LOCATION CHRISTINE TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, hyperthermic Pachic Argiustolls
TYPICAL PEDON: Christine clay loam--rangeland.
(Colors are for dry soil unless otherwise stated.)
A1--0 to 5 inches; grayish brown (10YR 5/2) clay loam, very
dark grayish brown (10YR 3/2) moist; weak subangular blocky structure; hard, friable; common fine roots; few fine pores;
slightly acid; abrupt smooth boundary. (3 to 10 inches thick)
B21t--5 to 23 inches; dark gray (10YR 4/1) clay loam, very
dark gray (10YR 3/1) moist; weak coarse prismatic structure
parting to moderate medium blocky; extremely hard, very firm; few roots between peds; patchy clay films on faces of prisms; neutral; gradual smooth boundary. (10 to 20 inches thick)
B22t--23 to 31 inches; gray (10YR 5/1) clay loam, dark gray (10YR 4/1) moist; weak fine subangular blocky structure; hard, friable; mildly alkaline; gradual smooth boundary. (6 to 20
inches thick)
B3--31 to 46 inches; light brownish gray (10YR 6/2) clay
loam, grayish brown (10YR 5/2) moist; weak fine subangular blocky structure; hard, friable; about 5 percent weakly cemented calcium carbonate concretions; soil matrix is noncalcareous; moderately alkaline; diffuse wavy boundary. (6 to 24 inches thick)
C--46 to 72 inches; pale brown (10YR 6/3) clay loam, brown
(10YR 5/3) moist; massive; friable; few fine weakly cemented
calcium carbonate concretions; soil matrix is noncalcareous, moderately alkaline.
TYPE LOCATION: Atascosa County, Texas; 5.2 miles west on Farm
Road 791 from its junction with U.S. Highway 281 at north edge of Campbellton, 100 feet north in rangeland.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 30 to 50 inches. Depth to secondary carbonates ranges from 16 to 38
inches. The soil is slightly to moderately saline and increases
with depth. Exchangeable sodium is 3 to about 12 percent.
The A horizon ranges from gray to very dark grayish brown; hues
are 10YR or 2.5Y, chromas 1 and 2, and values 3 through 5 to a
depth of 10 inches or more. It is loam, clay loam, or sandy clay loam. Soil salinity is less than 2 millimhos per centimeter. It
is slightly acid through moderately alkaline.
The B21t horizon is very dark gray or dark gray in hues of 10YR or 2.5Y, chromas 1 or less, and values 3 or 4. It is clay loam,
sandy clay loam, or sandy clay. Clay content of the upper 20
inches of the Bt horizon averages 25 to 35 percent. Some pedons
have B21t horizons of sandy clay or clay loam with more than 35 percent clay that are less than 10 inches thick. Prism tops are commonly slightly rounded and the upper surface is coated with a sandy film (skeletans). Soil salinity increases with depth and ranges from 4 to about 16 millimhos per centimeter. It is neutral through moderately alkaline.
The B22t and B3 horizons range from dark gray to grayish brown;
hues are 10YR or 2.5Y, and chromas are 1 through 3. It is clay
loam or sandy clay loam. Salinity ranges from 4 to 16 millimhos
per centimeter. It is mildly or moderately alkaline. Few to
about 5 percent soft bodies and fine concretions of calcium
carbonate and a few gypsum crystals and other neutral salts occur mainly in the lower part.
The C horizon is gray to very pale brown loam, clay loam, or sandy clay loam. It contains few to about 3 percent soft bodies and concretions of calcium carbonate. A few gypsum crystals and other neutral salts occur in most pedons.
COMPETING SERIES: These include the
Czar and
Racombes series in
the same family and the
Clareville,
Cuero, and
Smithville series
in similar families. Clareville soils have more than 35 percent
clay in the upper 20 inches of the Bt horizon. Cuero, Czar, Smithville, and Racombes soils have less than 4 percent
exchangeable sodium and have less than 4 millimhos salinity in the upper 20 inches of the Bt horizon and they have different native plant communities. In addition, Cuero and Smithville soils have
mean annual soil temperatures less than 72 degrees F.
GEOGRAPHIC SETTING: Christine soils occupy nearly level, slightly concave, weakly expressed drainageways and nearly level low
terraces on uplands adjacent to the drainageways. Slopes are
mainly less than 1.0 percent. The soil formed in clayey and loamy marine sediments. The mean annual temperature is 71 degrees to 74 degrees F. Average annual precipitation ranges from 22 to 32
inches and the Thornthwaite P-E index ranges from 28 to 40.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the
Amphion,
Hanis,
Imogene,
Laparita,
Monteola and
Papalote series. All these soils occur on adjoining areas at slightly higher elevations and
all these soils, except Imogene soils, have clayey control
sections. Monteola soils are calcareous and have intersecting slickensides. Imogene and Papalote soils lack mollic epipedons.
In addition, Papalote soils have mottled Bt horizons.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow runoff; slow permeability.
USE AND VEGETATION: Mainly rangeland. A few areas are cultivated
to small grain, grain sorghum and forage crops. Native grasses
are mainly pink pappusgrass, two and fourflower trichloris, vine-mesquite, threeawn, hooded windmillgrass, bristlegrass and buffalograss. Woody vegetation is mainly huisache, mesquite,
retama, spiny hackberry, whitebrush and pricklypear.
DISTRIBUTION AND EXTENT: North-central part of the Rio Grande
Plain of Texas. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Atascosa County, Texas; 1977.
REMARKS: Christine soils were formerly mapped as a depressional phase of the Orelia series and would have been included in the Planosol great soil group.