LOCATION PENFIELD ILEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argiudolls
TYPICAL PEDON: Penfield loam - on a west facing 3 percent slope in a cultivated field at an elevation of about 203 meters (685 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 25 cm (0 to 10 inches); very dark grayish brown (10YR 3/2) loam, brown (10YR 5/3) dry; moderate fine granular structure; friable; slightly acid; clear smooth boundary. [ 18 to 31 cm (7 to 12 inches) thick]
Bt1--25 to 36 cm (10 to 14 inches); brown (10YR 4/3) clay loam; moderate medium subangular blocky structure parting to moderate very fine subangular blocky; friable; common distinct very dark grayish brown (10YR 3/2) organo-clay films on faces of peds; neutral; clear smooth boundary.
Bt2--36 to 51 cm (14 to 20 inches); dark yellowish brown (10YR 4/4) clay loam; moderate fine prismatic structure parting to moderate very fine angular blocky; firm; many distinct dark brown (10YR 3/3) organo-clay films on faces of peds; neutral; clear smooth boundary.
Bt3--51 to 79 cm (20 to 31 inches); yellowish brown (10YR 5/4) clay loam; moderate medium prismatic structure parting to moderate medium angular blocky; firm; many distinct dark brown (10YR 3/3) organo-clay films on faces of peds; 5 percent fine gravel; neutral; abrupt smooth boundary.
Bt4--79 to 112 cm (31 to 44 inches); 80 percent dark yellowish brown (10YR 4/4) sandy clay loam and 20 percent yellowish brown (10YR 5/6) fine sandy loam; moderate coarse prismatic structure parting to weak coarse angular blocky; friable; common distinct dark brown (10YR 3/3) organo-clay films on faces of peds; 5 percent fine gravel; neutral; clear smooth boundary.
Bt5--112 to 130 cm (44 to 51 inches); yellowish brown (10YR 5/4) sandy clay loam; weak coarse prismatic structure parting to weak coarse angular blocky; friable; common distinct dark brown (10YR 3/3) organo-clay films on faces of peds; common medium black (7.5YR 2.5/1) weakly cemented iron-manganese nodules throughout; common medium distinct light brownish gray (10YR 6/2) iron depletions in the matrix; common medium distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; neutral; clear smooth boundary.
Btg--130 to 155 cm (51 to 61 inches); 60 percent light brownish gray (10YR 6/2) and 40 percent yellowish brown (10YR 5/6) sandy clay loam; weak coarse prismatic structure parting to weak coarse angular blocky; friable; common distinct very dark gray (10YR 3/1) organo-clay films along root channels and pores; common distinct dark grayish brown (10YR 4/2) clay films on faces of peds; neutral; clear smooth boundary. [Combined thickness of the Bt and Btg horizons is 31 to 140 cm (12 to 55 inches)].
BCt--155 to 183 cm (61 to 72 inches); strong brown (7.5YR 5/6) stratified fine sandy loam and sandy clay loam; weak coarse angular blocky structure; friable; common distinct very dark gray (10YR 3/1) organo-clay films on the surfaces along root channels and pores; common distinct dark grayish brown (10YR 4/2) clay films on faces of peds; common medium prominent light brownish gray (10YR 6/2) iron depletions in the matrix; common medium distinct yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; neutral; clear smooth boundary. [ 23 to 33 cm (9 to 13 inches)]
C--183 to 203 cm (72 to 80 inches); yellowish brown (10YR 5/4 and 5/6) fine sandy loam; massive; very friable; neutral.
TYPE LOCATION: Champaign County, Illinois; about 9.5 miles south and 2 miles west of Penfield, Illinois; 910 feet south and 465 feet west of the northeast corner of sec. 30, T. 20 N., R. 14 W.; USGS Royal topographic quadrangle; lat. 40 degrees, 10 minutes, 06 seconds N., and long. 87 degrees, 58 minutes, 50 seconds W.; NAD27; UTM Zone 16, 0416502 easting and 4446905 northing, NAD 83.
RANGE IN CHARACTERISTICS: The depth to the base of the argillic horizon is greater than 61 cm (24 inches). The depth to the base of soil development is greater than 90 cm (35 inches). The mollic epipedon ranges from 10 to 20 inches thick. The depth to carbonates, where present, ranges from 90 cm (35 inches) to more than 203 cm (80 inches). The particle-size control section averages between 20 and 32 percent clay and between 15 and 55 percent fine sand or coarser.
The Ap or A horizon has hue of 10YR, value of 2 or 3, and chroma of 1 to 3. It is loam, silt loam, or fine sandy loam. Reaction ranges from moderately acid to neutral.
