LOCATION VIRGIL IL+WI

Established Series
Rev. JCD-SKH-SLE
05/2016

VIRGIL SERIES

The Virgil series consists of very deep, somewhat poorly drained soils on outwash plains, stream terraces, or till plains. These soils formed in loess or other silty material and in the underlying loamy outwash or sandy loam till. Slope ranges from 0 to 6 percent. Mean annual air temperature is about 8.3 degrees C (47 degrees F). Mean annual precipitation is about 890 mm (35 inches).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Udollic Endoaqualfs

TYPICAL PEDON: Virgil silt loam on a northeast facing, 1 percent slope in a cultivated field at an elevation of about 233 meters (765 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 18 cm (0 to 7 inches); black (10YR 2/1) silt loam, grayish brown (10YR 5/2) dry; weak medium granular structure; friable; common fine roots; neutral; abrupt smooth boundary. [18 to 25 cm (7 to 10 inches) thick]

E--18 to 33 cm (7 to 13 inches); dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) silt loam, light brownish gray (10YR 6/2) dry; weak thin platy structure parting to moderate fine granular; friable; many fine roots; few faint black (10YR 2/1) organic coatings on faces of peds and on surfaces along root channels; few fine distinct brown (7.5YR 4/4) masses of oxidized iron-manganese in the matrix; strongly acid; clear smooth boundary. [5 to 20 cm (2 to 8 inches) thick]

Bt1--33 to 43 cm (13 to 17 inches); grayish brown (10YR 5/2) and brown (10YR 5/3) silty clay loam; moderate fine subangular blocky structure; firm; common fine roots; few faint dark grayish brown (10YR 4/2) clay films on faces of peds; common distinct light gray (10YR 7/2) (dry) clay depletions on faces of peds; few fine distinct black (10YR 2/1) iron-manganese concretions throughout; few fine distinct brown (7.5YR 4/4) masses of oxidized iron-manganese and few prominent strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; strongly acid; clear smooth boundary.

Bt2--43 to 64 cm (17 to 25 inches); grayish brown (10YR 5/2) and brown (10YR 5/3) silty clay loam; moderate fine subangular blocky structure; firm; common fine roots; common faint dark grayish brown (10YR 4/2) and grayish brown (10YR 5/2) clay films on faces of peds; common faint light gray (10YR 7/2) (dry) clay depletions on faces of peds; few fine distinct black (10YR 2/1) iron-manganese concretions throughout; few fine distinct brown (7.5YR 4/4) masses of oxidized iron-manganese and prominent strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; strongly acid; gradual smooth boundary.

Btg1--64 to 89 cm (25 to 35 inches); light brownish gray (2.5Y 6/2) silty clay loam; moderate fine and medium subangular blocky structure; firm; few fine roots; many faint grayish brown (2.5Y 5/2) clay films on faces of peds; few distinct light gray (10YR 7/2) (dry) clay depletions on faces of peds; many fine prominent black (10YR 2/1) iron-manganese concretions hroughout; common fine prominent strong brown (7.5YR 5/6) and common fine prominent strong brown (7.5YR 5/8) masses of oxidized iron in the matrix; strongly acid; clear smooth boundary.

Btg2--89 to 112 cm (35 to 44 inches); light brownish gray (2.5Y 6/2) silty clay loam; moderate medium and coarse subangular and angular blocky structure; firm; few fine roots; common faint grayish brown (2.5Y 5/2) clay films on faces of peds; few distinct light gray (10YR 7/2) (dry) clay depletions on faces of peds; many fine prominent black (10YR 2/1) iron-manganese nodules and concretions throughout; many medium prominent brown (7.5YR 4/4) masses of oxidized iron-manganese and strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; moderately acid; clear smooth boundary.

