LOCATION PATOUTVILLE             LA

Established Series
Rev. DRM, JDS
10/2018

PATOUTVILLE SERIES


The Patoutville series consists of very deep, somewhat poorly drained, slowly permeable soils that formed in loess. These soils are on nearly level to very gently sloping terraces. Mean annual temperature near is 68 degrees F. near the type location, and mean annual rainfall is about 60 inches.

TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Aeric Epiaqualfs

TYPICAL PEDON: Patoutville silt on a broad, nearly level area in a pasture at an elevation of 39 feet. (Colors are for moist soil unless otherwise stated.)

Ap1--0 to 8 inches; grayish brown (10YR 5/2) silt; weak fine granular structure; very friable; many fine and medium roots; many distinct dark yellowish brown (10YR 4/4) iron oxidation stains along root channels; strongly acid; abrupt smooth boundary.

Ap2--8 to 11 inches; grayish brown (10YR 5/2) silt loam; moderate medium granular structure; friable; many fine and medium roots; many fine and medium iron-manganese concretions throughout; many distinct dark yellowish brown (10YR 4/4) masses of iron accumulation throughout; many fine faint light brownish gray (10YR 6/2) iron depletions throughout; moderately acid; clear smooth boundary. (Combined thickness of the A and Ap horizons ranges from 3 to 12 inches)

Btg1--11 to 15 inches; dark grayish brown (10YR 4/2) silt loam; weak medium subangular blocky structure; friable; many fine and medium roots; few faint clay films on faces of peds; few fine prominent yellowish brown (10YR 5/8) and common medium distinct dark yellowish brown (10YR 4/4) masses of iron accumulation throughout; many medium distinct light brownish gray (10YR 6/2) iron depletions throughout; strongly acid; clear wavy boundary.

Btg2--15 to 22 inches; dark grayish brown (10YR 4/2) silty clay loam; moderate medium prismatic structure parting to moderate medium subangular blocky; firm; few fine and medium roots; many distinct dark gray (10YR 4/1) clay films on faces of peds; many fine and medium iron-manganese concretions throughout; many medium prominent red (2.5YR 4/6 and 2.5YR 4/8) and brownish yellow (10YR 6/8) masses of iron accumulation throughout; moderately acid; clear wavy boundary (Combined thickness of the Btg horizon is 5 to 18 inches)

Bt--22 to 28 inches; brown (10YR 5/3) silty clay loam; moderate coarse prismatic structure parting to moderate medium subangular blocky; firm; few fine and medium roots; many distinct dark gray (10YR 4/1) clay films on faces of peds; many fine and medium moderately cemented iron-manganese concretions throughout; many medium distinct brownish yellow (10YR 6/6) masses of iron accumulation throughout; common fine prominent reddish brown (2.5YR 4/4) masses of iron accumulation throughout; few medium prominent yellowish red (5YR 5/6) masses of iron accumulation throughout; slightly acid; clear wavy boundary. (5 to 20 inches thick)

B'tg1--28 to 38 inches; light brownish gray (2.5Y 6/2) silt loam; weak coarse prismatic structure parting to moderate medium subangular blocky; firm; few fine and medium roots; many distinct dark gray (10YR 4/1) clay films on faces of peds; many fine and medium moderately cemented iron-manganese concretions throughout; many medium prominent yellowish brown (10YR 5/6 and 10YR 5/8) masses of iron accumulation throughout; few fine prominent yellowish red (5YR 5/6) masses of iron accumulation throughout; slightly acid; gradual wavy boundary.

B'tg2--38 to 51 inches; grayish brown (2.5Y 5/2) silt loam; weak coarse prismatic structure parting to moderate medium subangular blocky; firm; many fine and very fine discontinuous tubular pores; many distinct dark gray (10YR 4/1) clay films on faces of peds; many distinct dark gray (10YR 4/1) silt coatings on faces of peds; many medium prominent yellowish brown (10YR 5/8) and dark yellowish brown (10YR 4/6) masses of iron accumulation throughout; slightly acid; gradual wavy boundary.

B't--51 to 68 inches; variegated, 35% yellowish brown (10YR 5/6), 35% brownish yellow (10YR 6/6), and 30% light brownish gray (2.5Y 6/2) silt loam; weak coarse prismatic structure parting to moderate medium subangular blocky; firm; many distinct dark gray (10YR 4/1) clay films on faces of peds; many distinct dark gray (10YR 4/1) silt coatings on faces of peds; the areas with brownish yellow color are iron accumulations, and the areas with light brownish gray color are iron depletions; also has many medium prominent yellowish brown (10YR 5/8) and dark yellowish brown (10YR 4/6) masses of iron accumulation throughout; slightly acid; gradual wavy boundary. (Combined thickness of the B'tg and B't horizons ranges from 20 to 60 inches.)

2Bt--68 to 83 inches; variegated, 35% gray (10YR 6/1), 35% brownish yellow (10YR 6/6), and 30% yellowish brown (10YR 5/6) silt loam; weak coarse prismatic structure parting to moderate medium subangular blocky; firm; common fine and very fine discontinuous tubular pores; thick distinct clay films on faces of peds; common medium dark colored moderately cemented iron and manganese concretions throughout; the areas with brownish yellow color are iron accumulations, and the areas with gray color are iron depletions; neutral. (0 to 20 inches thick).

TYPE LOCATION: Acadia Parish, Louisiana; 2.5 miles north-northeast of Mire; 0.85 miles east of State Highway 95; then 50 feet south of Parish Road P2-20; 30 feet south and 1700 feet west of the northeast corner of sec. 29, T.8 S., R.3 E.; USGS Mire, Louisiana 7.5 minute topographic quadrangle; 30 degrees 20 minutes 05 seconds N. Latitude, and 92 degrees 10 minutes 52 seconds W. Longitude, NAD 83.

