LOCATION HEBBRONVILLE TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, active, hyperthermic Aridic Haplustalfs
TYPICAL PEDON: Hebbronville loamy fine sand--rangeland.
(Colors are for dry soil unless otherwise stated.)
A1--0 to 3 inches; pale brown (10YR 6/3) loamy fine sand,
dark brown (10YR 4/3) moist; very weak subangular blocky
structure; soft, very friable; many roots; many fine pores;
neutral, clear smooth boundary. (2 to 5 inches thick)
A2--3 to 15 inches; brown (10YR 5/3) loamy fine sand, dark
brown (10YR 3/3) moist; weak subangular blocky structure; soft,
very friable; many roots; many fine pores; neutral; gradual wavy boundary. (10 to 15 inches thick)
Bt--15 to 38 inches; brown (10YR 5/3) fine sandy loam, dark brown (10YR 4/3) moist; weak fine subangular blocky structure;
soft, very friable; patchy clay films on faces of peds and in
pores; few roots; many fine pores; threads and films of calcium carbonate in lower part; mildly alkaline; diffuse wavy boundary.
(18 to 27 inches thick)
Btk--38 to 60 inches; light yellowish brown (10YR 6/4) fine sandy loam, dark yellowish brown (10YR 4/4) moist; structureless; soft, friable; few soft bodies of calcium carbonate; calcareous; moderately alkaline; gradual wavy boundary. (14 to 30 inches
thick)
Bk--60 to 70 inches; very pale brown (10YR 7/4) fine sandy
loam, yellowish brown (10YR 5/4) moist; massive; slightly hard, friable; few soft bodies of calcium carbonate; calcareous;
moderately alkaline.
TYPE LOCATION: Jim Hogg County, Texas; in a pasture 50 feet west
of Farm Road 649 which point is 4.3 miles south of intersection of Farm Road 649 and Texas Highway 16. The community name at this intersection is Randado which point is 23 miles via Texas Highway
16 southwest of Hebbronville.
RANGE IN CHARACTERISTICS: Depth to the Bk horizon ranges from 45
to 75 inches. Secondary lime occurs at depths of 14 to 60 inches.
The A horizon is pale brown (10YR 6/3), grayish brown (10YR 5/2), dark grayish brown (10YR 4/2), or brown (10YR 5/3; 7.5YR 5/2). It
is fine sandy loam or loamy fine sand. Reaction is neutral to
mildly alkaline.
The Bt horizon is brown (10YR 5/3; 7.5YR 5/2, 5/4), yellowish
brown (10YR 5/4), light yellowish brown (10YR 6/4), or pale brown (10YR 6/3). It is fine sandy loam or loam with a clay content of
12 to 18 percent and from 3 to 6 percent (absolute) more clay than the A horizon. Reaction of the Bt horizon is neutral to
moderately alkaline.
The Bk horizon is very pale brown (10YR 7/3, 7/4), pale brown
(10YR 6/3), light yellowish brown (10YR 6/4), brownish yellow
(10YR 6/6), or yellow (10YR 7/6). It is fine sandy loam, sandy
clay loam, or loam. It is moderately alkaline and calcareous.
COMPETING SERIES: These include
Brennan,
Comitas,
McAllen, and
Willacy series. Brennan and Willacy soils have finer textured subsoils, and in addition, Willacy soils have more than one
percent organic matter in the epipedons. Comitas soils have
surface textures coarser than loamy very fine sand that extend to depths of more than 20 inches. McAllen soils lack an argillic horizon and are calcareous throughout.
GEOGRAPHIC SETTING: Nearly level to gently undulating uplands. Surfaces are plane to weakly convex. Slopes range up to 5 percent but are mostly under 2 percent. Climate is semiarid to dry
subhumid. The mean annual rainfall ranges from 18 to 28 inches;
the mean annual air temperature ranges from 70 to 74 degrees F. Thornthwaite annual P-E index ranges from 24 to 34.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Brennan, Comitas, McAllen, and Willacy series and Ramadero series. Brennan, Comitas, and McAllen soils occur on similar surfaces. Ramadero soils occur in weakly expressed drainageways, have mollic epipedons thicker than 20 inches, and finer textured subsoils.
DRAINAGE AND PERMEABILITY: Well drained; runoff is slow. Permeability is moderately rapid.
USE AND VEGETATION: Used mainly for rangeland; few areas
cultivated. Native vegetation consists of four-flower trichloris, Arizona cottontop, Plains bristlegrass, hooded windmillgrass, pink pappusgrass and woody shrubs such as mesquite, pricklypear, Texas ebony, tasajillo, and granjeno.
DISTRIBUTION AND EXTENT: Occurs in southwestern part of Rio
Grande Plain of south Texas. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Jim Hogg County, Texas; 1970.