LOCATION ESTACADO                TX+NM

Established Series
Rev. FBP-RM-TCB
09/2022

ESTACADO SERIES

The Estacado series consists of very deep, well drained, moderately slowly permeable soils that formed in calcareous, loamy eolian deposits of the Blackwater Draw Formation of Pleistocene age. These soils are on nearly level to gently sloping plains and playa slopes. Slope ranges from 0 to 5 percent. Mean annual precipitation is 483 mm (19 in) and mean annual air temperature is 16 degrees C (61 degrees F).

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, thermic Aridic Paleustolls

TYPICAL PEDON: Estacado clay loam, on a level plain, 0.5 percent slopes in cropland at an elevation of about 1,166 m (3,825 ft). (Colors are for dry soil unless otherwise stated.)

Ap--0 to 15 cm (0 to 6 in); dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; hard, firm; many fine roots; many fine and medium tubular pores; slightly effervescent; moderately alkaline; clear smooth boundary. (13 to 25 cm thick)

Bt1--15 to 48 cm (6 to 19 in); brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; very hard, firm; many fine and medium roots between peds; many very fine and fine tubular pores; few distinct clay films on faces of peds; few fine masses of calcium carbonate; strongly effervescent; moderately alkaline; clear wavy boundary. (13 to 51 cm thick)

Bt2--48 to 97 cm (19 to 38 in); brown (7.5YR 4/4) clay loam, dark brown (7.5YR 3/4) moist; weak coarse prismatic structure parting to weak fine subangular blocky; hard, firm; common very fine and fine roots between peds; many very fine and fine tubular pores; few distinct clay films on faces of peds; few fine nodules of calcium carbonate; strongly effervescent; moderately alkaline; gradual irregular boundary. (30 to 89 cm thick)

Btk--97 to 127 cm (38 to 50 in); reddish yellow (7.5YR 7/6) clay loam, reddish yellow (7.5YR 6/6) moist; weak coarse prismatic structure parting to weak fine subangular blocky; hard, firm; common very fine and fine roots between peds; many fine and medium tubular pores; few distinct clay films on faces of peds; about 40 percent calcium carbonate by volume as masses, nodules, and finely disseminated carbonates; violently effervescent; moderately alkaline; gradual wavy boundary. (38 to 64 cm thick)

Btkk--127 to 203 cm (50 to 80 in); pinkish white (7.5YR 8/2) clay loam; pinkish gray (7.5YR 7/2) moist; weak coarse prismatic structure parting to weak fine and medium subangular blocky; hard, firm; common very fine and fine roots between peds; many fine and medium tubular pores; few distinct clay films on faces of peds; about 55 percent calcium carbonate by volume as masses, nodules, and finely disseminated carbonates; violently effervescent; moderately alkaline.

TYPE LOCATION: Deaf Smith County, Texas; from the intersection of U.S. Highway 385 and U.S. Highway 60 in Hereford, 6.75 miles north on U.S. Highway 385, 3 miles east on county road, 0.5 mile north on county road, 600 ft east in cropland; Latitude: 34 degrees, 54 minutes, 56.3 seconds N; Longitude: 102 degrees, 20 minutes, 56.1 seconds W; Hereford NE, Texas 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. July through August and December through
February are the driest months. These soils are intermittently moist in September through November and March through June.
Mean annual soil temperature: 15 to 18 degrees C (59 to 64 degrees F).
Depth to argillic horizon: 13 to 25 cm (5 to 10 in).
Depth to secondary calcium carbonate: 13 to 61 cm (5 to 24 in).
Depth to calcic horizon: 63 to 100 cm (25 to 40 in).
Solum thickness: more than 203 cm (80 in).
Particle-size control section: 18 to 35 percent silicate clay.

A horizon
Hue: 7.5YR or 10YR
Value: 3 to 5, 2 to 4 moist
Chroma: 2 or 3
Texture: loam, clay loam
Effervescence: slight to violent
Reaction: slightly alkaline or moderately alkaline

Bt horizons
Hue: 7.5YR or 10YR
Value: 4 to 6, 3 to 5 moist
Chroma: 3 to 6
Texture: sandy clay loam, clay loam
Visible calcium carbonate: less than 2 percent as films, filaments, or nodules
Effervescence: slight or strong
Reaction: slightly alkaline or moderately alkaline