Btg3--112 to 124 cm (44 to 49 inches); grayish brown (2.5Y 5/2) silty clay loam; weak medium and coarse angular blocky structure; firm; few fine roots; few prominent gray (N 5/) clay films on faces of peds; many fine prominent black (10YR 2/1) iron-manganese nodules and concretions throughout; many medium prominent brown (7.5YR 4/4) masses of oxidized iron-manganese and strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; moderately acid; clear smooth boundary. [Combined thickness of the Bt and Btg horizons is 51 to 102 cm (20 to 40 inches)]

2Btg4--124 to 147 cm (49 to 58 inches); grayish brown (2.5Y 5/2) and light brownish gray (2.5Y 6/2) loam; weak coarse angular blocky structure; firm; few prominent dark gray (N 4/) clay films on faces of peds; few fine prominent black (10YR 2/1) iron-manganese concretions throughout; many medium prominent brown (7.5YR 4/4) masses of oxidized iron-manganese and strong brown (7.5YR 5/6) masses of oxidized iron in the matrix; neutral; gradual smooth boundary. [10 to 43 cm (4 to 17 inches) thick]

2C--147 to 152 cm (58 to 60 inches); brown (10YR 4/3) and dark yellowish brown (10YR 4/4) sandy loam; massive; friable; common fine distinct dark gray (10YR 4/1) and gray (10YR 5/1) iron depletions in the matrix; moderately alkaline.

TYPE LOCATION: Stephenson County, Illinois; about 1 mile south of Freeport; 1,346 feet east and 300 feet south of the northwest corner of sec. 8, T. 26 N., R. 8 E.; USGS Freeport East topographic quadrangle; lat. 42 degrees 16 minutes 20 seconds N., and long. 89 degrees 36 minutes 23 seconds W., UTM Zone 16T, 0285052 easting and 4683325 northing; NAD 83.

RANGE IN CHARACTERISTICS:
Thickness of the solum: typically 122 to 152 cm (48 to 60 inches) but ranges from 107 to 178 cm (42 to 70 inches).
Depth to the horizon with more than 40 percent sand: commonly 114 and 127 cm (45 and 50 inches), but ranges from 102 to 152 cm (40 to 60 inches).
Depth to carbonates: 114 to 178 cm (45 to 70 inches)
Particle-size control section (weighted average): 27 to 35 percent clay

A or Ap horizon:
Hue: 10YR
Value: 2 or 3
Chroma: 1 or 2
Texture: silt loam
Reaction: slightly acid to slightly alkaline

E or Eg horizon:
Hue: 10YR
Value: 4 to 6
Chroma: 1 or 2
Texture: silt loam
Reaction: strongly acid to neutral
Other features: Some pedons have redoximorphic features.

Bt and/or Btg horizons:
Hue: 10YR, 2.5Y or 5Y
Value: 4 to 6
Chroma: 2 to 4
Texture: silty clay loam
Clay content: averages 27 to 35 percent
Sand content: averages less than 10 percent
Reaction: strongly acid to slightly acid, but some pedons range to slightly alkaline in the lower part.
Redoximorphic features have hue of 7.5YR, 10YR, or 2.5Y, value of 4 or 5, and chroma of 2 to 8.

2Bt, 2Btg, 2BC, and/or 2BCg horizons:
Hue: 10YR, 2.5Y or 5Y
Value: 4 to 6
Chroma: 2 to 8
Texture: loam, sandy loam, clay loam, silt loam or silty clay loam
Average sand content: 20 to 60 percent
Content of rock fragments: less than 10 percent
Redoximorphic features: It has redoximorphic features throughout. It typically has low chroma colors in the matrix and higher chroma in the redoximorphic features.
Reaction: moderately acid to slightly alkaline

2C or 2Cg horizon:
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 2 to 8
Texture: sandy loam, loam, sandy clay loam, loamy sand, clay loam, silt loam or is sandy loam till
Sand content: 20 to 80 percent
Content of rock fragments: less than 15 percent
Reaction: slightly acid to moderately alkaline

