LOCATION HARCOT IA+MNEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Typic Calciaquolls
TYPICAL PEDON: Harcot loam in a nearly level cultivated field. (Colors are for moist soil unless otherwise stated.)
Apk--0 to 8 inches; black (10YR 2/1) loam, dark gray (10YR 4/1) dry; weak very fine granular structure; friable; violent effervescence, moderately alkaline; clear smooth boundary.
Ak--8 to 14 inches; black (N 2/0) loam, dark gray (10YR 4/1) dry; weak fine granular structure; friable; violently effervescent; moderately alkaline; clear smooth boundary. (Combined thickness of the A horizons is 12 to 18 inches.)
ABk--14 to 20 inches; very dark gray (10YR 3/1) loam, gray (10YR 5/1) dry; weak medium subangular blocky structure; friable; few fine distinct brown (7.5YR 4/4) Fe concentrations; violently effervescent; moderately alkaline; clear smooth boundary. (0 to 7 inches thick)
Bkg--20 to 27 inches; gray (10YR 5/1) loam; weak medium subangular blocky structure; friable; few dark reddish brown (5YR 2/2) concretions (oxides); common fine distinct strong brown (7.5YR 5/6) Fe concentrations; violently effervescent; moderately alkaline; clear wavy boundary. (6 to 14 inches thick)
BC--27 to 33 inches; mixed strong brown (7.5YR 5/6), reddish brown (2.5YR 5/4) and light brownish gray (2.5Y 6/2)loam; weak coarse subangular blocky structure; friable; few dark reddish brown (5YR 2/2) concretions (oxides); strongly effervescent; slightly alkaline; clear smooth boundary. (0 to 8 inches thick)
2C1--33 to 40 inches; pale brown (10YR 6/3) fine sand; single grain; loose; few fine distinct yellowish brown (10YR 5/8) Fe concentrations; slightly effervescent; slightly alkaline (0 to 10 inches thick)
2C2--40 to 60 inches; light brownish gray (2.5Y 6/2) fine sand; single grain; loose; few fine distinct yellowish brown (10YR 5/6) Fe concentrations; slightly effervescent; slightly alkaline
TYPE LOCATION: Worth County, Iowa; about 4 miles west and 3 miles north of Northwood; 160 feet north and 85 feet west of the southeast corner of sec. 11, T. 100 N., R. 21 W.
RANGE IN CHARACTERISTICS: Depth to coarse textured material is 20 to 40 inches. The thickness of the mollic epipedon is 10 to 24 inches. Rock fragmens make up 0 to 5 percent of the upper mantle and 0 to 25 percent of the underlying material.
The A horizons have hue of 10YR or is neutral, value of 2 or 3 and chroma of 0 through 2. It typically is loam but includes clay loam and silt loam. Reaction is slightly alkaline or moderately alkaline.
The ABk horizon has hue of 10YR through 5Y or is neutral, value of 3 and chroma of 0 through 3. It typically is loam but includes clay loam and silt loam. Reaction is moderately alkaline.
The Bkg horizon has hue of 10YR through 5Y; value of 4 or 5; and chroma of 1 or 2. It is loam, clay loam, or sandy clay loam containing 18 to 30 percent clay. Reaction is moderately alkaline.
The BC horizon has hue ranging from 7.5YR through 5Y, value of 4 to 6, and chroma of 2 to 6. It is loam, sandy clay loam, or sandy loam. Reaction is slighlty alkaline or moderately alkaline Sandy loam BC horizons are less than 5 inches thick.
The 2C horizon has hue of 10YR through 5Y; value of 5 or 6; and chroma of 1 to 6. The 2C horizon is loamy fine sand, fine sand, sand, loamy sand or their gravelly analogues. In some pedons, the upper 4 to 12 inches of the 2C horizon contains over 35 percent gravel and cobblestones.
COMPETING SERIES:: These are the competing Arlo series. Arlo soils receive less rainfall and are drier in the soil moisture control section. Exact differentae is pending futher study.
GEOGRAPHIC SETTING: Harcot soils are on stream terraces, flood plains and outwash plains. They typically are on the lower part of the landscape. In some areas, there are a few small depressions. The slopes are nearly level and range from slightly concave to slightly convex. Slope gradients range from 0 to 2 percent. These soils formed in loamy alluvial sediments overlying sand and gravel outwash. Mean annual air temperature ranges from about 45 to 52 degrees F, and mean annual precipitation ranges from about 26 to 34 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Talcot soils and the Biscay, Cylinder, Lawler, Madelia, Marshan, and Tilfer soils. Biscay, Madelia, and Marshan soils have neutral sola and the Madelia soils are silty. Cylinder and Lawler series have less gray B horizons, are somewhat poorly drained, and lack free carbonates in the sola.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: These soils are poorly drained. Runoff is low and they pond in some places. Saturated hydraulic conductivity is 4.23 to 14.11 micrometers per second (.6 to 2.0 inches) in the upper mantle and 141 to 705 micrometers per second (20 to 100 inches) in the underlying material.
USE AND VEGETATION: Where artificially drained, Harcot soils are used for corn and soybeans. Undrained areas are used for pasture or wildlife land. Native vegetation is tall prairie grasses and sedges.
DISTRIBUTION AND EXTENT: MLRA-103. Central and north-central Iowa and possibly adjoining states. Inextensive.
MLRA OFFICE RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Worth County, Iowa, 1972.
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 20 inches (Apk, Ak and ABk horizon); calcic horizon - the zone from about the surface to a depth of 27 inches (Apk, Ak, AB and Bkg horizons).