Some pedons have a BA horizon. It has hue of 10YR or 7.5YR, value of 4 or 5, and chroma of 3 to 6. It is loam, silt loam, or fine sandy loam. Reaction is strongly acid to neutral.
The Bt or Btg horizon has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 3 to 8 in the upper part and chroma of 2 to 6 in the lower part. It is clay loam, sandy clay loam, sandy loam, loam, silt loam or silty clay loam. Clay content ranges from 20 to 32 percent and sand content ranges from 15 to 55 percent. It has less than 5 percent rock fragments. Reaction is strongly acid to neutral.
In some pedons, the BCt, BC, and/or C horizon is within a depth of 60 inches and is part of the series control section. The BCt or BC horizon has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 2 to 6. Redoximorphic features are present. It is fine sandy loam, sandy loam, very fine sandy loam, loam, sandy clay loam, or clay loam. Clay content ranges from 12 to 32 percent clay and sand content ranges from 45 to 65 percent. It has less than 15 percent rock fragments. Reaction is moderately acid to slightly alkaline. Some pedons have carbonates.
The C horizon has hue of 10YR or 7.5YR, value of 4 to 6, and chroma of 1 to 6. It is stratified sandy clay loam, silt loam, loam, very fine sandy loam, fine sandy loam, sandy loam, loamy sand, loamy fine sand, fine sand, and sand. Clay content ranges from 5 to 20 percent. Sand content typically ranges from 45 to 70 percent, but individual subhorizons can range from 15 to 90 percent sand. It has less than 15 percent rock fragments. It is neutral to moderately alkaline. Some pedons have carbonates.
COMPETING SERIES: These are the Atkinson, Burchard, Cokato, Cresent, Friesland, Griswold, Hitt, Jasper, Joslin, Kishwaukee, La Rose, Marbletown, Morrill, Parmod, Reedslake, Ringwood, Rockton, Shelby, Sibleyville, Winnebago, and Wyanet series. Atkinson, Hitt, Marbletown, Rockton, and Sibleyville soils have a lithic or paralithic contact within a depth of 60 inches. Burchard soils have carbonates within a depth of 35 inches. Cokato, Friesland, Reedslake, and Wyanet soils average less than 45 percent sand in the lower part of the series control section. Cresent, soils average more than 70 percent sand in the lower part of the series control section. Winnebago soils have hue redder than 7.5YR in some part of the argillic horizon. Griswold, La Rose and Parmod, soils are less than 35 inches to the base of soil development. Jasper and Morrill soils do not have redoximorphic features in the lower part of the series control section. Joslin and Shelby soils have more than 20 percent clay in the lower part of the series control section. Kishwaukee and Ringwood, soils have more than 15 percent gravel in the lower part of the series control section.
GEOGRAPHIC SETTING: Penfield soils formed in 0 to 22 inches of loess and in the underlying loamy stratified outwash on outwash plains, till plains, and glacial lake plains of Wisconsinan Age. Slopes range from 0 to 10 percent. Mean annual temperature ranges from 8 to 12 degrees C (46 to 54 degrees F), mean annual precipitation ranges from 740 to 990 mm (29 to 39 inches), frost free period ranges from 160 to 180 days, and elevation ranges from 650 to 850 feet above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brenton, Drummer, Elliott, La Hogue, Pella, and Selma soils. The somewhat poorly drained Brenton and La Hogue soils are on lower landscape positions. The poorly drained Drummer, Pella, and Selma soils are in depressional areas below the Penfield soils. The somewhat poorly drained Elliott soils formed in clayey till and are on lower landscape positions.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for surface runoff ranges from negligible to medium. Saturated hydraulic conductivity is moderately high to high (4.23 to 14.11 micrometer per second). Permeability is moderate. These soils have an intermittent apparent seasonal high water table at a depth of 107 to 183 cm (3.5 to 6 feet) between February and April in most years.
USE AND VEGETATION: Soils are cultivated. Corn, soybeans, wheat, and oats are principal crops. Native vegetation was tall prairie grasses, chiefly Big Blue stem.
DISTRIBUTION AND EXTENT: East-central and northern Illinois. The series is of small extent in MLRAs 108A, 108B, and 110.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Champaign County, Illinois, 1998. Penfield is the name of a town in eastern Champaign County.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon - the zone from the surface to a depth of 10 inches (Ap horizon);
argillic horizon - the zone from about 10 inches to 72 inches (Bt ,Btg, and BCt horizons);
udic moisture regime; mesic temperature regime.