LOCATION EDGE TX

Established Series
Rev. LCB-CJV-RM
05/2014

EDGE SERIES

The Edge series consists of deep, well drained soils that formed in loamy and clayey residuum derived from Eocene age, stratified, sandstone and mudstone. These nearly level to strongly sloping soils are on side slopes and interfluves on upland ridges. Slopes range from 1 to 12 percent. Mean annual precipitation is about 965 mm (38 in) and the mean annual air temperature is 19 degrees C (66 degrees F).

TAXONOMIC CLASS: Fine, mixed, active, thermic Udic Paleustalfs

TYPICAL PEDON: Edge fine sandy loam, 3 percent slope, in rangeland. (Colors are for moist soil unless otherwise stated).

A--0 to 20 cm (0 to 8 in); brown (10YR 4/3) fine sandy loam, pale brown (10YR 6/3) dry; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common medium roots and common fine roots; few medium and few fine pores; 1 percent 2 to 76 mm (0.75 to 30in) ironstone nodules; moderately acid; clear smooth boundary. (Thickness is 8 to 23 cm [3 to 9 in])

E--20 to 28 cm (8 to 11 in); brown (10YR 5/3) fine sandy loam, very pale brown (10YR 7/3) dry; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common medium roots and common fine roots; few medium and few fine pores; 1 percent 2 to 76 mm (0.75 to 30in) ironstone nodules; few fine fragments of red Bt material; slightly acid; abrupt smooth boundary. (Thickness is 0 to 25 cm [0 to 10 in])

Bt1--28 to 48 cm (11 to 19 in); dark red (2.5YR 3/6) clay, red (2.5YR 4/6) dry; moderate medium angular blocky structure parting to moderate fine angular blocky; extremely hard, firm, very sticky and very plastic; few very fine roots and few fine roots; few fine pores; 25 percent distinct clay films on all faces of peds; 1 percent fine distinct pale brown (10YR 6/3), moist, iron depletions; very strongly acid; gradual smooth boundary.

Bt2--48 to 74 cm (19 to 29 in); red (2.5YR 4/6) clay; red (2.5YR 5/6) dry; weak medium and coarse prismatic structure parting to moderate fine angular blocky; extremely hard, firm, sticky and plastic; few very fine roots and few fine roots; few fine pores; 25 percent distinct clay films on all faces of peds; 1 percent fine distinct yellowish brown (10YR 5/4), moist, iron-manganese masses and 10 percent medium distinct pale brown (10YR 6/3), moist, iron depletions; very strongly acid; gradual smooth boundary.

Bt3--74 to 94 cm (29 to 37 in); red (2.5YR 4/6) clay loam, red (2.5YR 5/6) dry; weak medium and coarse prismatic structure parting to moderate fine angular blocky; very hard, firm, sticky and plastic; few very fine roots and few fine roots; few fine pores; 5 percent very dark gray (10YR 3/1), moist, organic stains on surfaces along root channels and 25 percent distinct reddish brown (5YR 5/4), moist, clay films on all faces of peds; 10 percent fine distinct light yellowish brown (10YR 6/4), moist, masses of oxidized iron and 10 percent fine distinct brown (10YR 5/3), moist, iron depletions; very strongly acid; gradual smooth boundary.

Bt4--94 to 109 cm (37 to 43 in); yellowish red (5YR 5/6) clay loam; yellowish red (5YR 4/6) dry; weak medium prismatic structure parting to moderate fine subangular blocky; very hard, firm, sticky and plastic; few very fine roots and few fine roots; few medium pores; 5 percent very dark gray (10YR 3/1), moist, organic stains on surfaces along root channels and 25 percent distinct brown (7.5YR 4/4), moist, clay films on vertical faces of peds; 1 percent fine distinct yellowish brown (10YR 5/4), moist, iron-manganese masses; slightly acid; gradual smooth boundary. (Combined thickness of the Bt horizons is 36 to 150 cm [8 to 59 in])

BCt--109 to 122 cm (43 to 48 in); strong brown (7.5YR 5/6) sandy clay loam; reddish yellow (5YR 6/6) dry; weak very coarse prismatic structure parting to weak coarse subangular blocky; very hard, firm, sticky and plastic; few very fine roots and few fine roots; 25 percent distinct brown (7.5YR 4/4), moist, clay films on vertical faces of peds; 1 percent fine distinct light brownish gray (10YR 6/2), moist, iron depletions and 1 percent fine distinct light brownish gray (10YR 6/2), moist, iron depletions along lamina or strata surfaces; neutral; gradual smooth boundary. (Thickness of the BCt horizon is 0 to 46 cm [0 to 18 in])

C/Bt--122 to 147 cm (48 to 58 in); strong brown (7.5YR 5/6) weakly consolidated siltstone that has a loam texture; few medium distinct red (2.5YR 5/6) mottles; weak very coarse prismatic structure; very hard, friable, slightly sticky and slightly plastic; few very fine roots; 5 percent distinct brown (7.5YR 5/4), moist, clay films on vertical faces of peds; 1 percent medium distinct red (2.5YR 5/6), moist, masses of oxidized iron; 1 percent medium barite masses; horizon becomes stratified with depth in colors of strong brown (7.5YR 5/6), yellowish brown (10YR 5/6) and thin discontinuous gray (5YR 6/1) seams of shale; slightly alkaline; gradual smooth boundary.

