LOCATION GNAWBONE INEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, semiactive, mesic Typic Hapludults
TYPICAL PEDON: Gnawbone silt loam on a west-facing, convex slope of 22 percent in a forested area at an elevation of about 219 meters (720 feet) above MSL. (Colors are for a moist soil unless stated otherwise)
Oi--0 to 3 cm (0 to 1 inches); partially decomposed leaves from mixed deciduous trees.
A--3 to 18 cm (1 to 7 inches); light yellowish brown (10YR 6/4) silt loam, very pale brown (10YR 7/4) dry; weak medium subangular blocky structure parting to moderate medium granular; friable; many very fine to medium, and few coarse roots; 3 percent gravel (ironstone); extremely acid; clear wavy boundary. (10 to 20 cm or 4 to 8 inches thick)
Bt1--18 to 30 cm (7 to 12 inches); yellowish brown (10YR 5/6) silt loam; weak medium subangular blocky structure; friable; many medium, common fine and very fine, and few coarse roots between peds; few distinct strong brown (7.5YR 5/6) clay films on faces of peds; 3 percent gravel (ironstone); 10 percent parachanners; extremely acid; clear wavy boundary.
Bt2--30 to 43 cm (12 to 17 inches); dark yellowish brown (10YR 4/6) parachannery silty clay loam; moderate medium subangular blocky structure; friable; common very fine to medium, and few coarse roots between peds; common distinct strong brown (7.5YR 5/6) clay films on faces of peds; 10 percent gravel (ironstone); 15 percent parachanners; very strongly acid; clear wavy boundary.
Bt3--43 to 69 cm (17 to 27 inches); dark yellowish brown (10YR 4/6) parachannery silty clay loam; moderate medium subangular blocky structure; friable; common fine and medium, and few coarse roots between peds; many distinct strong brown (7.5YR 5/6) clay films on faces of peds; 3 percent percent gravel (ironstone); 20 percent parachanners; very strongly acid; clear wavy boundary.
Bt4--69 to 89 cm (27 to 35 inches); yellowish brown (10YR 5/4) very parachannery silt loam; moderate fine subangular blocky structure; friable; common fine and medium roots between peds; few distinct strong brown (7.5YR 5/6) clay films on faces of peds; 3 percent percent gravel (ironstone); 35 percent parachanners; very strongly acid; gradual wavy boundary. (Combined thickness of the Bt horizon is 36 to 76 cm or 14 to 30 inches)
CB--89 to 99 cm (35 to 39 inches); yellowish brown (10YR 5/4) extremely parachannery silt loam; weak fine subangular blocky structure; friable; 3 percent percent gravel (ironstone); 60 percent parachanners; very strongly acid; gradual wavy boundary. (8 to 20 cm or 3 to 8 inches thick)
Cr--99 to 152 cm (39 to 60 inches); light olive brown (2.5Y 5/4) fractured, moderately cemented siltstone bedrock.
TYPE LOCATION: Scott County, Indiana; 600 feet south and 450 feet west of the northeast corner of sec. 28, T. 2 N., R. 6 E., USGS Henryville, Indiana topographic quadrangle; lat. 38 degrees 35 minutes 13 seconds N. and long. 085 degrees 51 minutes 01 second W., NAD 27; UTM Zone 16, 600136 easting and 4271573 northing, NAD 83.
