel. Cobbles range from 0 to 10 percent and stones range from 0 to 5 percent throughout.

The Ap or A horizon has hue of 10YR, value of 2 or 3 and chroma of 1 or 2. It is sandy loam, coarse sandy loam or loam. It is neutral to moderately acid.

The Bw horizon has hue of 10YR or 7.5YR, value of 3 or 4, and chroma of 3 or 4. It is sandy loam, coarse sandy loam, or loam averaging less than 18 percent clay. It is moderately acid to neutral.

The 2Bw horizon, when present, has hue of 10YR or 7.5YR, value of 3 or 4, and chroma of 2 to 4. It is loamy coarse sand, coarse sand, loamy sand, sand or their gravelly analogs. It is moderately acid to neutral.

The 2BC, when present, has hue of 10YR or 2.5Y, value of 3 to 5 and chroma of 3 or 4. It is loamy coarse sand, coarse sand, loamy sand or their gravelly analogs. It is slightly acid to slightly alkaline.

Some pedons have a 2Bk horizon. Properties are similar to the 2BC horizon but the reaction is slightly alkaline or moderately alkaline. Calcium carbonate coats are common on the bottom side of sand grains and pebbles.

The 2C horizon has hue of 10YR or 2.5Y, value of 4 to 7 and chroma of 3 to 6. It is coarse sand, sand or their gravelly analogues. It is slightly alkaline or moderately alkaline.

Some pedons have a 3BC horizon that has coarse and extremely coarse prismatic primary structure. Other properties are similar to the 3C horizon.

The 3C horizon has hue of 10YR or 2.5Y, value of 4 or 5 and chroma of 2 to 4. In MLRA 103, it is loam, sandy loam, clay loam or stratified silt loam, silty clay loam or very fine sandy loam with moist bulk density of 1.4 to 1.6 g/cc. It is typically friable when moist. It is slightly alkaline or moderately alkaline. In MLRA 107, it is loam or clay loam with moist bulk density of 1.6 to 1.8 g/cc. It is typically firm when moist. It is slightly alkaline or moderately alkaline.

COMPETING SERIES: These are the Buckney, Burkhardt, Dickman, Estherville, Mishawaka and Round Lake series. Buckney, Burkhardt, Dickman, Estherville, and Mishawaka soils do not have loamy glacial till or stratified loamy material in the lower third of the series control section. Round Lake soils have a frequently saturated zone in the lower third of the series control section.

GEOGRAPHIC SETTING: Pilot Grove soils have convex slopes ranging from 3 to 40 percent. They formed in 40 to 60 inches of loamy and sandy outwash sediments over loamy glacial till. They are on moraines, till plains or kames. Mean annual air temperature is about 45 to 55 degrees F. Mean annual precipitation is about 25 to 32 inches. Frost free period ranges from 124 to 190 days. Elevation ranges from 700 to 1,600 feet above sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Estherville, Hawick and Zenor soils and many other soils formed entirely in glacial till.

DRAINAGE AND PERMEABILITY: Pilot Grove soils are somewhat excessively drained. Runoff is very low to medium. Permeability is moderately rapid in the upper part, rapid or very rapid permeability in sandy subsoil and moderate permeability in the underlying glacial till.

USE AND VEGETATION: Most areas are cultivated. The principal crops are corn, soybeans, grain, and hay. Native vegetation is mixed tall and short grass prairie including big bluestem, little bluestem, indiangrass and switchgrass among others.

DISTRIBUTION AND EXTENT: LRR M. MLRA 103 and MLRA 107 encompassing parts of south-central Minnesota and northwestern and central Iowa. The series is minor in extent.

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

SERIES ESTABLISHED: Woodbury County, Iowa, 2003

REMARKS:
Diagnostic horizons recognized in this pedon include: mollic epipedon-the zone from the surface to 9 inches (Ap horizons); cambic horizon-the zone from 9 to 17 inches (Bw horizon); udic moisture regime.

This soil previously was correlated as Estherville or Hawick when occurring as a component in till-outwash complexes in morainic landforms in MLRA 103. The 3C horizon range in characteristics was broadened to include the till properties of MLRA 107 with this revision.


National Cooperative Soil Survey
U.S.A.