LOCATION CAMPBELLTON             TX

Established Series
Rev. WJG-CNL-CKH
11/2010

CAMPBELLTON SERIES

The Campbellton series consist of soils that are very deep, well drained, moderately slowly permeable soils, derived from calcareous clayey or loamy residuum weathered from sandstone and claystone like those of the Whitsett Formation of Oligocene age. These soils are on side slopes or shoulders of interfluves. Slopes range from 0 to 5 percent. Mean annual precipitation is about 559 mm (22in) and the mean annual air temperature is about 22 degrees C (72 degrees F).

TAXONOMIC CLASS: Fine, smectitic, hyperthermic Typic Argiustolls

TYPICAL PEDON: Campbellton loam, in rangeland; elevation is 87 meters (285feet). (Colors are for dry soil unless otherwise stated.)

A1--0 to 15 cm (0 to 6 in); dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; hard, friable; common fine roots; few fine pores; slightly effervescent; 7 percent calcium carbonate equivalent; moderately alkaline; clear smooth boundary.

A2--15 to 30 cm (6 to 12 in); dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate medium subangular blocky structure; hard, friable; common fine roots; few fine pores; few fine concretions of calcium carbonate; strongly effervescent; 11 percent calcium carbonate equivalent; moderately alkaline; gradual wavy boundary. (thickness of the combined A horizons ranges from 20 to 47 cm [8 to 18 in])

Btk1--30 to 43 cm (12 to 17 in); grayish brown (10YR 5/2) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; very hard, firm; few fine roots; few fine pores; few fine concretions and few threads of calcium carbonate; strongly effervescent; 12 percent calcium carbonate equivalent; moderately alkaline; gradual wavy boundary.

Btk2--43 to 64 cm (17 to 25 in); light gray (10YR 7/2) clay, light brownish gray (10YR 6/2) moist; moderate fine and medium angular blocky structure; very hard, very firm; few fine roots; few fine pores; few distinct clay films on surface of peds; few krotovinas; few fine concretions and few threads of calcium carbonate; 14 percent calcium carbonate equivalent; strongly effervescent; moderately alkaline; gradual wavy boundary. (thickness of the combined Btk horizons ranges from 25 to 48 cm [10 to 19 in])

Btkz--64 to 89 cm (25 to 35 in); light gray (10YR 7/2) clay, light brownish gray (10YR 6/2) moist; weak and moderate fine and medium angular blocky structure; very hard, very firm; few fine roots; few fine pores and old root channels; few distinct clay films on surface of peds; few fine concretions and threads of calcium carbonate; few films and threads of neutral salts; 16 percent calcium carbonate equivalent; strongly effervescent; moderately alkaline; gradual wavy boundary. (thickness of the Btkz horizon ranges from 15 to 36 cm [6 to 14 in])

BCkz--89 to 119 cm (35 to 47 in); light gray (10YR 7/2) clay, light brownish gray (10YR 6/2) moist; weak fine and medium subangular blocky structure; very hard, very firm; few fine roots; few fine pores; few distinct clay films on surface of peds; few old root channels filled with decaying root residue; few concretions and threads of calcium carbonate; few films and threads of neutral salts; 18 percent calcium carbonate equivalent; strongly effervescent; moderately alkaline; gradual wavy boundary. (thickness of the BCkz horizon ranges from 15 to 36 cm [6 to 14 in])

Ckz1--119 to 165 cm (47 to 65 in); very pale brown (10YR 8/2) clay loam, light gray (10YR 7/2) moist; massive; hard, friable; common fine pores; few very fine black particles that appear to be igneous material; contains about 5 percent by volume of calcium carbonate as concretions, masses and threads; few films and threads of neutral salts; 19 percent calcium carbonate equivalent; strongly effervescent; moderately alkaline; gradual wavy boundary. (thickness of Ckz horizon ranges from 20 to 51 cm [8 to 20 in])

Ckz2--165 to 203 cm (65 to 80 in); pale yellow (2.5Y 8/2) loam, light gray (2.5Y 7/2) moist; massive; slightly hard, very friable; contains about 2 or 3 percent by volume of calcium carbonate mainly as masses; few films and threads of neutral salts; few very fine black particles that appear to be igneous material; strongly effervescent; 13 percent calcium carbonate equivalent; moderately alkaline.

TYPE LOCATION: Atascosa County, Texas; 6.6 miles southwest of Campbellton on Farm Road 791 to 7-4 Ranch entrance; 200 feet south and 200 feet east in rangeland. Whitsett SW, USGS topographic quadrangle; Latitude: 28 degrees, 41 minutes, 0.13 seconds N; Longitude: 98 degrees, 22 minutes, 29.89 seconds W.; NAD 83.