RANGE IN CHARACTERISTICS:
Depth to the base of the argillic horizon: 46 to 91 cm (18 to 36 inches)
Depth to a paralithic contact: 51 to 102 cm (20 to 40 inches)
Pararock fragments are weakly or moderately cemented siltstone, rock fragments are primarily indurated ironstone
A or Ap horizon, where present:
Hue: 10YR
Value: 3 to 6
Chroma: 2 to 4
Texture: silt loam
Clay content: 10 to 20 percent
Sand content: 5 to 15 percent sand
Reaction: extremely acid or very strongly acid, and ranges to neutral in limed areas
Rock fragment content: ranges from 1 to 5 percent gravel
Bt or BE horizon, where present:
Hue: 7.5YR or 10YR
Value: 4 to 6
Chroma: 4 to 6
Texture: silt loam or silty clay loam and their parachannery and very parachannery analogues
Clay content: 24 to 34 percent
Sand content: 5 to 15 percent sand
Pararock fragment content: 0 to 35 percent parachanners
Rock fragment content: 1 to 12 percent gravel and cobbles
Reaction: extremely acid or very strongly acid
CB or BC horizon:
Hue: 7.5YR, 10YR or 2.5Y
Value: 5 or 6
Chroma: 4 to 8
Texture: parachannery to extremely parachannery silt loam or silty clay loam
Clay content: 15 to 32 percent
Sand content: 5 to 15 percent
Pararock fragment content: 30 to 70 percent parachanners
Rock fragment content: from 1 to 12 percent gravel and cobbles
Reaction: extremely acid or very strongly acid
Cr horizon:
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 3 to 6
COMPETING SERIES: These are the Cabool , Chillum, Fletcher, Jessietown, Matapeake, Nassawango, Wernock, and Whitley soils. Cabool and Jessietown soils are moderately deep to a lithic contact. Chillum, Metapeake, and Nassawango soils do not have bedrock within a depth of 152 cm (60 inches) and formed in marine or coastal sediments. Fletcher soils are deep or very deep to a lithic contact. Whitley soils do not have bedrock within a depth of 152 cm (60 inches) and formed in materials derived from bedrock. Wernock soils compete very closely, but typically have a hue of 5YR, and typically average more than 15 percent sand in the lower part of the series control section.
GEOGRAPHIC SETTING: Gnawbone soils are on moderately sloping to very steep shoulders and backslopes of hills. Slopes range from 6 to 60 percent. They formed in residuum from siltstone. The mean annual temperature ranges from 11 to 14 degrees C (51 to 57 degrees F), the mean annual precipitation ranges from 102 to 114 cm (40 to 45 inches), frost free period ranges from 170 to 200 days, and elevation ranges from 183 to 305 meters (600 to 1000 feet) above mean sea level.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Brownstown, Gilwood, Spickert, Wellrock and Wrays soils on hills, and the deep, moderately well drained Beanblossom soils on flood plains. The well drained Brownstown and Gilwood soils are on higher lying shoulders and backslopes, and have a lithic contact. The moderately well drained, deep and very deep Spickert, and well drained, deep Wrays soils typically are on higher lying summits, shoulders and backslopes. The well drained, deep Wellrock soils are on shoulders and backslopes.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for surface water runoff is medium or high. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers/s) in the solum. Permeability is moderate in the solum.
USE AND VEGETATION: Most areas are in mixed hardwood forest, the native vegetation. A few areas are used for hay and pasture.
DISTRIBUTION AND EXTENT: South-central Indiana. This series is of small extent, in MLRA 120C.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Scott County, Indiana, 1995. The name is a small community in Brown County, Indiana.
REMARKS: Gnawbone soils were previously correlated as Gilpin soils underlain with a paralithic contact. Geological Survey Occasional Paper 43 from the Indiana Department of Natural Resources describes the bedrock in Indiana (Spickert Knob Formation, Borden Group).
Diagnostic horizons recognized in this pedon are: 1) Ochric epipedon: the zone from approximately 3 to 18 cm (1 to 7 inches), (A horizon); 2) Argillic horizon: the zone from approximately 18 to 89 cm (7 to 35 inches), (Bt1, Bt2, Bt3, Bt4 horizons); and 3) Paralithic contact: the zone where soil meets soft bedrock at 99 cm (39 inches).
ADDITIONAL DATA: Data for this pedon, S88IN-143-005 is available at the National Soil Survey Laboratory, Lincoln, NE.