LOCATION FRIO TX
Established Series
Rev. GLL-CLN-RM
08/2021
FRIO SERIES
The Frio series consists of very deep, well drained, moderately slowly permeable soils that formed in calcareous loamy and clayey alluvium. These nearly level to very gently sloping soils occur on flood plains. Slope ranges from 0 to 2 percent. Mean annual precipitation is about 864 mm (34 in) and the mean annual temperature is about 18.3 degrees C (65 degrees F).
TAXONOMIC CLASS: Fine, smectitic, thermic Cumulic Haplustolls
TYPICAL PEDON: Frio silty clay-occasionally flooded, wooded. (Colors are for dry soils unless otherwise stated.)
A1--0 to 20 cm (0 to 8 in); dark grayish brown (10YR 4/2) silty clay, very dark grayish brown (10YR 3/2) moist; moderate fine and medium granular structure; hard, firm; moderately sticky, moderately plastic; many fine, medium, few coarse roots; strong effervescence; moderately alkaline; clear smooth boundary.
A2--20 to 56 cm (8 to 22 in); dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate medium and coarse subangular blocky structure parting to moderate fine subangular blocky; hard, firm; moderately sticky, moderately plastic; many fine, medium, and few coarse roots; few fine shell fragments; strong effervescence; moderately alkaline; clear smooth boundary.
Bk1--56 to 74 cm (22 to 29 in); dark grayish brown (10YR 4/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium prismatic structure parting to moderate fine and medium subangular blocky; hard, firm; moderately sticky, moderately plastic; common fine, medium, and few coarse roots; common fine films and threads of calcium carbonate; few fine shell fragments; strong effervescence; moderately alkaline; gradual smooth boundary.
Bk2--74 to 102 cm (29 to 40 in); dark grayish brown (10YR 4/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium prismatic structure parting to moderate medium and coarse subangular blocky; hard, firm; moderately sticky, moderately plastic; common fine, medium, and few coarse roots; common fine films and threads of calcium carbonate; strong effervescence; moderately alkaline; gradual smooth boundary. (Combined thickness of the A horizons is 51 to 152 cm [20 to 60 in]).
Bk3--102 to 203 cm (40 to 80 in) thick; grayish brown (10YR 5/2) silty clay, dark grayish brown (10YR 4/2) moist; moderate medium and coarse prismatic structure parting to weak coarse blocky; hard, firm; moderately sticky, moderately plastic; few fine, medium, and coarse roots; many fine films and threads and a few soft masses of calcium carbonate; strong effervescence; moderately alkaline.
TYPE LOCATION: Coryell County, Texas; approximately 18 miles southeast of Gatesville, Texas. About 5.2 miles northeast of the intersection of Texas Highways 36 and 236, along Texas Highway 236; then 100 ft west of pavement in wooded area. This site is about 0.28 mile northeast of the north end of the Leon River Bridge in Mother Neff State Park.
USGS topographic quadrangle: Eagle Springs, TX;
Latitude: 31 degrees, 19 minutes, 2 seconds, N;
Longitude: 97 degrees, 28 minutes, 14 seconds, W
Decimal Degrees
Latitude: 31.3172226
Longitude: -97.4705582
Datum: WGS84
RANGE IN CHARACTERISTICS:
Depth to sand, gravel, or limestone contact: 203 to 914 cm (80 to 360 in)
Thickness of the mollic epipedon: more than 51 to 152 cm (20 to 60 in)
Shrink-swell: COLE ranges from about .04 to .09 in the upper 127 cm (50 in) but lacks a layer 51 cm (20 in) or thicker with COLE OF .07 or more.