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: 23 degrees C (74 degrees F)
Depth to argillic: 8 to 113 cm (3 to 45 in)
Depth to secondary carbonates: 25 to 203 cm (10 to 80 in)
Particle-size control section (weighted average)
Calcium carbonate equivalent: 10 to 25 percent

A horizon
Hue: 10YR
Value: 3 to 5
Chroma: 1 to 3
Texture: loam, sandy clay loam or clay loam
Clay content: 25 to 40
EC: 0 to 2 dS/m
Reaction: slightly alkaline or moderately alkaline


Bt or Btk horizon
Hue: 10YR or 2.5Y
Value: 3 to 5
Chroma: 1 to 4
Texture: clay or clay loam
Clay content: 35 to 48
Identifiable secondary carbonates: 1 to 5 percent, fine, threadlike and masses in the matrix
EC: 2 to 8 dS/m
SAR: 2 to 15
Reaction: slightly alkaline or moderately alkaline

Btkz horizon
Hue: 10YR or 2.5Y
Value 5 to 7
Chroma 2 to 4
Texture: clay or clay loam
Clay content: 35 to 55
Identifiable secondary carbonates: 1 to 10 percent, fine and medium, threadlike and masses in the matrix
SAR: 8 to 40
Reaction: slightly alkaline or moderately alkaline

BC horizon (where present)
Hue: 7.5YR, 10YR, or 2.5Y
Value: 6 to 8
Chroma: 2 to 6
Texture: clay loam or clay
Clay content: 32 to 50
EC: 4 to 8 dS/m
SAR: 15 to 45
Reaction: slightly alkaline or moderately alkaline

Ckyz horizon
Hue: 10YR or 5Y
Value: 6 to 8
Chroma: 2 to 4
Texture: clay or clay loam interbedded with claystone and sandstone
Gypsum: 0 to 5 percent
Reaction: slightly alkaline or moderately alkaline

Cdz or Cdyz (where present)
Hue: 2.5Y or 5Y
Value: 5 to 8
Chroma: 1 to 5
Texture: clay, clay loam or silty clay
Gypsum: 0 to 5 percent
Reaction: slightly alkaline or moderately alkaline

The parent material has few fine black particles that appear to be igneous material.

COMPETING SERIES: There are no competing series in this family. Similar soils include the Coy (TX), Elmendorf (TX), Luckenbach (TX), Pernitas (TX), Runge (TX), Weesatche (TX), and Zavco (TX) series.

Coy and Elmendorf: have vertic properties
Luckenbach soils: have mean annual soil temperatures less than 22 degrees C (72 degrees F).
Pernitas, Runge, Weesatche soils: have less than 35 percent clay in the upper 50 cm (20 in) of the Bt horizon
Zavco soils: are dry in the moisture control section for longer periods

GEOGRAPHIC SETTING:
Parent material: calcareous clayey or loamy sediments interbedded with shale derived from the Whitsett Formation
Landscape: inland, dissected coastal plain
Landform: side slopes or shoulders of interfluves
Slope: 0 to 5 percent
Mean annual temperature: 21 to 23 (70 to 74 degrees F)
Mean annual precipitation: 584 to 762 mm (23 to 30 in)
Frost-free period: 260 to 290 days
Elevation: 61 to 137 m (200 to 450 ft)
Thornthwaite P-E indices: 28 to 40

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Coy (TX), Elmendorf (TX), Fashing (TX), Laparita (TX), Monteola (TX), Schattel (TX), and Weigang (TX) series.
Coy, Fashing, Laparita, and Monteola soils: have vertic properties. Coy, Elmendorf, Laparita, and Monteola soils occur on a lower landscape position. Fashing and Weigang soils: occur on similar or a slightly higher landscape position; have sola less than 51 cm (20 in) thick.
Schattel soils: have a ochric epipedon; are on a similar landscape position.

DRAINAGE AND PERMEABILITY: Well drained. Moderately slow permeability. Runoff is low on 0 to 1 percent slopes and medium on 1 to 5 percent slopes.

USE AND VEGETATION: Used mostly for rangeland. Scattered areas are cultivated mainly to grain sorghum, small grain, and introduced grasses. Grasses are mainly pink pappusgrass, bristlegrass, twoflower trichloris, fall witchgrass, Hall panicum, red grama, and threeawn. Woody plants are mesquite, blackbrush, whitebrush, tasajillo, lotebush condalia, guayacan, and pricklypear.

DISTRIBUTION AND EXTENT: Northern Rio Grande Plain, Texas; LRR I; MLRA 83A; moderate extent.

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

SERIES ESTABLISHED: Atascosa County, Texas; 1977.

REMARKS:

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 30 cm (0 to 12 in). (A1 and A2 horizons)

Argillic horizon: 30 to 89 cm (12 to 35 in). (Btk1, Btk2 and Btkz horizons)

ADDITIONAL DATA: Particle-size analysis, salinity and sodicity test were performed at the project office on pedons S09TX3114014, S09TX3114015, S09TX3114034, S10TX3112562, and P10TX3114726.

TAXONOMIC VERSION: Keys to Soil Taxonomy, Eleventh Edition, 2010.

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National Cooperative Soil Survey
U.S.A.