LOCATION ASHDALE IL+IA WIEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Typic Argiudolls
TYPICAL PEDON: Ashdale silt loam in a cultivated field at an elevation of about 288 meters above sea level (945 feet). (Colors are for moist soil unless otherwise stated.)
Ap--0 to 18 cm (0 to 7 inches); black (10YR 2/1) silt loam; moderate fine and medium granular structure; friable; neutral; abrupt smooth boundary.
A1--18 to 25 cm (7 to 10 inches); black (10YR 2/1) silt loam; moderate medium and coarse granular structure; friable; neutral; clear smooth boundary.
A2--25 to 38 cm (10 to 15 inches); very dark grayish brown (10YR 3/2) silt loam; moderate fine granular structure; friable; few distinct black (10YR 2/1) organic coatings on faces of peds; neutral; clear smooth boundary. [Combined thickness of the A horizon is 30 to 53 cm (12 to 21 inches) thick]
Bt1--38 to 58 cm (15 to 23 inches); brown (10YR 4/3) silty clay loam; moderate medium subangular blocky structure; firm; few faint brown (10YR 4/3) clay films on faces of peds; moderately acid; clear smooth boundary.
Bt2--58 to 84 cm (23 to 33 inches); dark yellowish brown (10YR 4/4) silty clay loam; moderate medium and coarse subangular blocky structure; firm; common faint brown (10YR 4/3) clay films on faces of peds; moderately acid; clear smooth boundary.
Bt3--84 to 109 cm (33 to 43 inches); dark yellowish brown (10YR 4/4) silty clay loam; moderate medium and coarse subangular blocky structure; firm; many faint brown (10YR 4/3) clay films on faces of peds; moderately acid; clear smooth boundary. [Combined thickness of the Bt horizon is 53 to 86 cm (21 to 34 inches)
2Bt4--109 to 130 cm (43 to 51 inches); reddish brown (5YR 4/4) silty clay; weak coarse angular blocky structure; very firm; many faint dark reddish brown (5YR 3/4) clay films on faces of peds; slightly acid; abrupt smooth boundary. [5 to more than 61cm (2 to more than 24 inches) thick]
2R--130 cm (51 inches); brownish yellow (10YR 6/6) limestone bedrock.
TYPE LOCATION: Stephenson County, Illinois; about 2 1/2 miles east of Cedarville; 2,116 feet north and 45 feet west of the southeast corner of sec. 4, T. 27 N., R. 8 E.; USGS Freeport East topographic quadrangle; lat. 42 degrees 21 minutes 56 seconds N., and long. 89 degrees 34 minutes 27 seconds W., NAD 83.
RANGE IN CHARACTERISTICS: The solum typically is 114 to 140 cm (45 to 55 inches) thick but ranges from 102 to 152 cm (40 to 60 inches). The loess is 91 to 127 cm (36 to 50 inches) thick and the residuum commonly is 5 to 30 cm (2 to 12 inches) thick, but in some pedons it ranges to more than 61 cm (24 inches). In some pedons outwash material that contains a component of sand is between the loess and the residuum. It is below 102 cm (40 inches) but still within the solum. The depth to limestone bedrock ranges from 102 to 153 cm (40 to 60 inches) and is considered to be a lithic contact. It is deeper in some pedons that have thick residuum. Reaction of the most acid part of the solum is moderately acid or strongly acid. The particle-size control section (weighted average) contains 27 to 35 percent clay.
The A or Ap horizon has hue of 10YR, value of 2 or 3, and chroma of 1 to 3.
The Bt horizon has hue of 10YR, value of 4 or 5, and chroma of 3 to 6. It is typically silty clay loam, but in some pedons the lower part of this horizon is silt loam.
The 2Bt horizon has hue of 5YR or 2.5YR, or less commonly 7.5YR or 10YR, value of 3 to 5, and chroma of 3 to 5. It has 55 to 75 percent clay. In some pedons it contains a component of chert fragments. In some pedons the upper few inches of bedrock is partially disintegrated.
COMPETING SERIES: These are the Broadwell, Dinsdale, Douglas, Elkhart, Elmont, Healing, Lycurgus, Malcolm, Meadowbank, Mendota, Mickle, Ogle, Osco, Parkway, Plano, Proctor, Richwood, Ripon, Sibley, Sidell, Tama, Tecumseh, Toddville, Wakenda, and Waupecan series. All of the series except Elmont and Ripon do not have clay or silty clay 2Bt horizons nor sola terminated by bedrock. Elmont series have less than 55 percent clay in the lower sola and have a paralithic contact with silty shale at depths of 102 to 152 cm (40 to 60 inches). Ripon series have thinner sola and are underlain by limestone bedrock at depths of 51 to 102 cm (20 to 40 inches).
GEOGRAPHIC SETTING: Ashdale soils are on nearly level and gently sloping ridgetops and strongly sloping to moderately steep convex slopes in dissected upland areas. Slope gradients commonly are 3 to 12 percent and range from 0 to 20 percent. These soils formed in 91 to 127 cm (36 to 50 inches) of loess and in a thin layer of residuum weathered from limestone bedrock. Summers are hot and winters are cold. Mean annual air temperature ranges from 7 to 12 degrees C (45 to 53 degrees F). Mean annual precipitation ranges from 71 to 102 cm (28 to 40 inches). Frost-free period ranges from 130 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dodgeville, Nasset, Palsgrove, and Tama soils. Dodgeville soils are in a contrasting particle size family and are underlain by limestone bedrock at depths of 51 to 102 cm (20 to 40 inches). Dodgeville soils are on steeper side slopes in areas where Ashdale soils are on ridgetops. Tama soils are on ridgetops in areas where Ashdale soils are on side slopes,. Ashdale soils are in a biosequence with Nasset soils (Mollic Hapludalfs) and Palsgrove soils (Typic Hapludalfs).
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained..
Saturated hydraulic conductivity is 4.23 to 14.11 micrometers per second (moderate permeability) in the loess and 0.42 to 1.41 micrometers per second (slow permeability) in the clayey residuum. Surface runoff potential is medium to high as related to slope
USE AND VEGETATION: Most of the lesser sloping areas are cropped to corn, hay, legume-grass pasture, or small grains. Steeper slopes are mainly used for pasture. Native vegetation is probably tall prairie grasses, chiefly bluestem.
DISTRIBUTION AND EXTENT: Northwestern Illinois, southwestern Wisconsin, and northeastern Iowa in unglaciated areas and glaciated areas where drift has not contributed significantly to the solum. LRRs K and M, MLRAs 95B, 104, 105, and 108. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Lafayette County, Wisconsin, 1964.
REMARKS: The Ashdale series covers part of the former Dodgeville, deep phase and that part of Tama which was developed in more than 107 cm (42 inches) of loess but had B horizons continuing into residuum weathered from limestone.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from a depth of 0 to 38 cm (0 to 15 inches) (Ap, A1, and A2 horizons);
Argillic horizon - from a depth of 38 to 130 cm (15 inches to 51 inches) (Bt1, Bt2, Bt3 and 2Bt4 horizons).
Lithic contact--a depth of 130 cm (15 inches)
Udic moisture regime; Mesic temperature regime.