LOCATION PERICO TX+OK
The Perico series consists of very deep, well drained, and moderately permeable soils. These soils formed in calcareous, loamy eolian sediments of Quaternary age. They are on nearly level to gently sloping eolian plains. Slopes range from 0 to 5 percent. Mean annual precipitation is 406 mm (16 in), and mean annual air temperature is 12 degrees C (54 degrees F).
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Aridic Paleustalfs
TYPICAL PEDON: Perico fine sandy loam - cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 18 cm (0 to 7 in), brown (7.5YR 5/4) fine sandy loam, brown (7.5YR 4/4) moist; weak fine granular structure; slightly hard, friable; few very fine calcium carbonate concretions; strongly effervescent, moderately alkaline; abrupt smooth boundary. (10 to 38 cm [4 to 15 in] thick)
Btk1--18 to 58 cm (7 to 23 in), brown (7.5YR 5/4) sandy clay loam, brown (7.5YR 4/4) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; many fine pores; few wormcasts; few patchy clay films; few films and threads of calcium carbonate on ped surfaces; violently effervescent, moderately alkaline; clear wavy boundary. (15 to 46 cm [6 to 18 in] thick)
Btk2--58 to 79 cm (23 to 31 in), light brown (7.5YR 6/4) sandy clay loam, brown (7.5YR 5/4) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; few fine roots; common fine and medium pores; patchy clay films; estimated 5 percent visible calcium carbonate films and threads on ped surfaces; violently effervescent; moderately alkaline; gradual smooth boundary. (15 to 46 cm [6 to 18 in] thick)
Btk3--79 to 109 cm (31 to 43 in), brown (7.5YR 5/4) sandy clay loam, brown (7.5YR 4/4) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable; common fine and medium pores; few patchy clay films; few films and threads of calcium carbonate on ped surfaces; violently effervescent, moderately alkaline; gradual smooth boundary. (13 to 43 cm [5 to 17 in] thick)
Btk4--109 to 175 cm (43 to 69 in), yellowish brown (10YR 5/4) sandy clay loam, dark yellowish brown (10YR 4/4) moist; weak coarse prismatic structure parting to weak medium subangular blocky; soft, very friable; few pores; few patchy clay films; few films and threads of calcium carbonate; strongly effervescent, moderately alkaline; gradual smooth boundary. (41 to 76 cm [16 to 30 in] thick)
2Btk5--175 to 224 cm (69 to 88 in), reddish yellow (7.5YR 6/6) clay loam, strong brown (7.5YR 5/6) moist; weak medium subangular blocky structure; slightly hard, friable; few patchy clay films; estimated 5 percent calcium carbonate as films, threads, and nodules; violently effervescent, moderately alkaline.
TYPE LOCATION: Dallam County, Texas; 6 miles northeast of the intersection of U.S. Highways 54 and 87 in Dalhart on Highway 54; 150 ft south into cultivated field. Latitude: 36 degrees 6 minutes, 48.3 seconds North; 102 degrees 26 minutes, 27.6 minutes West; Dalhart East USGS quad; NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture: An ustic moisture regime bordering on aridic. The soil moisture control section is dry in some or all parts for more than 180 but less than 220 days, cumulative, in normal years.
Precipitation Pattern: Precipitation is typically uniform throughout most of the year with rainfall the highest from April through October. Average snowfall is about 457 mm (18 in) annually from November through April.
Mean annual soil temperature: 12 to 14 degrees C (54 to 59 degrees F)
Depth to argillic horizon: 10 to 38 cm (4 to 15 in)
Depth to visible secondary carbonates: 10 to 30 cm (4 to 12 in)
Depth to calcic horizon: 61 to more than 203 cm (24 to 80 in)
Solum thickness: more than 203 cm (80 in)
Particle-size control section: 18 to 35 percent silicate clay.
Ap or A horizon:
Hue: 7.5YR or 10YR
Value: 5 or 6
Chroma: 2 to 4.
Texture: loamy fine sand, fine sandy loam, or loam.
Note: Where moist color value and chroma are less than 3.5, thickness of the A horizons is less than 18 cm (7 in).
Btk and 2Btk horizons:
Hue: 5YR, 7.5YR or 10YR
Value: 5 or 6
Chroma: 4 to 6.
Texture: sandy clay loam or clay loam.
Visible secondary calcium carbonates: 3 to 25 percent by volume. Some pedons have a calcic horizon at depths of 61 cm (24 in) or greater.
COMPETING SERIES: These are the
Rickmore series. Similar soils also include the
Dallam series: have horizons in the upper solum that are non-effervescent.
Predawn series: have cooler mean annual air temperatures and fewer frost-free days.
Rickmore series: have chroma less than 5 in the upper 150 cm of argillic horizon; in addition have more than 35 percent silicate clay in the lower argillic horizon.
Dalhart series: have a clay decrease of 20 percent from the maximum within 150 cm of the mineral soil surface.
Vingo series: have coarse-loamy particle size class.
Parent material: loamy eolian deposits of Quaternary age.
Landform: nearly level to gently sloping plains.
Slopes: dominantly 1 to 3 percent, but range from 0 to 5 percent
Mean annual precipitation: 381 to 432 mm (15 to 17 in)
Mean annual air temperature: 11 to 14 degrees C (52 to 57 degrees F)
Frost-free period: 165 to 185 days
Elevation: 1128 to 1707 m (3,700 to 5,600 ft.)
Thornthwaite P-E Index: 12 to 17
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing
Rickmore series. Also included are the
Spurlock, Valerian (T), and
Dallam soils: are on similar to slightly higher landscape positions
Rickmore soils: are on similar landscape positions.
Dalupe soils: are on narrow floodplains of draws and do not have argillic horizons.
Karde soils: are on playa dunes and have fine-silty particle size class.
Spurlock soils: are on draws or valley sides slopes and have carbonatic mineralogy and coarse-loamy particle size class.
Valerian (T) soils: are on eolian dunes and do not have argillic horizons.
Vingo soils: are on slightly higher landscape positions and have a coarse-loamy particle size control section
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is negligible on 0 to 1 percent slopes and low on 1 to 5 percent slopes. Permeability is moderate.
USE AND VEGETATION: Used mostly for rangeland, but a few areas are used for wheat and grain sorghum. Vegetation consists of sideoats grama, blue grama, little bluestem, sand drop seed, and sand sagebrush. This soil has been correlated to the Sandy Loam (R077BY021TX) and Sandy (R077BY658TX) ecological site in MLRA-77B.
DISTRIBUTION AND EXTENT: Southern High Plains, Northwestern Part (MLRA 77B in LRR H) of Texas and New Mexico north of the Canadian River. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Dallam County, Texas; 1970
REMARKS: These soils were formerly included in the Ulysses series.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 18 cm (0 to 7 in) (Ap horizon)
Argillic horizon: 18 to 224 cm (7 to 88 in) (Btk horizons).
ADDITIONAL DATA: None
Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014
National Cooperative Soil Survey