LOCATION STOY IL+IN
Established Series
Rev. GOW-JBF-TJE
06/2023
STOY SERIES
The Stoy series consists of very deep, somewhat poorly drained soils that formed in loess on uplands. Slope ranges from 0 to 10 percent. Mean annual precipitation is about 1067 mm (42 inches), and mean annual air temperature is about 13 degrees C (56 degrees F).
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Fragiaquic Hapludalfs
TYPICAL PEDON: Stoy silt loam, on a 3 percent slope in a cultivated field at an elevation of about 119 meters (389 feet) above mean sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 15 cm (0 to 6 inches); brown (10YR 4/3) silt loam; weak fine granular structure; friable; many roots; few fine iron-manganese concretions throughout; very strongly acid; abrupt smooth boundary. [15 to 25 cm (6 to 10 inches) thick]
E1--15 to 23 cm (6 to 9 inches); mixed light yellowish brown (10YR 6/4) and yellowish brown (10YR 5/4) silt loam; weak thin platy structure parting to weak fine granular; friable; common roots; common very dark grayish brown (10YR 3/2) organic stains; few medium distinct light brownish gray (10YR 6/2) iron depletions in the matrix; many fine iron-manganese concretions throughout; very strongly acid; clear smooth boundary.
E2--23 to 33 cm (9 to 13 inches); yellowish brown (10YR 5/4) silt loam; weak fine and medium granular structure; friable; common roots; common medium distinct light brownish gray (10YR 6/2) iron depletions and yellowish brown (10YR 5/6) masses of oxidized iron in the matrix; many fine iron-manganese concretions throughout; very strongly acid; clear smooth boundary. [Combined thickness of the E horizon is 0 to 25 cm (10 inches).]
BE--33 to 41 cm (13 to 16 inches); yellowish brown (10YR 5/6) silty clay loam; weak fine and medium subangular blocky structure; friable; common roots; few medium prominent light brownish gray (10YR 6/2) iron depletions in the matrix; many fine iron-manganese concretions throughout; very strongly acid; clear smooth boundary. [0 to 15 cm (6 inches) thick]
Bt1--41 to 53 cm (16 to 24 inches); yellowish brown (10YR 5/8) silty clay loam; moderate fine subangular blocky structure; firm; common roots; common prominent brown (10YR 4/3) clay films on faces of peds; common prominent light brownish gray (10YR 6/2) clay depletions on faces of peds, light gray (10YR 7/1) dry; few fine prominent light brownish gray (10YR 6/2) and brown (10YR 5/3) iron depletions in the matrix; many fine iron-manganese concretions throughout; very strongly acid; clear smooth boundary.
Bt2--53 to 69 cm (24 to 27 inches); yellowish brown (10YR 5/8 and 10YR 5/4) silty clay loam; moderate coarse subangular blocky structure parting to moderate fine and very fine angular blocky; firm; common roots; many prominent light brownish gray (10YR 6/2) clay depletions on faces of larger peds and many distant brown (10YR 4/3) clay films on faces of smaller angular peds; few fine prominent light gray (10YR 7/1) iron depletions in the matrix; many medium iron-manganese concretions throughout; many black (10YR 2/1) threadlike manganese coatings and spherical manganese masses; very strongly acid; clear smooth boundary
Bt3--69 to 81 cm (27 to 32 inches); yellowish brown (10YR 5/8 and 10YR 5/4) silty clay loam; moderate medium subangular blocky structure; very firm; common roots; many distinct brown (10YR 4/3) clay films on faces of peds; few fine prominent light gray (10YR 7/1) and light brownish gray (10YR 6/2) iron depletions in the matrix; many fine iron-manganese concretions throughout; common black (10YR 2/1) threadlike manganese coatings and spherical manganese masses; very strongly acid; gradual smooth boundary. [Combined thickness of the Bt horizon is 25 to 76 cm (10 to 30 inches).]
Btx1--81 to 91 cm (32 to 36 inches); mottled grayish brown (10YR 5/2), brown (10YR 5/3), and yellowish brown (10YR 5/8) silty clay loam; weak coarse subangular blocky structure; firm; common roots; common distinct brown (10YR 4/3) clay films on faces of peds; few fine distinct light gray (10YR 7/1) iron depletions in the matrix; many iron-manganese concretions throughout; brittle; very strongly acid; gradual smooth boundary.
