LOCATION LAPARITA TX
Established Series
Rev. WJG-WMR-KBH
11/2010
LAPARITA SERIES
The Laparita series consists of very deep, well drained, moderately slowly permeable soils that formed in loamy and clayey alluvium over residuum of the Jackson Group. These nearly level to gently sloping soils are on headslopes, toeslopes and footslopes of interfluves. Slopes range from 0 to 3 percent but are mainly less than 2 percent. Mean annual precipitation is about 610 mm (24 in) and mean annual temperature is about 22.2 degrees C (72 degrees F).
TAXONOMIC CLASS: Fine, smectitic, hyperthermic Pachic Vertic Argiustolls
TYPICAL PEDON: Laparita loam, on a south facing, convex, headslope in rangeland; elevation is 85 meters (278 feet). (Colors are for dry soil unless otherwise stated.)
A--0 to 20 cm (0-8 in); dark gray (10YR 4/1) loam, black (10YR 2/1) moist; moderate fine and medium subangular blocky structure; very hard, firm; thin crust on surface; upper 2.5 cm (1 in) is slightly platy and of slightly lighter color; many fine roots; few fine pores and old root channels; slightly acid; clear smooth boundary. (10 to 25 cm [4 to 10 in] thick)
Bt--20 to 41cm (8 to 16in); very dark gray (10YR 3/1) clay, black (10YR 2/1) moist; moderate medium subangular blocky structure parting to moderate fine angular blocky; very hard; very firm; common fine roots; few fine pores and old root channels; few pressure faces; distinct clay films on surfaces of peds;; slightly saline; neutral; gradual smooth boundary. (8 to 51 cm [3 to 20 in] thick)
Btk--41 to 56 cm (16 to 22 in); dark gray (10YR 4/1) clay, very dark gray (10YR 3/1) moist; moderate fine and medium subangular blocky structure parting to moderate very fine angular blocky; very hard; very firm; few fine roots, fine pores, and old root channels; few pressure faces; distinct clay films on surfaces of peds; few threads and one millimeter size masses of calcium carbonate; moderately saline; noncalcareous; moderately alkaline; gradual wavy boundary. (13 to 53 cm [5 to 21 in] thick)
BCkz1--56 to 76 cm (22 to 30 in); pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; moderate fine and medium subangular blocky structure; hard, firm; few pressure faces; contains about 2 to 3 percent by volume of small masses and threads and films of calcium carbonate and other salts; moderately saline; matrix is noncalcareous; moderately alkaline; gradual wavy boundary. (0 to 76 cm [0 to 30 in] thick)
BCkz2--76 to 117 cm (30 to 46 in); pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; weak fine and medium subangular blocky structure; hard, friable; contains a few small masses and threads of calcium carbonate and other salts; moderately saline; matrix is noncalcareous; moderately alkaline; clear wavy boundary. (0 to 46 cm [0 to 18in] thick)
2Cdkyz--117 to 183 cm (46 to 72 in); light gray (2.5Y 7/2) clay loam intermingled with noncemented claystone masses fragments, light brownish gray (10YR 6/2) moist; common fine distinct mottles of light yellowish brown and light olive brown; massive; contains many gypsum crystals and many threads and pockets of neutral salts and few threads of calcium carbonate; moderately saline: the soft shale is noncalcareous; moderately alkaline.
TYPE LOCATION: Atascosa County, Texas; approximately 6.6 miles southwest of Campbellton on Farm Road 791; 0.6 mile south to 7-4 ranch headquarters; 1.4 miles south through corrals and along fenceline; 100 feet east in rangeland. McCoy, Texas USGS topographic quadrangle; Latitude: 28 degrees, 46 minutes, 54.083 seconds N; Longitude, 98 degrees, 15 minutes, 29.224 seconds W.; NAD83.
RANGE IN CHARACTERISTICS:
Soil Moisture: A typic-ustic moisture regime. The soil moisture control section is dry in some or all parts for more than 90 days but less than 180 cumulative days in normal years. June through August and December through February are the driest months. These soils are intermittently moist in September through November and March through May.
Solumn thickness: 100 to 150 cm (40 to 60 in)
Mean annual soil temperature: 22 to 24 degrees C. (72 to 76 degrees F.)
