LOCATION HIDALGO TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, hyperthermic Typic Calciustolls
TYPICAL PEDON: Hidalgo sandy clay loam--cropland.
(Colors are for dry soil unless otherwise stated.)
Ap--0 to 9 inches; dark grayish brown (10YR 4/2) sandy clay loam, very dark grayish brown (10YR 3/2) moist; weak subangular blocky and granular structure; hard, friable; few small fragments
of shell; calcareous; moderately alkaline; clear smooth boundary.
(5 to 9 inches thick)
A1--9 to 17 inches; dark grayish brown (10YR 4/2) sandy clay loam; very dark grayish brown (10YR 3/2) moist; weak subangular blocky structure; hard, friable; many fine and very fine pores;
few earthwormcasts; calcareous; moderately alkaline; diffuse
smooth boundary. (6 to 10 inches thick)
B2--17 to 28 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 4/3) moist; moderate fine subangular blocky structure; hard, friable; many fine and very fine pores; few threads and
films of segregated calcium carbonate; few earthwormcasts; few fragments of snail shell; calcareous; moderately alkaline; diffuse smooth boundary. (7 to 16 inches thick)
B2ca--28 to 38 inches; pale brown (10YR 6/3) clay loam, dark brown (10YR 4/3) moist; weak subangular blocky structure; hard, friable; many fine and very fine pores; few fragments of snail
shell; about 10 percent by volume of soft bodies of calcium carbonate; calcareous; moderately alkaline; diffuse smooth
boundary. (8 to 16 inches thick)
Cca--38 to 85 inches; very pale brown (10YR 7/3) clay loam, brown (10YR 5/3) moist; massive; hard, friable; many fine and very fine pores; few fragments of snail shell; about 10 percent by
volume of soft bodies of calcium carbonate.
TYPE LOCATION: Hidalgo County, Texas; 1.8 miles northwest of
Donna, Texas; in a cultivated field, 300 feet west of county road
and 1.3 miles north of its intersection with U. S. Highway 83;
this intersection is 1.1 miles (via U. S. 83) west of Main Street
in Donna.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 30 to 50 inches. Secondary lime in the form of films and threads or soft masses occur at depths ranging from 12 to 28 inches. Electrical conductivity in most pedons ranges from 1 to 4 millimhos per cm,
but in some saline pedons the range is up to about 16 millimhos.
The A horizon is dark grayish brown (10YR 4/2), grayish brown
(10YR 5/2), or brown (10YR 4/3, 5/3). Moist values are less than 3.5. It is sandy clay loam or fine sandy loam.
The B horizon is brown (10YR 5/3; 7.5YR 5/4), pale brown (10YR
6/3), light brownish gray (10YR 6/2), light brown (7.5YR 6/4), or grayish brown (10YR 5/2). It is sandy clay loam or clay loam with clay range of 23 to 35 percent.
The C horizon is very pale brown (10YR 7/3), pale brown (10YR
6/3), light brownish gray (10YR 6/2), brown (7.5YR 5/4), light
brown (7.5YR 6/4), or light gray (10YR 7/2). The C horizon is
sandy clay loam or clay loam, with 5 to 35 percent of weakly
cemented concretions and soft bodies of calcium carbonate.
COMPETING SERIES: These are the
Castroville,
Engle,
Raymondville,
Uvalde, and
Venus series. Castroville and Uvalde soils have fine-silty 10 to 40 inch control sections. In addition, Uvalde
soils are dry in the moisture control section for longer periods. Engle and Venus soils have mean annual soil temperatures less than
72 degrees F. Raymondville soils have more than 35 percent clay
in the 10 to 40 inch control section.
GEOGRAPHIC SETTING: Hidalgo soils are on nearly level to gently sloping deltas or coastal terraces. Slope gradients are mostly
less than 2 percent, but range up to about 5 percent. The soil formed in moderately fine textured calcareous sediments. The
climate is subtropical. The average annual precipitation range
from 24 to 32 inches, the mean annual temperature about 74 degrees F., and Thornthwaite annual P-E indices range from 28 to 38.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing
Raymondville series and the
Brennan and
Willacy series. Brennan
and Willacy soils have Bt horizons and are noncalcareous in the
upper part of the solum. These soils occur on similar surfaces.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeablity. When irrigated, water may accumulate at depths of 4
to 8 feet below the surface.
USE AND VEGETATION: Much of this soil is cleared, cultivated, and irrigated. Irrigated crops are cotton, grain sorghum, vegetables, sugar cane, and citrus. Dryland farming is practiced in some
areas. Native grasses are four-flower trichloris, Arizona
cottontop, lovegrass tridens, plains bristlegrass, and hooded windmillgrass, and there is an overstory of a wide variety of
thorny shrubs and prickly pear.
DISTRIBUTION AND EXTENT: Rio Grande Plain of Texas and possibly Mexico. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Hidalgo County, Texas; 1925.
REMARKS: Formerly classified in the Calcisol great soil group.