LOCATION KURTZ INEstablished Series
The Kurtz series consists of deep, well drained, soils on hills. They formed in residuum weathered from interbedded soft siltstone and shale bedrock. Slopes range from 20 to 60 percent. Mean annual precipitation is about 1067 mm (42 inches), and mean annual temperature is about 12 degrees C (53 degrees F).
TAXONOMIC CLASS: Fine-silty, mixed, semiactive, mesic Ultic Hapludalfs
TYPICAL PEDON: Kurtz silt loam on an east-facing convex slope of 37 percent in a hardwood-forested area at an elevation of about 210 meters (690 feet) above MSL. (Colors are for moist soil unless otherwise stated.)
Oi--0 to 3 cm (0 to 1 inch); roots and partially decomposed leaves. (0 to 5 cm or 0 to 2 inches thick)
A--3 to 8 cm (1 to 3 inches); grayish brown (10YR 5/2) silt loam, pale brown (10YR 6/3) dry; moderate medium and fine granular structure; friable; many fine and medium roots; 5 percent gravel (ironstone); extremely acid; abrupt smooth boundary. (5 to 13 cm or 2 to 5 inches thick)
E--8 to 18 cm (3 to 7 inches); light yellowish brown (2.5Y 6/4) silt loam; moderate medium and fine granular structure; friable; many fine and medium roots; 4 percent gravel (ironstone); extremely acid; clear smooth boundary. (0 to 15 cm or 0 to 6 inches thick)
BE--18 to 33 cm (7 to 13 inches); brownish yellow (10YR 6/6) silt loam; moderate medium and fine subangular blocky structure; friable; common medium and coarse roots; 2 percent gravel (ironstone); very strongly acid; clear wavy boundary. (0 to 15 cm or 0 to 6 inches thick)
Bt1--33 to 53 cm (13 to 21 inches); yellowish brown (10YR 5/6) silt loam; common fine faint strong brown (7.5YR 5/6) mottles; moderate medium subangular blocky structure; friable; common medium and coarse roots; many distinct light yellowish brown (10YR 6/4) silt coating the clay films on faces of peds; 2 percent gravel (ironstone); very strongly acid; clear wavy boundary.
Bt2--53 to 94 cm (21 to 37 inches); strong brown (7.5YR 5/6) and light yellowish brown (2.5Y 6/4) silty clay loam; common fine prominent greenish gray (5GY 6/1) and distinct yellowish red (5YR 4/6) mottles; moderate fine and medium subangular blocky structure; firm; common medium and coarse roots; many prominent light yellowish brown (2.5Y 6/4) clay films on faces of peds; 2 percent gravel and cobbles (ironstone); 10 percent parachanners; very strongly acid; gradual wavy boundary. (Combined thickness of the Bt horizons is 51 to 81 cm or 20 to 32 inches.)
CB--94 to 119 cm (37 to 47 inches); light olive brown (2.5Y 5/4) extremely parachannery silty clay loam; many medium prominent gray (5Y 6/1), greenish gray (5GY 6/1) and common fine distinct strong brown (7.5YR 5/6) mottles; weak medium and fine subangular blocky structure, and thick platy rock structure; firm; few medium and coarse roots; 5 percent gravel and cobbles (ironstone); 60 percent parachanners; very strongly acid; gradual wavy boundary. (15 to 36 cm or 6 to 14 inches thick)
Cr--119 to 152 cm (47 to 60 inches); olive (5Y 4/3) interbedded moderately cemented siltstone and shale bedrock; light olive gray (5Y 6/2) coatings between fragments; 5 percent gravel and cobbles (ironstone); strongly acid.
TYPE LOCATION: Jackson County, Indiana; about 1 1/2 miles southeast of Brownstown; 500 feet east and 2,000 feet south of the northwest corner of sec. 19, T. 5 N., R. 5 E.; USGS Vallonia, Indiana topographic quadrangle; lat. 38 degrees 51 minutes 42 seconds N. and long. 086 degrees 01 minutes 02 seconds W., NAD 27; UTM Zone 16, 585269 easting and 4301890 northing, NAD 83.
