LOCATION LAGLORIA TXEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, active, hyperthermic Torrifluventic Haplustepts
TYPICAL PEDON: Lagloria silt loam in cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 15 cm (0 to 6 in); light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; structureless; hard, friable, slightly sticky and slightly plastic; many fine roots and pores; few very fine flakes of mica; few wormcasts; strongly effervescent, moderately alkaline; clear smooth boundary. (10 to 20 cm [4 to 8 in] thick)
A--15 to 38 cm (6 to 15 in); light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak subangular blocky structure; hard, friable, sticky and slightly plastic; many fine roots and pores; few flakes of mica; few wormcasts; strongly effervescent, moderately alkaline; clear wavy boundary. (10 to 31 cm [4 to 12 in] thick)
Bk--38 to 114 cm (15 to 45 in); light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak subangular blocky structure; hard, friable, sticky and slightly plastic; many fine roots and pores; few streaks of brown, few flakes of mica; 10 percent threads and films of calcium carbonate in lower part; violently effervescent, moderately alkaline; gradual wavy boundary. (64 to 102 cm [25 to 40 in] thick)
C--114 to 203 cm (45 to 80 in); light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; thin strata of silty clay loam and very fine sandy loam; massive; hard, very friable, slightly sticky and slightly plastic; common fine pores; violently effervescent, moderately alkaline.
TYPE LOCATION: Starr County, Texas; 3.3 miles east of the intersection of U.S. Highway 83 and Farm Road 775 in Rio Grande City and 50 feet south of U.S. Highway 83 into field. Rio Grande City South, Texas USGS topographic quadrangle. Latitude: 26 degrees, 21 minutes, 13.79 seconds, N; Longitude: 98 degrees, 46 minutes, 18.007 seconds, W; NAD 83.
RANGE IN CHARACTERISTICS:
Soil Moisture: An ustic soil moisture regime bordering on aridic. The soil moisture control section remains moist in some or all parts for less than 90 consecutive days in normal years. The soil is driest during the months of June through August and December through February. These soils are intermittently moist in September through November and March through May.
Solum thickness: 89 to 152 cm (35 to 60 in)
Mean annual soil temperature: 22 to 24 degrees C (72 to 76 degrees F).
Depth to cambic horizon: 20 to 51 cm (8 to 20 in)
Particle-size control section (weighted average)
Clay content: 8 to 18 percent
CEC/clay ratio: 0.40 to 0.60
A horizon
Hue: 10YR
Value: 5 to 7. When moist color values are less than 3.5, the A horizon is less than 10 inches thick.
Chroma: 2 or 3
Texture: very fine sandy loam, loam, or silt loam
Clay content: 8 to 18 percent
Base saturation: 100 percent
Calcium carbonate equivalent: 5 to 15 percent
EC (dS/m): 0 to 4
Effervescence: slightly to strongly effervescent
Reaction: moderately alkaline
Bk or Bw horizon, where present
Hue: 10YR
Value: 6 or 7
Chroma: 2 to 4
Texture: very fine sandy loam, loam, or silt loam
Clay content: 8 to 18 percent
Base saturation: 100 percent
Calcium carbonate equivalent: 5 to 30 percent
Identifiable secondary carbonate: 0 to 19 percent, fine and medium, in the form of films, threads, masses, on surfaces of peds and in ped interiors. A calcic horizon occurs in some pedons below 40 inches of the surface.
EC(dS/m): 0 to 4
Effervescence: moderately or strongly effervescent
Reaction: moderately alkaline
The C horizon is stratified and individual stratum are clayey, loamy, or sandy similar in color to the B horizon. Some pedons have slightly darker Ab horizons at depths of 20 and 30 inches.
COMPETING SERIES: There are no competing series in the same family. Similar soils are the
Ashbough (MT),
Atco (TX),
Conalb (TX),
Hindman (TX),
Laredo (TX),
McAllen (TX), and
Reynosa (TX) series.
Ashbough soils: are in the fine-loamy family and have frigid soil temperature regime
Atco and Conalb soils: have carbonatic mineralogy
Hindman soils: have a thermic soil temperature regime
Laredo and Reynosa soils: are in the fine-silty family and in addition Laredo soils have a mollic epipedon
McAllen soils: are in the fine-loamy family and do not have stratification
GEOGRAPHIC SETTING:
Parent material: calcareous silty alluvium derived from mixed sources
Landform: stream terraces
Slope: 0 to 3 percent
Mean annual air temperature: 21 to 23 degrees C (70 to 74 degrees F).
Mean annual precipitation: 406 to 686 mm (16 to 27 in)
Precipitation pattern: moist spring and fall months and dry winter and summer months.
Frost-free period: 240 to 360 days
Elevation: 61 to 198 m (200 to 650 ft)
Thornthwaite annual P-E indices: 24 to 28
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Laredo,
Reynosa,
Rio Grande, and
Zalla series.
Laredo and Reynosa soils: occur on similar positions.
Rio Grande and Zalla soils: occur on floodplains
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible on slopes less than 1 percent and low on 1 to 3 percent slopes.
USE AND VEGETATION: Used as irrigated cropland, wildlife habitat, or rangeland. Irrigation water is available in all cropland areas. A few areas were cropped without irrigation in the past. The main crops are cotton, grain sorghum, and a wide variety of cool-season vegetables. Native grasses consist of trichloris, tanglehead, cottontop, and bristlegrass. Woody species include large mesquite trees, spiny hackberry, lotebush, blackbrush, hackberry, and Texas ebony. The ecological site is Loamy Bottomland 20-35 PZ (R083DT505TX).
DISTRIBUTION AND EXTENT: Lower Rio Grande Plain, Texas; LRR I; MLRA 83D; the series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Maverick County, Texas, 1972.
REMARKS: Classification change from Fluventic Ustochrepts to Torrifluventic Haplustepts based on application of the second edition of Soil Taxonomy, 1999.
Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 25 to 102 cm (10 to 40 in)
Ochric epipedon: 0 to 38 cm (0 to 15 in). (A horizons)
ADDITIONAL DATA: The assignment of the cation-exchange activity class is inferred from lab data from surrounding surveys.
TAXONOMIC VERSION: Keys to Soil Taxonomy, Tenth Edition, 2006.