Btk horizons
Hue: 7.5YR or 10YR
Value: 4 to 7, 3 to 6 moist
Chroma: 3 to 6
Texture: sandy clay loam, clay loam
Visible calcium carbonate: 5 to 48 percent by volume as films, filaments, masses, and nodules
Calcium carbonate by weight: 3 to 35 percent
Effervescence: strong or violent
Reaction: moderately alkaline

Btkk horizon
Hue: 7.5YR or 10YR
Value: 4 to 8, 3 to 7 moist
Chroma: 1 to 4
Texture: sandy clay loam, clay loam
Visible calcium carbonate: 50 to 70 percent by volume as films, filaments, masses, nodules, and finely disseminated carbonates
Calcium carbonate by weight: 40 to 60 percent
Effervescence: violent
Reaction: moderately or strongly alkaline

COMPETING SERIES: This is the Acuff series. Similar soils also include the Bovina (T-TX), Mansker, Pep, Portales, and Tulia series.
Acuff soils: noncalcareous in the upper horizons and have a calcic horizon between 76 to 150 cm (30 and 60 in).
Bovina soils: have a calcic horizon less than 61 cm (24 in) from the top of the mineral soil surface.
Mansker and Tulia soils: have carbonatic mineralogy; in addition, Tulia soils do not have a mollic epipedon.
Pep and Portales soils: have a calcic horizon at a depth less than 61 cm (24 in) and do not have an argillic horizon.

GEOGRAPHIC SETTING:
Parent material: calcareous, loamy eolian deposits from the Blackwater Draw Formation of Pleistocene age.
Landform: on nearly level to gently sloping plains and playa slopes.
Slopes: 0 to 5 percent.
Mean annual air temperature: 14 to 17 degrees C (57 to 63 degrees F).
Mean annual precipitation: 432 to 533 mm (17 to 21 in).
Frost-free period: 185 to 220 days.
Elevation: 823 to 1,615 m (2,700 to 5,300 ft).
Thornthwaite annual P-E Index Values: 25 to 36.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Acuff, Bovina, Mansker, Pep, and Portales soils and the Amarillo, Olton, Pantex, Pep, Posey, and Pullman soils.
Acuff, Bovina, Mansker, Pep, and Tulia soils: are on similar landscape positions.
Amarillo, Olton, Pantex, and Pullman soils: are on similar landscape positions and are noncalcareous in the surface and upper argillic horizons Portales soils: are on slightly lower landscape positions and do not have an argillic horizon.
Posey soils: are on similar landscape positions, have a calcic horizon within 24 in of the soil surface, and do not have a mollic epipedon.

DRAINAGE AND PERMEABILITY: Well drained and moderately slow permeable. Surface runoff is negligible on 0 to 1 percent slopes and low on 1 to 5 percent slopes.

USE AND VEGETATION: Mainly used for crop production. Principal crops grown are cotton, grain sorghum, and wheat. Climax vegetation in rangeland is mainly mid and short grasses and includes blue grama, sideoats grama, and buffalograss, with lesser amounts of vine-mesquite, western wheatgrass, galleta or tobosa, silver bluestem, wild alfalfa, and prairieclover with a light to moderate overstory of mesquite. This soil has been correlated to the Deep Hardland (R077CY022TX) ecological site in MLRA-77C.

DISTRIBUTION AND EXTENT: The Southern High Plains, Southern Part (MLRA 77C in
LRR H) of western Texas and eastern New Mexico. The soil is moderately extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Hale County, Texas; 1969.

REMARKS: These soils were previously included with the Portales and Mansker series.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 48 cm (0 to 19 in). (Ap, Bt1 horizons)
Argillic horizon: 15 to 203 cm (6 to 80 in). (Bt1, Bt2, Btk1, Btk2 horizons)
Calcic horizon: 97 to 203 cm (38 to 80 in). (Btk1, Btk2 horizons)
Plugged (kk) horizon: 127 to 203 cm (50 to 80 in) (Btkk1, Btkk2)
Note: the kk feature is defined as pedogenic carbonate accumulation that is characterized by laterally continuous carbonates that have engulfed rock, sand, silt, and clay particles; plugged the macroporosity of the soil horizon with 50 percent or more calcium carbonate; and obliterated the original soil structure.

ADDITIONAL DATA: ARS Bushland Experiment Station data from Deaf Smith County, TX (S91TX-117-001); KSSL data from Carson County, TX (S93TX-065-001) (69L007-69L010).

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014.

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National Cooperative Soil Survey
U.S.A.