LOCATION PARMOD ILEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argiudolls
TYPICAL PEDON: Parmod silt loam - on an east-facing convex slope of 3 percent in a cultivated field at an elevation of 260 meters (854 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 18 cm (0 to 7 inches); very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry; moderate very fine and fine granular structure; friable; common very fine roots; neutral; clear smooth boundary. [15 to 30 cm (6 to 12 inches) thick]
AB--18 to 30 cm (7 to 12 inches); very dark grayish brown (10YR 3/2) silt loam, grayish brown (10YR 5/2) dry; moderate very fine and fine subangular blocky structure parting to weak fine granular; friable; common very fine roots; neutral; clear smooth boundary. [0 to 15 cm (0 to 6 inches) thick]
Bt1--30 to 48 cm (12 to 19 inches); brown (10YR 4/3) silty clay loam; moderate fine and medium subangular blocky structure; friable; common very fine roots; few distinct very dark grayish brown (10YR 3/2) organic coatings on faces of peds and in pores; few distinct dark brown (10YR 3/3) clay films on faces of peds; neutral; clear smooth boundary. [0 to 25 cm (0 to 10 inches) thick]
2Bt2--48 to 66 cm (19 to 26 inches); brown (7.5YR 4/4) clay loam; moderate medium prismatic structure parting to moderate medium subangular blocky; friable; common very fine roots; few distinct very dark grayish brown (10YR 3/2) organic coatings on faces of peds and in pores; few distinct brown (7.5YR 4/3) and dark brown (7.5YR 3/3) clay films on faces of peds; 2 percent gravel; neutral; clear smooth boundary.
2Bt3--66 to 86 cm (26 to 34 inches); brown (7.5YR 4/4) clay loam; weak medium prismatic structure parting to moderate medium subangular blocky; friable; very few very fine roots; few distinct very dark grayish brown (10YR 3/2) organic coatings in root channels and in pores; few distinct brown (7.5YR 4/3) clay films on faces of peds; 2 percent gravel; neutral; clear smooth boundary. [Combined thickness of the 2Bt horizons is 30 to 61 cm (12 to 24 inches).]
2BC--86 to 97 cm (34 to 38 inches); brown (7.5YR 5/4) loam; weak medium and coarse subangular blocky structure; firm; common very fine roots; very few distinct very dark grayish brown (10YR 3/2) organic coatings in root channels and in pores; 5 percent gravel; strongly effervescent; slightly alkaline; clear smooth boundary. [0 to 15 cm (0 to 6 inches) thick]
2C--97 to 152 cm (38 to 60 inches); brown (7.5YR 5/4) loam; massive; firm; common very fine roots; few fine and medium distinct strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; 6 percent gravel; very strongly effervescent; moderately alkaline.
TYPE LOCATION: Boone County, Illinois about 4 km (2 1/2 miles) south and 7.6 km (4 3/4 miles) east of Poplar Grove; 123 m (405 feet) north and 259 m (850 feet) west of the southeast corner of sec. 35, T. 45 N., R. 4 E.; USGS Garden Prairie topographic quadrangle; lat. 42 degrees 19 minutes 44 seconds N. and long. 88 degrees 43 minutes 42 seconds W., NAD 27; UTM Zone 16, 357595 easting and 4687739 northing, NAD 83.
RANGE IN CHARACTERISTICS: The depth to the base of soil development ranges from 61 to 102 cm (24 to 40 inches). The depth to horizons with greater that 15 percent sand is less than 51 cm (20 inches). The depth to carbonates ranges from 51 to 102 cm (20 and 40 inches). The thickness of the mollic epipedon commonly ranges from 25 to 46 cm (10 to 18 inches)
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The Ap, A, or AB horizon has hue of 10YR, value of 2 or 3, and chroma of 1 to 3. It is silt loam or loam. It is moderately acid to neutral. Gravel content ranges from 0 to 4 percent.
The Bt, 2Bt, or 2BC horizon has hue of 10YR or 7.5YR; value of 4 or 5; and chroma of 3 to 6. It is dominantly clay loam or loam, but ranges to silty clay loam in the upper part where the silt cap is at the maximum thickness. It is moderately acid to neutral in the upper part and is slightly acid to slightly alkaline in the lower part. The calcium carbonate equivalent ranges from 0 to 20 percent. Gravel content ranges from 0 to 10 percent.
The C or 2C horizon has hue of 10YR or 7.5YR; value of 4 to 6; and chroma of 3 to 6. It is loam or sandy loam. Reaction is slightly alkaline or moderately alkaline, and carbonates are present. The calcium carbonate equivalent ranges from 15 to 40 percent. Gravel content ranges from 3 to 15 percent.
COMPETING SERIES: These are the Atkinson, Burchard, Calmar, Cokato, Cresco, Cresent, Durand, Friesland, Griswold, Hitt, Jasper, Joslin, Keosauqua, Kishwaukee, Marbletown, Moingona, Morrill, Nuxmaruhanixete , Pana, Penfield, Reedslake, Ringwood, Rockton, Schoolcraft, Shelby, Sibleyville, Velma, and Winnebago series. Atkinson, Calmar, Hitt, Marbletown, Rockton, and Sibleyville soils have a lithic or paralithic contact at depths less than 152 cm (60 inches). Burchard, Cokato, Reedslake, and Shelby soils average more than 20 percent clay in the lower part of the series control section. Cresco, Durand, Joslin, Keosauqua, Nuxmaruhanixete, Pana, Velma, and Winnebago soils are more than 102 cm (40 inches) to the base of soil development. Cresent, Kishwaukee, and Schoolcraft soils average more than 60 percent sand in the lower part of the series control section. Friesland and Morrill soils are more than 102 cm (40 inches) to carbonates. Griswold and Ringwood soils average less than 15 percent clay in the lower part of the series control section. Jasper, Moingona, and Penfield soils have one or more subhorizons within the series control section dominated by a single grade of sand.
GEOGRAPHIC SETTING: Parmod soils are on till plains and moraines. Slope ranges from 2 to 10 percent. The soils formed in as much as 51 cm (20 inches) of loess or other silty material and in the underlying loamy till. The mean annual air temperature ranges from 7 to 11 degrees C (45 to 52 degrees F), mean annual precipitation ranges from 762 to 1016 mm (30 to 40 inches), frost free days range from 140 to 180 days, and the elevation ranges from 207 to 311 m (679 to 1020 feet) above sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Drummer, Elburn, Geryune, Lismod, and Pella soils. Drummer and Pella soils are poorly drained and are in depressions and drainageways. Elburn and Lismod soils are somewhat poorly drained and are on lower less sloping landform positions. Geryune soils are moderately well drained and are on similar landform positions nearby that have a thicker mantle of loess.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for surface runoff is low or medium. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers per second). Permeability is moderate.
USE AND VEGETATION: Largely cropped to corn and soybeans. Small grain and legume hay are also grown. Native vegetation was tall prairie grass.
DISTRIBUTION AND EXTENT: Northern Illinois. These soils are of small extent in MLRA 95B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: McHenry County, Illinois, 1996. Parmod is a name derived from the Parr series and a moderate permeability class.
REMARKS: Diagnostic features and horizons recognized in this pedon are: mollic epipedon - 0 to 30 cm (0 to 12 inches) (Ap and AB horizons); argillic horizon - 30 to 86 cm (12 to 34 inches) (Bt1, 2Bt2, and 2Bt3 horizons); discontinuity at a depth of 48 cm (19 inches) - the contact between the Bt1 and 2Bt2 horizons; udic moisture regime.