LOCATION BLOCHER IN

Established Series
Rev. GRS-BGN
11/2021

BLOCHER SERIES

The Blocher series consists of very deep, moderately well drained soils on till plains. They formed in 41 to 91 cm (16 to 36 inches) of loess and loamy materials, and the underlying paleosol in till. Slope ranges from 6 to 18 percent. Mean annual precipitation is about 1092 mm (43 inches), and mean annual air temperature is about 12 degrees C (54 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, active, mesic Oxyaquic Hapludalfs

TYPICAL PEDON: Blocher silt loam, on a 9 percent slope in a hayfield at an elevation of about 174 meters (570 feet) above MSL. (Colors are for moist soil unless otherwise stated.)

Ap--0 to 15 cm (6 inches); brown (10YR 4/3) silt loam, pale brown (10YR 6/3) dry; moderate fine and medium granular structure; friable; many very fine and fine roots; moderately acid; abrupt smooth boundary.[8 to 25 cm (3 to 10 inches) thick]

Bt1--15 to 43 cm (6 to 17 inches); strong brown (7.5YR 5/6) silty clay loam; moderate fine and medium subangular blocky structure; friable; common very fine and fine roots; many distinct brown (7.5YR 5/4) clay films on faces of peds; common distinct dark yellowish brown (10YR 4/4) organic coatings in root channels; few distinct yellowish brown (10YR 5/4) silt coatings on faces of peds; very strongly acid; clear wavy boundary. [15 to 38 cm (6 to 15 inches) thick]

2Bt2--43 to 61 cm (17 to 24 inches); strong brown (7.5YR 5/6) clay loam; strong fine and medium subangular blocky structure; firm; common very fine roots; common prominent dark yellowish brown (10YR 4/4) and very few prominent grayish brown (10YR 5/2) clay films on faces of peds; many distinct pale brown (10YR 6/3) silt coatings on faces of peds; 1 percent gravel; very strongly acid; gradual wavy boundary.

2Bt3--61 to 84 cm (24 to 33 inches); yellowish brown (10YR 5/6) clay loam; strong fine and medium angular blocky structure; very firm; few very fine roots between peds; many distinct strong brown (7.5YR 5/6) and common prominent grayish brown (10YR 5/2) and few distinct brown (7.5YR 4/4) clay films on faces of peds; common medium prominent light brownish gray (10YR 6/2) iron depletions in the matrix; 8 percent gravel; very strongly acid; clear wavy boundary.

2Bt4--84 to 112 cm (33 to 44 inches); strong brown (7.5YR 5/6) clay; strong fine and medium angular blocky structure; very firm; few very fine roots between peds; many distinct strong brown (7.5YR 4/6) and few prominent grayish brown (10YR 5/2) clay films on faces of peds; few fine prominent light brownish gray (10YR 6/2) iron depletions in the matrix; 10 percent gravel; strongly acid; gradual wavy boundary.

2Bt5--112 to 135 cm (44 to 53 inches); yellowish brown (10YR 5/6) clay loam; moderate fine and medium subangular blocky structure; very firm; many distinct dark yellowish brown (10YR 4/4) and few distinct grayish brown (10YR 5/2) clay films on faces of peds; common medium prominent black irregular masses of manganese lining pores; 3 percent gravel; slightly acid; gradual wavy boundary.

2Bt6--135 to 157 cm (53 to 62 inches); yellowish brown (10YR 5/6) clay loam; moderate fine and medium subangular blocky structure; firm; common distinct dark yellowish brown (10YR 4/4) clay films on faces of peds; few medium prominent black irregular masses of manganese lining pores; 3 percent gravel; neutral; gradual wavy boundary. [Combined thickness of the 2Bt horizon is 91 to 152 cm (36 to 60 inches).]

2BCt--157 to 193 cm (62 to 76 inches); yellowish brown (10YR 5/6) clay loam; weak fine and medium subangular blocky structure; firm; very few distinct dark yellowish brown (10YR 4/4) clay films on faces of peds; few medium prominent black irregular masses of manganese lining pores; 3 percent gravel; neutral; gradual wavy boundary. [20 to 41 cm (8 to 16 inches) thick]

2C--193 to 203 cm (76 to 80 inches); yellowish brown (10YR 5/4) loam (65 percent) with pockets of clay loam (35 percent); common coarse distinct strong brown (7.5YR 5/6) mottles; massive; friable; common medium and coarse prominent black irregular masses of manganese lining pores; 3 percent gravel; slightly alkaline.

TYPE LOCATION: Scott County, Indiana; 390 feet east and 720 feet north of the southwest corner of sec. 3, T. 4 N., R. 7 E.; USGS Deputy, Ind. topographic quadrangle; lat. 38 degrees 48 minutes 38.324 seconds N. and long. 085 degrees 44 minutes 18.067 seconds W.; UTM Zone 16, 609543.029 easting and 4296512.536 northing, NAD 83.

