LOCATION AVONBURG IN+KY OHEstablished Series
The Avonburg series consists of very deep, somewhat poorly drained soils that formed in loess and the underlying paleosol in till. They are moderately deep to a horizon with fragic soil properties. Avonburg soils are on summits of loess-covered till plains. Slopes range from 0 to 6 percent. Mean annual precipitation is about 1092 mm (43 inches) and mean annual temperature is about 12 degrees C (54 degrees F).
TAXONOMIC CLASS: Fine-silty, mixed, active, mesic Aeric Fragic Glossaqualfs
TYPICAL PEDON: Avonburg silt loam on a 1 percent slope in a cultivated field at an elevation of about 186 meters (610 feet) above MSL. (Colors are for moist soil unless stated otherwise.)
Ap--0 to 28 cm (0 to 11 inches); yellowish brown (10YR 5/4) silt loam, very pale brown (10YR 7/3) dry; weak medium granular structure; friable; common very fine roots; common fine rounded black (10YR 2/1) iron and manganese concretions throughout; very strongly acid; abrupt smooth boundary. (15 to 30 cm or 6 to 12 inches thick)
BE--28 to 53 cm (11 to 21 inches); brownish yellow (10YR 6/6) silt loam; weak medium subangular blocky structure; friable; few very fine roots; few fine rounded black (10YR 2/1) iron and manganese concretions throughout; many medium prominent light gray (10YR 7/2) iron depletions in the matrix; very strongly acid; clear wavy boundary. (18 to 33 cm or 7 to 13 inches thick)
Btg--53 to 94 cm (21 to 37 inches); light brownish gray (10YR 6/2) silty clay loam; moderate medium prismatic structure parting to moderate coarse subangular blocky; firm; few very fine roots; common distinct gray (10YR 6/1) clay films on faces of peds; common fine prominent strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; few fine rounded black (10YR 2/1) iron and manganese concretions throughout; many faint light gray (10YR 7/2) clay depletions on faces of peds; tongues 5 to 15 cm (2 to 6 inches) wide filled with light gray (10YR 7/2) silt loam, about 10 percent by volume; very strongly acid; gradual wavy boundary. (36 to 56 cm or 14 to 22 inches thick)
2Btgx/Eg--94 to 132 cm (37 to 52 inches); 50 percent light brownish gray (10YR 6/2) silt loam (Btgx); moderate coarse and very coarse prismatic structure parting to moderate coarse subangular blocky; very firm; brittle; common prominent gray (10YR 6/1) clay films on vertical faces of peds; many coarse prominent strong brown (7.5YR 5/6) masses of iron accumulation in the matrix; common faint light gray (10YR 7/2) clay depletions on vertical faces of peds; 50 percent light gray (10YR 7/2) silt loam (Eg) as tongues 5 to15 cm (2 to 6 inches) wide at the top that taper to 3 to 5 cm (1 to 2 inches) at the bottom, and have a concentration of illuviated grayish brown (10YR 5/2) silty clay loam in the lower part; weak medium and coarse subangular blocky structure; friable; few very fine roots; few fine rounded black (10YR 2/1) iron and manganese concretions throughout; 21 percent sand; 1 percent gravel; extremely acid; gradual wavy boundary. (25 to 51 cm or 10 to 20 inches thick)
2Btx--132 to 211 cm (52 to 83 inches); yellowish brown (10YR 5/6) silt loam; moderate very coarse prismatic structure parting to weak coarse subangular blocky; very firm; common prominent gray (10YR 6/1) clay films on faces of peds and in pores; few fine rounded black (10YR 2/1) iron and manganese concretions throughout; common coarse prominent light brownish gray (10YR 6/2) iron depletions in the matrix; 25 percent light gray (10YR 7/2) friable silt loam between peds; 24 percent sand; 1 percent gravel; 75 percent brittle; extremely acid; diffused wavy boundary.
3Btb--211 to 229 cm (83 to 90 inches); strong brown (7.5YR 5/8) clay loam; moderate coarse subangular blocky structure; firm; many prominent gray (10YR 6/1) clay films on faces of peds; few fine irregular black (10YR 2/1) iron and manganese concretions throughout; many medium prominent light gray (10YR 7/1) iron depletions in the matrix; 4 percent gravel; strongly acid.
TYPE LOCATION: Scott County, Indiana; 490 feet west and 685 feet south of the center of Sec. 21, T. 4 N., R. 7 E. USGS Crothersville, Indiana topographic quadrangle; lat. 38 degrees 46 minutes 14 seconds N. and long. 085 degrees 45 minutes 02 seconds W., NAD 27. (UTM Zone 16, 608544 easting and 4292062 northing, NAD 83).
RANGE IN CHARACTERISTICS:
Thickness of the loess: 152 to 229 cm (60 to 90 inches)
Depth to the base of the argillic horizon: more than 203 cm (80 inches)
Depth to the top of the horizon with fragic soil properties: 51 to 102 cm (20 to 40 inches).
Particle-size control section: averages 24 to 30 percent clay and 10 to 14 percent fine and coarser sand
Ap horizon:
Hue: 10YR
Value: 4 or 5
Chroma: 2 to 4
Texture: silt loam
Clay content: 10 to 18 percent
Sand content: 15 to 25 percent
Reaction: very strongly acid to neutral
A horizon (2 to 4 inches):
Hue: 10YR
Value: 3 or 4
Chroma: 1 or 2
Texture: silt loam
Clay content: 10 to 18 percent
Sand content: 15 to 25 percent
Reaction: very strongly acid or strongly acid
BE or EB horizon:
Hue: 10YR
Value: 5 or 6
Chroma: 2 to 6
Texture: silt loam.