RANGE IN CHARACTERISTICS: The thickness of the solum ranges from 50 to more than 80 inches. Depth to the 2Bt horizon is 60 to more than 80 inches. Typically, these soils have less than 10 percent sand throughout the solum. The calcium-magnesium ratio is 1 or more. Reaction ranges from very strongly acid to slightly alkaline in the A and E horizons. In nonirrigated areas, the A and E horizons are typically very strongly acid to slightly acid. Reaction ranges from strongly acid to neutral in the Btg and Bt horizons; and from slightly acid to moderately alkaline in the underlying horizons.

The A or Ap horizon has hue of 10YR, value of 3 or 4 and chroma of 1 to 3, or value of 5 and chroma of 2 or 3. Where value is 3, the A or Ap horizon is less than 6 inches thick. Texture is silt or silt loam.

The Eg horizon, where present, has hue of 10YR, value of 4 to 6, and chroma of 1 or 2; or hue of 2.5Y, value of 4 or 5, and chroma of 2. Texture is silt loam.

The Btg and B'tg horizons have ped interiors that have hue of 10YR, value of 4 or 6, and chroma of 1 or 2; or hue of 2.5Y or 5Y, value of 5 or 6, and chroma of 1 or 2. Red masses of iron accumulation are diagnostic for the series and are present in some part of the Btg or B'tg horizon. Iron accumulations in shades of brown, and iron depletions in shades of gray are present in most pedons. Peds are coated with clay films in shades of brown or gray. Texture is silt loam or silty clay loam.

The Bt and B't horizons have ped interiors that have hue of 10YR or 2.5Y, value of 5 or 6, and chroma of 3 to 6. Red masses of iron accumulation are diagnostic for the series and are present in some part of the Bt or B't horizon. Iron accumulations in shades of brown, and iron depletions in shades of gray are present in most pedons. Peds are coated with clay films in shades of brown or gray. Texture is silt loam or silty clay loam.

The 2Bt horizon has hue of 10YR to 5Y, value of 5 or 6, and chroma of 1 to 6; or it is variegated with these colors. Iron accumulations in shades of brown, and iron depletions in shades of gray are present in most pedons. Texture is silt loam, silty clay loam, or silty clay.

The BC and C horizons, where present, have hue of 10YR to 5Y, value of 5 or 6, and chroma of 1 to 6; or they are variegated with these colors. Iron accumulations in shades of brown, and iron depletions in shades of gray are present in most pedons. Texture is silt loam, silty clay loam, or silty clay.

COMPETING SERIES: These are the Acy, Essen, Frozard, and Solier series in the same family. The Galvez, Kurk, and McGehee series are in a closely related families. Acy and Essen soils do not have red iron accumulations and contain calcium carbonate concretions. Frozard, and Galvez soils do not have red iron accumulations in the subsoil. Solier soils have a discontinuity to a buried albic horizon and an argillic horizon with albic intrusions at 12 to 24 inches deep. Kurk and McGehee soils have an active activity class, formed in alluvium or alluvium over loess, and have a lithologic discontinuity.

GEOGRAPHIC SETTING: Patoutville soils are on nearly level to gently sloping terraces. These soils formed in loess. The climate is humid temperate. Average annual precipitation ranges from 55 to 65 inches and mean annual temperature ranges from 60 to 70 degrees F.. Frost free days range from 235 to 350. Elevation ranges from 5 to 80 feet.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Crowley, Duson, Frost, and Jeanerette series. Crowley soils have more than 35 percent clay in the upper 20 inches of the argillic horizon, and have an abrupt textural change. In addition, Crowley soils are on slightly lower landscape positions. Frost and Jeanerette soils are in depressions and along drainageways. In addition, Frost soils are poorly drained, and Jeanerette soils have a mollic epipedon. Duson soils are on side slopes and convex ridges, and do not have aquic conditions in the upper 5 inches of the argillic horizon.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Patoutville soils are wet in the layers below 0.5 to 3.0 feet, and moist in the layers below the discontinuity. Runoff is slow. Permeability is slow.

USE AND VEGETATION: Most areas are now used for pasture, or for growing sugarcane, sweet potatoes, soybeans, grain sorghum, wheat, and rice, in rotation with crayfish. Tall grasses were once the dominant native vegetation.

DISTRIBUTION AND EXTENT: South Louisiana. The series is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: AUBURN, ALABAMA

SERIES ESTABLISHED: St. Mary Parish, Louisiana; 1953.

REMARKS: The CEC:Clay ratio for this pedon is 0.58, which is slightly below the range for the superactive activity class. It was felt that this is within the range of lab error, however, and data from similar soils indicate that soils on these landscapes and parent materials are tending more towards the superactive class.
Diagnostic horizons and properties in this soil include:

Ochric epipedon - from a depth of 0 to 11 inches (Ap1 and Ap2 horizons).
Argillic horizon - from a depth of 11 to 83 inches (Btg, Bt, B'tg, B't, and 2Bt horizons).
Red masses of iron accumulation - from a depth of 15 to 28 inches (Btg2, Bt, and B'tg1 horizons).
Lithologic Discontinuity - at 68 inches (top of 2Bt horizon)

ADDITIONAL DATA: Laboratory data on the typifying pedon were obtained from the National Soil Survey Laboratory, sample number S93LA001-16.

MLRA=134


National Cooperative Soil Survey
U.S.A.