Particle-size control section (weighted average)
Clay content: 35 to 42 percent
A Horizon:
Hue: 7.5YR, 10YR
Value: 3 to 5
Chroma: 2 or 3
Texture: clay, silty clay or silty clay loam, or clay loam; Some pedons have discontinuous, light colored, loamy strata less than 8 cm (3 in) thick
Clay content: 30 to 50 percent
Rock fragments: 0 to 15 percent by volume; chert or limestone gravel
Calcium carbonate equivalent: 15 to 40 percent
Effervescence: violent or strong
Reaction (pH): slightly alkaline to moderately alkaline (7.4 - 8.4)
Bk1 and Bk2 Horizon:
Hue: 7.5YR, 10YR
Value: 3 to 5
Chroma: 2 or 3
Texture: clay, silty clay or silty clay loam, or clay loam; Some pedons have discontinuous, light colored, loamy strata less than 8 cm (3 in) thick
Clay content: 30 to 50 percent
Rock fragments: 0 to 15 percent by volume; chert or limestone gravel
Calcium Carbonate masses and concretions; 0 to 5 percent
Calcium carbonate equivalent: 15 to 40 percent
Effervescence: violent or strong
Reaction (pH): slightly alkaline to moderately alkaline (7.4 - 8.4)
Bk3 horizons:
Hue: 7.5YR, 10YR
Value: 4 or 5
Chroma: 2 to 4
Texture: clay, silty clay or silty clay loam, or clay loam
Clay content: 30 to 50 percent
Rock fragments: 0 to 15 percent by volume; chert or limestone gravel
Calcium Carbonate masses and concretions; 5 to 30 percent
Calcium carbonate equivalent: 15 to 40 percent
Sodium adsorption ratio: 0 to 2
Effervescence: violent or strong
Reaction (pH): slightly alkaline to moderately alkaline (7.4 - 8.4)
COMPETING SERIES: There are no competing series in the same family. Similar soils are the
Bosque,
Clearfork, DeLeon,
Lewisville,
Oakalla,
Ovan, and
Port series.
Bosque,
Clearfork,
Lewisville,
Oakalla, and
Port soils: have less than 35 percent silicate clay in the particle-size control section
Deleon and
Ovan soils: have vertic properties
GEOGRAPHIC SETTING:
Parent material: calcareous loamy and clayey alluvium derived from claystone, limestone, and mudstone of cretaceous age.
Landscape: river valley and dissected plains
Landform: floodplain
Slope: 0 to 2 percent
Mean annual precipitation: 762 to 965 mm (30 to 38 in)
Thornthwaite P-E Index: 40 to 54
Mean annual air temperature: 17.8 to 19.4 degrees C (64 to 67 degrees F)
Frost-free period: 220 to 260 days
Elevation: 121.9 to 609.6 m (400 to 2000 ft)
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bosque, DeLeon,
Rumley, and
Slidell series.
Bosque soils: occur on similar or slightly higher floodplain positions.
DeLeon soils: occur on slightly lower floodplain positions.
Gowen soils: occur on similar floodplain positions, do not have carbonates, and have a fine-loamy particle-size control section
Rumley soils: have higher carbonate levels and occur on first level terraces above the floodplain.
Slidell soils: have vertic properties and occur on head slopes and draws above the floodplain.
Trinity soils: have vertic properties, a very-fine particle-size control section and occur on lower moderately well drained areas of the floodplain
DRAINAGE AND PERMEABILITY:
Drainage class: Well.
Permeability class: Moderately slow.
Runoff: low on 0 to less than 1 percent slopes and medium on 1 to 2 percent slopes.
Flooding: soil floods unless protected, as seldom as once in about 100 years and as often as one to three times a year.
Wetness: Most areas have ground water within a depth of 6.1 m (20 ft). The
USE AND VEGETATION: Used for pasture, cropland, and range. Small grain, corn, and grain sorghum are the main crops. The main native grasses are big and little bluestem, switchgrass, indiangrass, Texas wintergrass, and Virginia wildrye. Native trees are mainly pecan, elm and oak.
DISTRIBUTION AND EXTENT:
General area: Mainly in North-central and Central Texas
Land Resource Region: J - Southwestern Prairies Cotton and Forage Region
Major Land Resource Area: Primarily in MLRA 85 - Grand Prairies, with small extent in MLRA 86 - Blackland Prairies
Extent: large
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Reconnaissance Survey of Southwest Texas; 1911.
REMARKS: The control section averages 34.1 percent silicate clay and 35.6 percent total clay. We classified this series in a fine family, and carbonate clay was not considered.
11/2014 RFG/SCP: Changed to tabular format and included metric values. Updated competing series, geographic setting, and associated soils sections.
03/2021 CMR/SCP: Changed A3 and A4 horizons to Bk1 and Bk2 horizons based on the soil structure and secondary carbonates. Added calcic horizon to diagnostic horizons and features based on described carbonate masses and concretions.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: 0 to 102 cm (0 to 40 in). (A1, A2, Bk1, and Bk2 horizons)
Calcic horizon: 102 to 203 cm (40 to 80 in). (Bk3 horizon)
Identifiable secondary calcium carbonate: 56 to 203 cm (22 to 80 in) (Bk1, Bk2, Bk3 horizons)
ADDITIONAL DATA: KSSL-Coryell County, Texas; User Pedon ID: 80TX099003, Lab Pedon #: 81P0099 (horizons 510-515).
TAXONOMIC VERSION: Keys to Soil Taxonomy, Twelfth Edition, 2014.
National Cooperative Soil Survey
U.S.A.