COMPETING SERIES: These are the Atterberry, Bethalto, Canoe, Curran, Emery, Franklin, Koszta, Millbrook, Mulvey, and Wauconda series. Atterberry, Bethalto, Canoe, and Koszta series average less than 20 percent sand in the lower part of the series control section. Curran soils average less than 27 percent clay in the middle part of the series control section. Emery soils do not have a layer in the lower part of the series control section that has more than 25 percent sand. Millbrook, Franklin, and Wauconda soils have horizons with more than 10 percent sand within a depth of 102 cm (40 inches). Mulvey soils average less than 15 percent clay and greater than 15 percent gravel in the lower part of the series control section.

GEOGRAPHIC SETTING: Virgil soils are nearly level or gently sloping low broad summits on outwash plains, stream terraces, and till plains. Slope ranges from 0 to 6 percent. These soils formed in 102 to 152 cm (40 to 60 inches) of loess or other silty sediments and in the underlying loamy outwash or sandy loam till. The dominant clay mineral in the loess is smectite, and in the outwash or till is illite. Summers are hot and winters are cold. Mean annual air temperature ranges from 6.7 to 12.2 degrees C (44 to 54 degrees F). Mean annual precipitation ranges from 760 to 1070 mm (30 to 42 inches). Frost-free days range from 120 to 190 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Batavia, Drummer, Elburn, Emery, Harvard, Kendall, Millbrook, Plano, St. Charles, and Thorp soils. The well drained Batavia soils are on adjacent, slightly higher parts of the landscape. The poorly drained Drummer soils are on lower parts of the landscape and have a mollic epipedon. Elburn soils have a mollic epipedon and are on similar parts of the landscape nearby but generally are on broad landscape areas farther from the drainageways. Emery soils are on adjacent dissected till plains and average less than 20 percent sand in the lower part of the series control section. The well drained Harvard soils are on adjacent, slightly higher parts of the landscape and formed in loess less than 102 cm (40 inches) thick. Kendall soils are on similar parts of the landscape nearby but generally are adjacent to or nearer the drainageways and do not have a dark colored surface layer. Millbrook soils are on similar parts of the stream terraces and outwash plains where the loess is thinner. The well drained Plano soils have a mollic epipedon and are on adjacent, slightly higher parts of the landscape. The well drained St. Charles soils are on adjacent, slightly higher parts of the landscape and do not have dark colored surface layer. The poorly drained Thorp soils have a mollic epipedon and are on lower parts of the landscape.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. An intermittent apparent high water table is at a depth of 31 to 61 cm (1.0 to 2.0 feet) below the surface in most years. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers per second) in the upper part of the solum and high (14.11 to 42.34 micrometers per second) in the lower part. Permeability is moderate in the upper part of solum and ranges moderate to moderately rapid in the lower part. The potential for surface runoff is low to medium as related to slope.

USE AND VEGETATION: Most areas are cultivated. Corn, soybeans, small grain, and forages for hay are the principal crops. Native vegetation is mixed grasses and trees.

DISTRIBUTION AND EXTENT: Northern Illinois and southern Wisconsin. LRR's K and M, MLRA's 95A, 95B, 108A, 108B and 115C. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana

SERIES ESTABLISHED: Kendall County, Illinois, 1941.

REMARKS: A gravelly substratum phase is recognized. This soil will be investigated during MLRA update activities. Possibly a new series will be developed.

Diagnostic horizons recognized in this pedon are:
Ochric epipedon -from a depth of 0 to 33 cm (0 to 13 inches) (Ap and E horizons)
Albic horizon--from a depth of 18 to 33 cm (7 to 13 inches) (E horizon)
Argillic horizon--from a depth of 33 to 150 cm (13 to 59 inches) (Bt1, Bt2, Btg1, Btg2, Btg3, 2Btg4, and 2C horizons)
Aquic conditions--endosaturation implied by redoximorphic features present in the zone from 33 to 200 cm

National Cooperative Soil Survey
U.S.A.