Btx2--91 to 114 cm (36 to 45 inches); mottled grayish brown (10YR 5/2) brown (10YR 5/3) and yellowish brown (10YR 5/8) silty clay loam; weak coarse prismatic structure; extremely firm; few roots; few distinct brown (10YR 4/3) clay films on faces of peds; common fine and medium distinct light gray (10YR 7/1) iron depletions in the matrix; many fine iron-manganese concretions throughout; brittle; very strongly acid; gradual smooth boundary. [Combined thickness of the Btx horizon is 20 to 76 cm (8 to 30 inches).]
Bx--114 to 203 cm (45 to 80 inches); mottled grayish brown (10YR 5/2), pale brown (10YR 6/3), yellowish brown (10YR 5/8), and light gray (10YR 7/1) silt loam; weak medium prismatic structure; extremely firm; few very dark grayish brown (10YR 3/2) threadlike manganese coatings and spherical manganese masses; many fine iron-manganese concretions throughout; brittle; very strongly acid.
TYPE LOCATION: Gallatin County, Illinois, about 2 miles southwest of Omaha; 1,320 feet east of southwest corner of sec. 28, T. 7 S., R. 8 E.; USGS Norris City topographic quadrangle; lat. 37 degrees 52 minutes 43 seconds N. and long. 88 degrees 19 minutes 58 seconds W.; UTM Zone 16, 382795 easting and 4193237 northing, NAD 83.
RANGE IN CHARACTERISTICS:
Depth to fragic soil properties: 64 to 114 cm (25 to 45 inches)
Depth to the base of the argillic horizon: 89 to 165 cm (35 to 65 inches)
Particle-size control section: averages 27 and 35 percent clay
Series control section: less than 10 percent fine sand or coarser material throughout the profile
Ap horizon:
Hue: 10YR
Value: 4 or 5
Chroma: 2 or 3
Texture: silt loam, but includes silty clay loam in some eroded pedons
Reaction: very strongly acid to neutral
A horizon (in undisturbed areas):
Hue: 10YR
Value: 2 to 3
Chroma: 1 or 2
Texture: commonly silt loam; less commonly silty clay loam
Reaction: very strongly acid to neutral
E, BE, or B/E horizon, where present:
Hue: 10YR
Value: 5 or 6
Chroma: 3 or 4
Reaction: very strongly acid to slightly acid
Texture: silt loam; silty clay loam in some BE horizons
Reaction: very strongly acid to neutral
Bt horizon:
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 2 to 8
Texture: silty clay loam or silt loam
Reaction: very strongly acid or strongly acid
Btx or Bx horizon
Hue: 10YR
Value: 5 to 7
Chroma: 2 to 8
Texture: silty clay loam or silt loam
Clay content: 24 to 35 percent
Reaction: very strongly acid to moderately acid
C horizon, where present
Hue: 10YR
Value: 5 to 7
Chroma: 1 to 8
Texture: silt loam
Clay content: 20 to 27 percent
Reaction: very strongly acid to neutral
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: The Stoy soils are on ridgetops on loess covered Illinoian till plains and bedrock plateaus. Slope ranges from 0 to 10 percent. The soils are formed in loess. Mean annual precipitation ranges from 889 to 1143 mm (35 to 45 inches). Mean annual air temperature ranges from 12 to 14 degrees C (54 to 57 degrees F). Frost-free period is 180 to 200 days. Elevation is 104 to 311 meters (340 to 1,020 feet) above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Hosmer and
Weir soils. Hosmer soils are moderately well drained, have fragipan horizons, and are on nearby landscapes generally with steeper slope gradients. Weir soils are poorly drained and are dominated by chroma of 1 and 2 in the solum.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. Depth to the top of a perched seasonal high water table ranges from 31 to 61 cm (1 to 2 feet) in drained areas between January and May in normal years. Potential for surface runoff is low to high. Saturated hydraulic conductivity is moderately low. Permeability is slow.
USE AND VEGETATION: Most areas are cropland but some still remains in forest. Native vegetation is mixed hardwood forest.
DISTRIBUTION AND EXTENT: MLRAs 113, 114B, 115A, 115B, 120A, 120C and 122 in southern Illinois and southern Indiana. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Lawrence County, Illinois, 1952.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: from the surface to a depth of 41 cm (16 inches) (Ap, E1, E2, BE horizons).
Argillic horizon: from a depth of 41 to 114cm (16 to 45 inches) (Bt1, Bt2, Bt3, Btx1, Btx2 horizons).
Aquic conditions: redoximorphic features present in all horizons beneath the Ap horizon.
National Cooperative Soil Survey
U.S.A.