LOCATION DOUBLEGATES AL+MS

Established Series
SP, GRB
09/2013

DOUBLEGATES SERIES

The Doublegates series consists of very deep, poorly drained, moderately slowly permeable soils along drainageways and in depressions. They formed in thick loamy marine and alluvial sediments of the Southern Coastal Plain. Near the type location, the mean annual precipitation is about 60 inches and the mean annual temperature is about 65 degrees F. Slopes range from 0 to 3 percent.

TAXONOMIC CLASS: Fine-silty, siliceous, semiactive, thermic Plinthic Paleaquults

TYPICAL PEDON: Doublegates silt loam - forested (Colors are for moist soil).

A--0 to 1 inch; brown (10YR 5/3) silt loam; weak fine subangular structure; very friable; many very fine, fine, medium and coarse roots; extremely acid; clear smooth boundary. (1 to 5 inches thick)

Eg--1 to 5 inches; light brownish gray (10YR 6/2) silt loam; weak medium subangular blocky structure; very friable; many very fine, fine, medium and coarse roots; common medium prominent yellowish brown (10YR 5/6) masses of iron accumulation; few medium faint gray (10YR 6/1) areas of iron depletions; extremely acid; clear wavy boundary. (0 to 5 inches thick)

EBg--5 to 14 inches; light brownish gray (10YR 6/2) silt loam; moderate fine and medium subangular blocky structure; friable; common very fine, fine and medium roots, few coarse roots; few sand grains coated and bridged with clay; common medium prominent yellowish brown (10YR 5/6) and strong brown (7.5YR 5/6) masses of iron accumulation; common medium faint gray (10YR 6/1) areas of iron depletions; extremely acid; clear wavy boundary. (0 to 10 inches thick)

Btvg1--14 to 21 inches; light brownish gray (10YR 6/2) silt loam; weak coarse angular blocky structure parting to moderate fine and medium subangular blocky; friable; common very fine and fine roots, few medium and coarse roots; sand grains coated and bridged with clay; about 10 percent, by volume, plinthite nodules ranging from 5 to 20 mm in size; many medium prominent yellowish brown (10YR 5/6) masses of iron accumulation; many medium faint gray (10YR 6/1) areas of iron depletions; extremely acid; gradual smooth boundary.

Btvg2--21 to 39 inches; about 40 percent gray (10YR 6/1), 30 percent light brownish gray (10YR 6/2), 20 percent yellowish brown (10YR 5/4) and 10 percent strong brown (7.5YR 5/6) silty clay loam; moderate medium subangular blocky structure; firm; few fine, medium and coarse roots; about 25 percent, by volume, plinthite nodules ranging from 5 to 20 mm in size; common distinct clay films on faces of peds; the areas of yellowish brown and strong brown are iron accumulations and the areas of gray and light brownish gray are iron depletions; very strongly acid; gradual wavy boundary.

Btvg3--39 to 48 inches; about 35 percent gray (10YR 6/1), 30 percent light brownish gray (10YR 6/2), 20 percent yellowish brown (10YR 5/4) and 15 percent red (2.5YR 4/6) silty clay loam; moderate medium subangular blocky structure; firm; few fine and medium roots; about 20 percent, by volume, plinthite nodules ranging from 5 to 15 mm in size; few faint clay films on faces of peds; the areas of yellowish brown and red are iron accumulations and the areas of gray and light brownish gray are iron depletions; very strongly acid; gradual wavy boundary. (Combined thickness of the Btvg horizons range from 24 to 54 inches in thickness)

Btv1--48 to 62 inches; about 40 percent red (2.5YR 4/6), 35 percent gray (10YR 6/1), 15 percent yellowish brown (10YR 5/4) and 5 percent strong brown (7.5YR 5/6) and about 5 percent yellowish brown (10YR 5/6) clay loam; moderate medium subangular blocky structure; firm; few fine roots; about 15 percent, by volume, plinthite nodules ranging from 5 to 15 mm in size; few faint clay films on faces of peds; the areas of red, yellowish brown and strong brown are iron accumulations and the areas of gray are iron depletions; very strongly acid; gradual wavy boundary.

Btv2--62 to 80 inches; about 30 percent light brownish gray (10YR 6/2), 25 percent yellowish brown (10YR 5/4), 10 percent strong brown (7.5YR 5/6), and 10 percent red (2.5YR 4/6) clay loam; moderate medium subangular blocky structure; firm; few fine roots; about 15 percent, by volume, plinthite nodules ranging from 5 to 15 mm in size; the areas of light brownish gray are iron depletions and the areas of yellowish brown, strong brown and red are iron accumulations; very strongly acid.