Depth to argillic: 10 to 115 cm (4 to 46 in)
Depth to secondary calcium carbonate: more than 36 cm (14 in)
Particle-size control section (weighted average)
Clay content: 35 to 60 percent
A Horizon
Hue: 10YR
Value: 2 to 4 dry
Chroma: 1 to 2 dry
Texture: loam, sandy clay loam, or clay loam
EC (dS/m): less than 2 dS/m
Reaction: Slightly acid or neutral
Bt and Btk Horizons
Hue: 10YR
Value: 2 to 6 dry
Chroma: 1 to 3 dry
Texture: clay loam, sandy clay, or clay
EC (dS/m): 4 to 12
Reaction: neutral to moderately alkaline
Identifiable secondary carbonate: amount 0 to 5 percent,
BCkz Horizon
Hue: 10YR or 2.5Y
Value: 5 to 8 dry
Chroma: 1 to 4 dry
Texture: sandy clay loam, clay loam, or clay
EC (dS/m): 6 to 16
Identifiable secondary carbonate: amount 1 to 5
Salt accumulations: amount 1 to 5
2Cdkyz Horizon
Hue: 2.5Y or 5Y
Value: 5 to 7 dry
Chroma: 2 to 4 dry
Texture: clay loam, clay, or silty clay
COMPETING SERIES: These are the
Coy and
Marcelinas series. Similar soils are the
Clareville,
Elmendorf,
Topia,
Tordia, and
Zavco series.
Clareville and Zavco soils: have COLE less than 0.07.
Coy soils: are calcareous throughout.
Elmendorf and Marcelinas soils: have thicker sola and are not saline.
Topia soils: have soil temperatures of less than 22 degrees C (72 degrees F.)
Tordia soils: do not have an argillic horizon.
GEOGRAPHIC SETTING: Parent material: clayey and loamy slope alluvium over residuum derived from the Jackson Group.
Landform: toeslopes and footslopes of interfluves
Slope: 0 to 3 percent
Mean annual air temperature range: 21 to 23 degrees C (70 to 74 degrees F)
Mean annual precipitation range: 610 to 762 mm (24 to 30 in)
Frost-free period: 240 to 260 days
Elevation: 52 to 183 m (175 to 600 ft)
Thornthwaite annual P-E indices: 28 to 40
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Clareville (TX),
Coy (TX),
Tordia (TX),
Campbellton (TX),
Fashing (TX),
Monteola (TX),
Orelia (TX), and
Willamar (TX) series.
Campbellton and Fashing soils: occur at higher elevations.
Monteola, Orelia, and Willamar soils: are on about the same, or slightly lower, position in the landscape.
Campbellton, Coy, Fashing, and Monteola soils: are calcareous.
Campbellton soils: have COLE values less than 0.07.
Fashing soils: do not have an argillic horizon and have sola less than 51 cm (20 in) thick over claystone sediments.
Monteola soils: are Vertisols.
Orelia soils: have an ochric epipedon and a fine-loamy particle-size control section.
Willamar soils: have an ochric epipedon and have more than 15 percent exchangeable sodium in the B and C horizon.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately slow. Runoff is negligible on 0 to 1 percent slopes and very low on 1 to 3 percent slopes. Some areas rarely flood during high rainfall events caused by unusual weather events such as tropical storms.
USE AND VEGETATION: Mainly used for rangeland. A few areas are cultivated in the eastern extent of the soil range. Crops grown are mainly small grain, grain sorghum, and introduced grasses. Present vegetation includes pink pappusgrass, threeawn, red grama, curlymesquite, Hall panicum, and bristlegrass. Woody plants include running mesquite, twisted acacia, mesquite, white brush, lotebush condalia, agarito, wolfberry, spiny hackberry, and paloverde.
DISTRIBUTION AND EXTENT: Northern Rio Grande Plain of Texas; LRR I; MLRA 83A; The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Atascosa County, Texas, MLRA 83A, 1977.
REMARKS: Laparita soils were formerly included in the Orelia series. The Orelia series has a fine-loamy control section. This soil has a fine control section as well as Vertic Properties. The classification was changed to include the pachic vertic subgroup which is current with the Eleventh Edition of Keys to Soil Taxonomy.
Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 20 to 56 cm (8 to 22 in) (Bt and Btk horizons)
Mollic epipedon: The zone from 0 to 56 cm (0 to 22 in) (A, Bt, and Btk horizon).
Argillic horizon: The zone from 20 to 56 cm (8 to 22 in) (Bt and Btk horizon).
Vertic feature: The presence of pressure facesat 20 to 76 cm (8 and 30 in).(Bt,Btk,and BCkz1 horizons)
Lithologic discontinuity: Occurs at 117 cm
ADDITIONAL DATA: Local lab data from the McMullen project office available on pedons from McMullen County.
TAXONOMIC VERSION: Keys to Soil Taxonomy, Eleventh Edition, 2010.
National Cooperative Soil Survey
U.S.A.