RANGE IN CHARACTERISTICS:
Thickness of the loess and loamy material: 41 to 91 cm (16 to 36 inches)
Depth to the base of the argillic horizon: 127 to 203 cm (50 to 80 inches)
Particle-size control section: averages 22 to 34 percent clay and 5 to 15 percent sand.
Mean annual soil temperature: 12 to 14 degrees C (54 to 58 degrees F)

Ap horizon:
Hue: 10YR
Value: 4 or 5
Chroma: 3 to 6
Texture: silt loam or silty clay loam (severely eroded pedons)
Clay content: 12 to 32 percent
Sand content: 3 to 25 percent
Reaction: very strongly acid to neutral

A horizon (2 to 5 inches thick), where present:
Hue: 10YR
Value: 3 or 4
Chroma: 2 or 3
Texture: silt loam
Clay content: 12 to 20 percent
Sand content: 3 to 25 percent
Reaction: strongly acid or very strongly

Bt horizon:
Hue: of 10YR or 7.5YR
Value: 4 or 5
Chroma: of 4 to 6
Texture: silt loam or silty clay loam, and ranges to loam in the lower part
Clay content: 20 to 30 percent
Sand content: 5 to 25 percent
Reaction: strongly acid or very strongly acid, and the upper part ranges to slightly acid in limed areas

2Bt horizon:
Hue: 10YR or 7.5YR
Value: 5
Chroma: 4 to 8
Texture: clay loam or clay
Clay content: 35 to 45 percent
Sand content: 25 to 35 percent
Rock fragment content: 3 to 10 percent, mainly gravel and includes cobbles
Reaction: very strongly acid or strongly acid in the upper part and ranges to neutral in the lower part

2BCt horizon:
Hue: 10YR or 7.5YR
Value: 5
Chroma: 4 to 8
Texture: clay loam or clay
Clay content: 30 to 40 percent
Sand content: 25 to 38 percent
Rock fragment content: 3 to 10 percent, mainly gravel and includes cobbles
Reaction: moderately acid to slightly alkaline

2C horizon:
Hue: 10YR
Value: 5 or 6
Chroma: 3 or 4
Texture: loam or clay loam
Clay content: 16 to 28 percent
Sand content: 25 to 45 percent
Rock fragment content: 3 to 10 percent, mainly gravel and includes cobbles
Reaction: slightly alkaline or moderately alkaline

COMPETING SERIES: These are the Ashburn, Deuchars, Gallipolis, Jeneva, Percell, Stonehead, Tarhollow , and Westgate series. Ashburn soils have a lithic contact in the series control section. Deuchars and Stonehead, soils have a paralithic contact in the series control section. Gallipolis and Tarhollow soils do not have carbonates in the series control section. Jeneva and Percell soils average less than 25 percent sand in all subhorizons above a depth of 102 cm (40 inches). Westgate soils do not have rock fragments of igneous lithology.

GEOGRAPHIC SETTING: Blocher soils are on shoulders and backslopes of till plains. Slope ranges from 6 to 18 percent. They formed in 41 to 91 cm (16 to 36 inches) of loess and loamy materials, and the underlying paleosol in till of the Illinoian stage. Mean annual precipitation ranges from 1016 to 1143 mm (40 to 45 inches. Mean annual air temperature ranges from 11 to 13 degrees C (52 to 56 degrees F). Frost-free period is 170 to 200 days. Elevation is 167 to 259 meters (550 to 850 feet) above mean sea level.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bonnell, Cincinnati, Hickory, Jennings, Nabb and Weddel series. The Bonnell and Hickory soils do not have redoximorphic depletions above a depth of 102 cm (40 inches), and are on lower lying, steeper backslopes. Cincinnati, Jennings and Nabb soils have a fragipan in the series control section. The Weddel soils have a horizon with fragic soil properties (2Btx) in the series control section. Cincinnati, Jennings and Weddel soils are on similar positions on the landform, and are often part of a complex map unit that includes Blocher soils. Nabb soils are on higher lying shoulders and summits.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained. The depth to the top of a perched seasonal high water table ranges from 61 to 91 cm (2 to 3 feet) between December and April in normal years. The potential for surface water runoff is medium or high. Saturated hydraulic conductivity is moderately high or high in the upper part of the solum and moderately low or moderately high in the lower part. Permeability is moderate in the upper part of the solum and slow within the lower part.

USE AND VEGETATION: These soils are commonly used to grow corn and soybeans, hay or pasture. A few areas are in woodland. Native vegetation is mixed hardwood forest.

DISTRIBUTION AND EXTENT: MLRA 114A in southeastern Indiana. This series is of small extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: AMHERST, MASSACHUSETTS

SERIES ESTABLISHED: Scott County, Indiana, 1995

REMARKS: This series crosses both above and below the 15 percent 0.1 to 75 mm fraction size average in the particle-size control section. Additional data indicates this series is dominantly in the fine-silty rather than fine-loamy particle-size class and is revised to the fine-silty class as of 5/2000. The typical pedon averages 13.8 percent in the 0.1 to 75 mm fraction size. Lab data on two other phases average 21 and 23 percent in the 0.1 to 75 mm fraction size.

Hard bedrock substratum, soft bedrock, severely eroded and gullied phases are recognized.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: the zone from 0 to 15 cm (6 inches) (Ap horizon).
Argillic horizon: the zone from 15 to 157 cm (6 to 62 inches) (Bt, 2Bt horizons).
Redoximorphic features: at 43 to 135 cm (17 to 53 inches); clay films with a chroma of 2 or less are iron depleted redoximorphic features.

Representative component and horizon data for the Blocher Series is in the following data mapunits: DMU ID 124488 for the typical pedon; DMU ID 124480 for the soft bedrock substratum; and DMU ID 124520 for the hard bedrock substratum.

ADDITIONAL DATA: Data on the typical pedon S92IN143-001 is at the NSSC, Lincoln, NE.

National Cooperative Soil Survey
U.S.A.