TYPE LOCATION: Washington County, Alabama. Approximately 1.5 miles north of McIntosh; about 2,200 feet south and 1,300 feet west of the northeast corner of Section 24, T. 4 N., R. 1 W; USGS McIntosh topographic quadrangle; Lat. 31 degrees 17 minutes 57.1 seconds N.; Long. 86 degrees 01 minute 01 second W.

RANGE IN CHARACTERISTICS: Solum thickness is more than 60 inches. Reaction ranges from extremely acid to strongly acid throughout except where the surface has been limed.

The A or Ap horizon has hue of 10YR or 2.5Y, value of 2 to 5, and chroma of 1 to 3. Texture is very fine sandy loam or silt loam.

The Eg horizon, where present, has hue of 10YR or 2.5Y, value of 4 to 6, and chroma of 1 or 2. Masses of iron accumulation in shades of yellow and brown range from none to common. Texture is very fine sandy loam or silt loam.

The Bg horizon, where present, has hue of 10YR or 2.5Y, value of

The EBg or BEg horizon, where present, has hue of 10YR or 2.5Y, value of 5 to 7 and chroma of 1 or 2; or it is neutral with value of 5 to 7. Redoximorphic features in shades of yellow, brown and gray range from few to many. The upper 20 inches of the argillic horizon has more than 30 percent silt. Texture is silt loam or loam.

The Btvg horizon has hue of 10YR or 2.5Y, value of 5 to 7 and chroma of 1 or 2; or it is neutral with value of 5 to 7. Many pedons have no dominant color and are multicolored in shades of yellow, brown and gray. Redoximorphic features in shades of yellow, brown and gray range from few to many. The upper 20 inches of the argillic horizon has more than 30 percent silt. Texture is silt loam, loam, silty clay loam or clay loam.

The Btv horizon, where present, has hue of 10YR or 2.5Y, value of 5 to 7 and chroma of 3 to 6; or it is neutral with value of 5 to 7. Many pedons have no dominant color and are multicolored in shades of red, yellow, brown and gray. Redoximorphic features in shades of yellow, brown and gray range from few to many. Texture is silty clay loam or clay loam.

COMPETING SERIES: There are no other known series in the same family.

GEOGRAPHIC SETTING: Doublegates soils are on nearly level stream terraces and slight depressions in the Southern Coastal Plain. Slopes range from 0 to 2 percent. They formed in loamy marine and alluvial Coastal Plain sediments. The mean annual temperature ranges from 62 to 67 degrees F, and the mean annual precipitation ranges from 55 to 65 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Atmore, Bibb, Daleville, Malbis, Robertsdale and Savannah soils. Atmore soils are on similar positions and have coarse-loamy control sections. Bibb soils are on slightly lower flood plain positions, contain less than 5 percent, by volume, plinthite in the control section and are less developed. Daleville soils are on similar positions and have less than 5 percent, by volume, plinthite in the subsoil. The moderately well or well drained Malbis soils are on higher adjacent positions. The somewhat poorly drained Robertsdale soils are on slightly higher positions. The moderately well drained Savannah soils are on adjacent higher positions and have brittle subsoils.

DRAINAGE AND PERMEABILITY: Poorly drained; moderately slow permeability.

USE AND VEGETATION: Most areas of Doublegates soils are in hardwood forest; some areas are bedded and planted to loblolly pine. A few areas are used for growing corn, soybeans, and small grains along with food plots for wildlife.

DISTRIBUTION AND EXTENT: Southern Coastal Plain of Alabama, possibly Florida and Mississippi. The series is of small known extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama.

SERIES ESTABLISHED: Washington County, Alabama, 2010.

REMARKS: Diagnostic horizons recognized in this pedon:

Ochric epipedon - the zone from the surface of the soil to 14 inches (A, Eg and BEg horizons).

Argillic horizon - the zone from 14 to 80 inches (Btvg1, Btvg2, Btvg3, Btv1 and Btv2 horizons).

Plinthic horizon - the zone from 14 to 80 inches (Btvg1, Btvg2, Btvg3, Btv1 and Btv2 horizons).

Aquults feature - dominant chroma of 2 or less in the matrix of the argillic horizon.

ADDITIONAL DATA: Characterization pedon - Washington County, Alabama. S09AL-129-003 (1-8). Sample by the soil laboratory, Agronomy and Soils Department, Auburn University; Auburn, Alabama.

The Doublegates series is in MLRA 133A.

National Cooperative Soil Survey
U.S.A.