RANGE IN CHARACTERISTICS:
Depth to the base of the argillic horizon: 81 to 122 cm (32 to 48 inches)
Depth to a paralithic contact: 102 to 152 cm (40 to 60 inches)
Pararock fragments: weakly or moderately cemented siltstone or shale
Rock fragments: indurated ironstone
A horizon:
Hue: 10YR
Value: 3 to 5
Chroma: 2 or 3
Texture: is silt loam
Clay content:12 to 22 percent
Sand content: 2 to 8 percent
Reaction: extremely acid or very strongly acid.
Rock fragment content: 1 to 5 percent gravel
E horizon:
Hue: 10YR
Value: 5 or 6
Chroma: 3 or 4
Texture: silt loam
Clay content: 12 to 22 percent
Sand content: 2 to 8 percent
Reaction: extremely acid or very strongly acid
Rock fragment content: 1 to 5 percent gravel
BE or Bt horizon:
Hue: 7.5YR, 10YR, or 2.5Y
Value: 5 or 6
Chroma: 4 to 6
Texture: silt loam or silty clay loam, or their parachannery analogues
Clay content: 25 to 35 percent
Sand content: 2 to 8 percent
Reaction: extremely acid or very strongly acid.
Rock fragment content: 1 to 5 percent gravel and cobbles
Pararock fragment content: 0 to 30 percent parachanners
CB or BC horizon:
Hue: 10YR, 2.5Y, or 5Y
Value: 5 or 6
Chroma: 3 to 6
Texture: very parachannery or extremely parachannery analogues of silt loam or silty clay loam
Clay content: 25 to 32 percent
Sand content: 2 to 8 percent
Reaction: very strongly acid or strongly acid
Rock fragment content: 1 to 5 percent gravel and cobbles
Pararock fragment content: 35 to 70 percent parachanners
Cr horizon:
Hue: 2.5Y or 5Y
Value: 4 to 6
Chroma: 3 or 4
COMPETING SERIES: This is the Rosine series. The Rosine soils have the upper part of the solum formed in loess and average more than 35 percent clay in the lower part of the argillic horizon.
GEOGRAPHIC SETTING: The Kurtz soils are on moderately steep to very steep hills. Slopes range from 20 to 60 percent. Kurtz soils formed in residuum weathered from interbedded soft siltstone and shale bedrock. Mean annual precipitation ranges from 1016 to 1168 mm (40 to 46 inches), and the mean annual temperature ranges from 11 to 14 degrees C (52 to 57 degrees F). Frost free period in 170 to 200 days, and elevation ranges from 122 to 274 meters (400 to 900 feet).
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Coolville, Gnawbone, Rarden, and Stonehead soils. The moderately well drained Coolville, Rarden, and Stonehead soils are on less sloping shoulders and backslopes. The moderately deep, well drained Gnawbone soils are on similar backslope positions as the Kurtz.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers/s) in the solum. Permeability is moderate in the solum. The potential for surface water runoff is high.
USE AND VEGETATION: Most areas of Kurtz soils are in forest. Native vegetation consists of mixed hardwoods with oaks, hickory, beech, and tulip poplar the major species.
DISTRIBUTION AND EXTENT: Southern Indiana. The series is of moderate extent in MLRA 120C.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Jackson County, Indiana, 1985.
REMARKS: The mottles in the control section are not considered to be redoximorphic features. Base saturation of the typical pedon is borderline the Alfisol and Ultisol Order. A summary of base saturation data indicates that the classification of this series should be in the ultic subgroup of Alfisols. Particle-size data shows that this series borders the fine-silty and fine family, and possibly having illitic mineralogy. The CEC activity class assigned is semiactive, but lab data indicates the range to be both in active and semiactive.
Representative Component and horizon data is in DMU# 124507.
Diagnostic horizons and features recognized in this pedon are: 1) ochric epipedon - the zone from approximately 3 to 33 cm (1 to 13 inches) (A, E, BE horizons); 2) argillic horizon - the zone from approximately 33 to 94 cm (13 to 37 inches) (Bt1 and Bt2 horizons); and 3) paralithic contact at 119 cm (47 inches).
ADDITIONAL DATA: Laboratory data from Purdue Soils Laboratory number S78IN71-6-(1-7), File No. JN8061 (typical pedon). Lab data available for sample no. S90IN-143-1 from the NSSL in Lincoln, NE.