Clay content: 12 to 20 percent
Sand content: 15 to 20 percent
Reaction: very strongly acid or strongly acid, and ranges to slightly acid in limed areas
Bt or Btg horizon:
Hue: 10YR
Value: 5 or 6
Chroma: 1 to 6, where the chroma is 3 or more, 50 percent or more of the faces of peds have chroma of 1 or 2
Texture: silt loam or silty clay loam
Clay content: 24 to 30 percent
Sand content: 8 to 20 percent
Reaction: extremely acid or very strongly acid
2Btgx/Eg or 2Btx/Eg horizon:
Btgx or Btx part:
Hue: 10YR
Value: 5 or 6
Chroma: 1 to 6.
Texture: commonly silt loam, and less commonly silty clay loam.
Clay content: 22 to 28 percent
Eg part:
Hue: 10YR
Value: 5 or 6
Chroma: 1 or 2
Texture: silt loam
Clay content: 22 to 26 percent
For both parts:
Sand content: 14 to 25 percent
Rock fragment content: 1 or 2 percent gravel (3 to 10 mm or 1/8-3/8 inches)
Brittle material content: 40 to 60 percent
Reaction: extremely acid to strongly acid.
2Btgx or 2Btx horizon:
Hue: 10YR
Value: 5 or 6
Chroma: 1 to 6
Texture: silt loam
Clay content: 20 to 26 percent
Sand content: 20 to 30 percent
Rock fragment content: 1 or 2 percent gravel (3 to 10 mm (1/8-3/8 inches))
Brittle material content: 60 to 80 percent
Reaction: extremely acid to strongly acid.
3Btb horizon:
Hue: 7.5YR or 10YR
Value: 5 or 6
Chroma: 2 to 8
Texture: clay loam
Clay content: 27 to 40 percent
Sand content: 25 to 35 percent
Rock fragment content: 2 to 10 percent, mainly gravel and includes cobbles and stones
Reaction: strongly acid to neutral.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Avonburg soils are on summits of loess-covered till plains. Slopes range from 0 to 6 percent. They formed in 152 to 229 cm (60 to 90 inches) of loess and the underlying paleosol in Illinoian till. The upper 51 to 102 cm (20 to 40 inches) of loess averages about 15 percent sand, and the lower loess averages about 24 percent. This lower loess has been called "gritty loess". The mean annual air temperature ranges from 11 to 14 degrees C (51 to 57 degrees F), the mean annual precipitation ranges from 889 to 1143 mm (35 to 45 inches), frost free period is 160 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 Bonnell, Cincinnati, Clermont, Cobbsfork, Hickory, Nabb and Rossmoyne soils. The well drained Bonnell, Cincinnati, and Hickory soils are on more sloping areas. The poorly drained Clermont and Cobbsfork soils are on broad flats. The moderately well drained Nabb and Rossmoyne soils are on similar landform positions.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat poorly drained. The potential for surface water runoff is medium. Saturated hydraulic conductivity is moderately high or high (4.23 to 14.11 micrometers/s) in the upper part of the solum and low to moderately high (0.07 to 1.41 micrometers/s) in the lower part. Permeability is moderate in the upper part of the solum and slow or very slow in the lower part. In undisturbed areas, in normal years, depth to an intermittent perched high water table is at a depth of 0.1 to 0.5 meters (0.5 to 1.5 feet). In drained areas, depth to the water table is 0.1 to 0.6 meters (0.5 to 2 feet).
USE AND VEGETATION: Most areas are being used to grow corn and soybeans. A few areas are used for growing small grain, mainly wheat, and for hay and pasture. Also a few areas are in woodland. Native vegetation is mixed hardwood forest.
DISTRIBUTION AND EXTENT: Mainly in MLRA 114A. It is of large extent in southeastern Indiana, and of small extent in southwestern Ohio and north-central Kentucky.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Switzerland County, Indiana, 1930.
REMARKS: Avonburg soils have previously been considered to be formed in 51 to 122 cm (20 to 48 inches) of loess and the underlying loam or clay loam till. Recent investigations and descriptions show a paleosol formed in till begins between a depth of 152 to 229 cm (60 and 90 inches). In 1995, the Type Location was moved to Scott County to more typically represent the Avonburg series.
An undrained phase is recognized.
Soil Survey Investigations Report No. 41 gives information on the origin of the gritty loess in the Avonburg and geographically associated soils.
Diagonostic horizons and features recognized in this pedon are:
1) Ochric epipedon: 0 to 28 cm (11 inches) Ap horizon
2) Argillic horizon: 53 to 203 cm (21 to 80 inches) - Btg, 2Btgx/Eg, and 2Btx horizons
3) Fragic soil properties: 94 to 211 cm (37 to 83 inches) - 2Btgx/Eg and 2Btx horizons
4) Glossic horizon: 94 to 132 cm (37 to 52 inches) - 2Btgx/Eg horizon
5) Redoximorphic features: from 28 to 203 cm (11 to 80 inches)
Representative component and horizon data for the Avonburg Series is in the following data mapunit: DMU ID 124474.
ADDITIONAL DATA: National Soil Survey Lab, Lincoln, NE.: data for this pedon S86IN-143-005; other NSSL data available: S82IN071-002, S92IN77-001; Agricultural Experiment Station Purdue University: File No's. BA7001, DC7613, JF7602, DC7703, DC7827 and DC8272, DC7702, RI7801, FR8101, SW8105.