LOCATION PIDCOKE TX
Established Series
Rev. GLL:CLN
04/2022
PIDCOKE SERIES
The Pidcoke series consists of shallow, well drained, moderately slowly permeable soils derived from marly marine sediments over indurated fossiliferous limestone. These occur on summits of knolls and low hills. The slope range is 1 to 3 percent. Mean annual precipitation is 660 to 864 mm (26 to 34 in), and mean annual air temperature is about 17.8 to 20 degrees C (64 to 68 degrees F).
TAXONOMIC CLASS: Loamy, carbonatic, thermic Lithic Calciustolls
TYPICAL PEDON: Pidcoke clay loam, on a convex 2 percent slope in rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 18 cm (0 to 7 in); dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky and granular structure; hard, friable; common very fine and fine roots; common fine concretions of calcium carbonate; about 5 percent by volume fossil shells from 3 to 38 mm (1/8 to 1 1/2 in across); strongly effervescent; moderately alkaline; clear smooth boundary. (Thickness is 10 to 30 cm [4 to 12 in].)
Bk--18 to 33 cm (7 to 13 in); grayish brown (10YR 5/2) gravelly clay loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky; hard, friable; common very fine and fine roots; common fine concretions and few films and threads of calcium carbonate; about 25 percent by volume fossil shells from 3 to 38 mm (1/8 to 1 1/2 in across); strongly effervescent; moderately alkaline; abrupt smooth boundary. (Thickness is 15 to 20 cm [6 to 8 in].)
R--33 to 76 (13 to 30 in); indurated fossiliferous limestone; massive and unfractured; hardness of about 3 by Mohs scale.
TYPE LOCATION: Coryell County, Tx; from the intersection of Texas Highway 36 and Farm Road 2955 about 11 miles north of Gatesville; 0.4-mile northwest on Texas Highway 36; 0.6 mile south on county road; 75 feet northwest in rangeland. USGS topographic quadrangle: Ater, Texas; Latitude: 31 degrees, 34 minutes, 12.82 seconds N; Longitude: 97 degrees, 50 minutes, 47.13 seconds W; Datum: WGS84. UTM Easting 609469.75 m, UTM Northing 3493377.45 m, UTM Zone 14.
RANGE IN CHARACTERISTICS:
Soil Moisture: Ustic soil moisture regime. The soil moisture control section is dry in some or all parts for more than 90, but less than 120 days in normal years.
Depth to lithic contact: 25 to 51 cm (10 to 20 in)
Depth to secondary calcium carbonate: 10 to 30 cm (4 to 12 in)
Depth to calcic horizon: 10 to 30 cm (4 to 12 in)
Thickness of the mollic epipedon: 18 to 33 cm (7 to 13 in)
Particle-size control section (weighted average)
Clay content: 20 to 35 percent
Rock fragments: 1 to 25 percent
A horizon
Hue: 7.5YR or 10YR
Value: 3 or 4
Chroma: 2 or 3
Texture: clay loam, silty clay loam, or their gravelly counterparts
Clay content: 20 to 35 percent
Rock fragments: 1 to 25 percent; 3 to 38 mm; fossil shells
Calcium carbonate equivalent: 40 to 60 percent
Effervescence: strong
Reaction(pH): moderately alkaline (7.9 to 8.4)
Bk
Hue: 7.5YR or 10YR
Value: 4 to 6
Chroma: 2 to 4
Texture: clay loam, silty clay loam, or their gravelly counterparts
Clay content: 20 to 35 percent
Rock fragments: 1 to 25 percent; 3 to 38 mm; fossil shells
Identifiable secondary carbonate: 2 to 20 percent, 0.2 to 2 mm, concretions, films, and threads
Calcium carbonate equivalent: 40 to 60 percent
Effervescence: strong to violent
Reaction(pH): moderately alkaline (7.9 to 8.4)
R layer
Indurated limestone. The limestone is cemented beds of fossilized oyster shells. The beds are about 61 to 610 cm (2 to 20 ft) thick and have thin marl or shale seams at vertical intervals of about 30 to 91 cm (1 to 3 ft).
COMPETING SERIES:
Similar soils are the
Cho,
Doss,
Maloterre,
Purves,
Real and
Tarrant series.
Cho,
Doss, and
Real soils: are underlain by a paralithic contact, and in addition Real soils have skeletal control sections.
Maloterre soils: are very shallow soils that have an ochric epipedon.
Purves and
Tarrant soils: are clayey, montmorillonitic. In addition, Tarrant soils have a skeletal control section.
GEOGRAPHIC SETTING:
Parent material: Residuum derived from Walnut Clay Geologic Formation of the Lower Cretaceous Period
Landscape: Hills
Landform: summits of low hills and knolls
Slope: 1 to 3 percent
Precipitation Pattern: The majority of the yearly amount occurs during the fall and spring months. The winter and summer months are normally drier.
Mean annual precipitation: 660 to 864 mm (26 to 34 in)
Thornthwaite P-E Index: 44 to 56
Mean annual air temperature: 17.8 to 20 degrees C (64 to 68 degrees F)
Frost-free period: 197 to 263 days
Elevation: 190.5 to 457.2 m (472.4 to 1500 ft)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Brackett,
Cho,
Maloterre, and
Topsey series.
Brackett and
Maloterre soils: have light colored surfaces and are below or on similar positions.
Cho soils: are on ridgetops at lower elevations.
Topsey soils: are deep loamy soils on slopes below the Pidcoke soils.
DRAINAGE AND PERMEABILITY: Well drained, Permeability is moderately slow. Runoff is slow to medium.
USE AND VEGETATION: Mainly range. Native vegetation includes little bluestem, sideoats grama, Texas wintergrass, buffalograss and threeawn. Woody vegetation includes scattered live oak and juniper.
DISTRIBUTION AND EXTENT: Grand Prairie Land Resource Area in Central Texas; LRR J; MLRA 85; The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Coryell County, Texas; 1983.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Particle size control section: 0 to 33 cm (0 to 13 in). (A and Bk horizons)
Mollic epipedon - 0 to 18 cm (0 to 7 in)(A horizon)
Calcic horizon - 18 to 33 cm (7 to 13 in) (Bk horizon)
Lithic contact - Soil and limestone interface at 33 cm (13 in)
Additional Comments:
ADDITIONAL DATA: S2017TX497034
Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014
National Cooperative Soil Survey
U.S.A.