LOCATION AMBIA TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, nonacid, thermic Vertic Fluvaquents
TYPICAL PEDON: Ambia clay loam--pasture.
(Colors are for moist soil unless otherwise stated.)
A11-- 0-7 inches, very dark grayish brown (10YR 3/2)
clay loam; weak fine granular structure; very hard, firm; common
fine roots; few fine pores; slightly acid; clear smooth boundary.
(4 to 7 inches thick)
A12g-- 7-16 inches, grayish brown (10YR 5/2) clay loam;
few fine distinct dark yellowish brown mottles; moderate fine and medium subangular blocky structure; extremely hard, very firm, plastic; common fine roots; few fine pores; few black concretions; very strongly acid; gradual smooth boundary. (0 to 12 inches
thick)
IIA11bg-- 16-33 inches, dark grayish brown (10YR 4/2) clay; common medium distinct dark yellowish brown (10YR 4/4) mottles and common medium faint gray (10YR 5/1) mottles; moderate medium subangular blocky structure; extremely hard, very firm, plastic;
few fine black concretions; strongly acid; gradual smooth
boundary. (12 to 32 inches thick)
IIA12bg-- 33-69 inches, dark gray (10YR 4/1) clay; common medium faint dark grayish brown (10YR 4/2) mottles and few fine distinct dark brown and dark yellowish brown mottles; weak coarse blocky structure parting to moderate medium subangular blocky structure; extremely hard, very firm, plastic; few slickensides;
few fine black concretions; medium acid; diffuse wavy boundary.
(20 to 41 inches thick)
IIIA1bg-- 69-96 inches, very dark gray (10YR 3/1) clay; few fine faint dark brown mottles; weak coarse blocky structure; extremely hard, very firm, plastic; common intersecting
slickensides; few fine pockets of white neutral salts; few fine
black concretions; neutral.
TYPE LOCATION: Lamar County, Texas; from the intersection of U.S. Highway 271 and North Loop 286 in Paris, 6.8 miles north on U.S. Highway 271, 3.9 miles east on Farm Road 2648, 2.6 miles north on county road, 0.5 mile northeast, 2.4 miles south, and east and 400 yards east in Pine Creek flood plain.
RANGE IN CHARACTERISTICS: The A horizon is very dark gray (10YR 3/1), very dark grayish brown (10YR 3/2), dark grayish brown (10YR 4/2), grayish brown (10YR 5/2), dark brown (10YR 3/3), or brown
(10YR 4/3). Horizons having values, moist, of less than 4 are
less than 7 inches thick. Mottles are few or common, fine or
medium, very dark grayish brown (10YR 3/2), dark grayish brown
(10YR 4/2), grayish brown (10YR 5/2), brown (10YR 4/3, 5/3), or
dark yellowish brown (10YR 3/4, 4/4). Texture is clay loam, silty clay loam, or silty clay. Reaction is very strongly acid through neutral.
The IIAbg horizons are dark grayish brown (10YR 4/2; 2.5Y 4/2) or grayish brown (10YR 5/2; 2.5Y 5/2) with common fine or medium
mottles of dark gray (10YR 4/1), gray (10YR 5/1), brown (10YR 4/3, 5/3; 7.5YR 4/4), yellowish brown (10YR 5/4, 5/6), dark yellowish brown (10YR 4/4, 3/4), or strong brown (7.5YR 5/6). Texture is
clay or silty clay. Reaction is very strongly acid through
slightly acid. In places it is medium acid or slightly acid in
the subhorizon. The control section averages 40 to 60 percent, by weight, clay.
The IIIA1bg horizon is very dark gray (10YR 3/1; 5Y 3/1), dark
gray (10YR 4/1; 5Y 4/1), or dark grayish brown (10YR 4/2; 2.5Y
4/2). Most pedons contain few or common, fine or medium, red or brown mottles. Texture is clay or silty clay. Reaction is
strongly acid through neutral.
COMPETING SERIES: Competing series are the
Alligator,
Gentilly,
Gladewater,
Houlka,
Iberia,
Ijam, Lacroix,
Leeper,
Roxton,
Sharkey,
Tuscumbia,
Una, and
Urbo series.
Alligator, Gentilly, and Sharkey soils have a very-fine textured control section, and Alligator soils are at least strongly acid throughout the control section. Gladewater, Leeper, and Tuscumbia soils have no erratic distribution of organic matter. Gladewater soils are grayer than Ambia soils. Tuscumbia soils have mixed mineralogy. Houlka, Una, and Urbo soils have an acid control section. Una and Urbo soils have mixed mineralogy and have no
vertic properties. Iberia and Roxton soils have a mollic
epipedon. Ijam soils are saturated 3 to 6 months each year, are grayer, and are neutral through strongly alkaline throughout. Lacroix soils have no vertic properties.
GEOGRAPHIC SETTING: Ambia soils are on flood plains that drain foreste uplands and blackland prairies. Slope is dominantly less than 1 percent, but ranges to 2 percent. These soils formed in clayey alluvium. Near the type location the average annual precipitation
is about 45 inches, the average annual temperature is about 63 degrees F., and the Thornthwaite P-E index is about 68.
GEOGRAPHICALLY ASSOCIATED SOILS: Associated soils are the competing Roxton and the Nahatche series. Nahatche soils have a fine-loamy control section.
DRAINAGE AND PERMEABILITY: Ambia soils are somewhat poorly
drained and have very slow runoff, internal drainage, and permeability. During the cool season, the soil floods 3 to 5
times each year for periods of 2 to 7 days.
USE AND VEGETATION: These soils are used mainly as woodland and pasture. Wooded areas support such mixed hardwoods as water oak, willow oak, hackberry, elm, ash, honey locust, osage orange, and hickory. Pastures are such introduced grasses as bermudagrass, dallisgrass, and fescue.
DISTRIBUTION AND EXTENT: Ambia soils are in the northeastern part
of Texas and possibly in the southern part of Oklahoma. The
series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Lamar County, Texas; 1975.
REMARKS: These soils were classified in the Alluvial great soil group. They were included in the Iuka series.