C/B--147 to 171 cm (58 to 75 in); light yellowish brown (10YR 6/4) weakly consolidated siltstone that has a loam texture; massive; very hard, friable, slightly sticky and slightly plastic; few very fine roots; 1 percent fine distinct strong brown (7.5YR 5/6), moist, masses of oxidized iron along lamina or strata surfaces;; slightly alkaline; gradual smooth boundary. (Combined thickness is 0 to 91 cm thick [0 to 36 in])

C--171 to 203 cm (75 to 80 in); light brownish gray (10YR 6/2) weakly consolidated siltstone that has a silt loam texture; very hard, friable; slightly alkaline.

TYPE LOCATION: Milam County, Texas; from the intersection of U. S. Highway 79 and Texas Highway 36 in Milano; 2.5 miles west on Highway 36 to county road; 1.0 miles northeast on county road; 75 ft east of road in an old field being used for rangeland. Latitude 30 degrees, 44 minutes, 36 seconds N, Longitude 96 degrees 53 minutes 17 seconds W.

RANGE IN CHARACTERISTICS:

Depth of solum: 100 to 150 cm (40 to 60 in), Deep
Depth of abrupt texture change: 18 to 84 cm (7 to 33 in)
Depth of argillic horizon: 13 to 84 cm (5 to 33 in)
Depth to secondary carbonates: Greater than 75 cm (30 in)
Redoximorphic features: Masses and concentrations of oxidized iron and iron depletions from 0 to 188 cm (0 to 74 in)
Soil moisture: Dry in some or all parts of the soil moisture control section for more than 90 or more cumulative days and moist in some parts either for more than 180 cumulative days per year or for 90 or more consecutive days in normal years. Ustic soil moisture regime

Particle-size control section (weighted average):
Clay Content: 35 to 55 percent
Coefficient of Linear Extensibility (COLE): 0.06 to 0.09 in upper part
Shrink Swell: The upper part of the argillic has high shrink-swell potential. The lower part has moderate to low shrink-swell potential.
Base saturation: 45 to 90 percent
Linear Extensibility (LE): Less than 6.0 between the soil surface and a depth of 100 cm (40 in).

A or Ap horizon(s)
Hue: 7.5YR or 10YR dry or moist
Value: 4 to 6 dry or moist
Chroma: 2 to 4 dry or moist
Texture: Sandy loam, fine sandy loam, gravelly fine sandy loam, very fine sandy loam, loam
Rock fragments: 0 to 35 percent ironstone nodules
Reaction: very strongly acid to neutral

E horizon
Hue: 7.5YR or 10YR dry or moist
Value: 5 to 7 dry or moist
Chroma: 2 to 4 dry or moist
Texture: Loamy fine sand, fine sandy loam, very fine sandy loam, loam, sandy clay loam
Rock fragments: 0 to 10 percent ironstone nodules
Reaction: very strongly acid to slightly acid

Bt or Btss horizon(s) - Upper part
Hue: 2.5YR or 5YR dry or moist
Value: 3 to 6 dry or moist
Chroma: 4 to 8 dry or moist
Texture: Sandy clay loam, clay loam, sandy clay, clay
Redox concentrations: amount-0 to 10 percent, size-fine to medium, contrast-distinct, boundary-clear, shade-light yellowish brown and red
Redox depletions: amount-0 to 10 percent, size-fine, contrast-distinct, boundary-clear, shade-brown and pale brown
Iron-manganese concentrations: amount-0 to 1 percent, size-fine, contrast-distinct, boundary-clear, shade-yellowish brown
Slickensides: Where present, are discontinuous and Btss horizons do not exceed 15 cm (6 in) in thickness
Rock fragments: 0 to 10 percent ironstone nodules, shale and/or sandstone
Reaction: Very strongly acid to slightly acid

Bt horizon(s) - Lower part
Hue: 2.5YR or 5YR dry or moist
Value: 3 to 5 dry or moist
Chroma: 4 to 8 dry or moist
Texture: Clay loam, sandy clay, clay
Redox concentrations: amount-0 to 10 percent, size-fine to medium, contrast-distinct, boundary-clear, shade-light yellowish brown and red
Redox depletions: amount-0 to 10 percent, size-fine, contrast-distinct, boundary-clear, shade-brown and pale brown
Iron-manganese concentrations: amount-0 to 1 percent, size-fine, contrast-distinct, boundary-clear, shade-yellowish brown
Rock fragments: 0 to 10 percent ironstone nodules, shale and/or sandstone
Reaction: Very strongly acid to neutral

BCt or BC horizon
Hue: 2.5YR to 10YR dry or moist
Value: 4 or 8 dry or moist
Chroma: 2 to 8 dry or moist
Texture: Fine sandy loam, sandy clay loam, clay loam, clay
Additional texture features: Some horizons are stratified with clayey or sandy materials
Redox depletions: amount-0 to 10 percent, size-fine, contrast-distinct, boundary-clear, shade-brown and pale brown
Rock fragments: 0 to 15 percent ironstone nodules, grayish, shale and/or sandstone
Reaction: very strongly acid to slightly alkaline

C/B, C/Bt and C horizon(s)
Hue: 5YR to 2.5Y dry or moist
Value: 4 to 8 dry or moist
Chroma: 1 to 8 dry or moist
Texture: Sandy loam, fine sandy loam, sandy clay loam, silt loam, loam, clay loam, sandy clay, clay
Additional texture features: Some horizons are stratified with weathered mudstone. Some pedons contain sandy strata.
Redox concentrations: amount-0 to 10 percent, size-fine to medium, contrast-distinct, boundary-clear, shade-light yellowish brown and red
Rock fragments: 0 to 15 percent ironstone nodules, shale and/or sandstone
Additional horizon features: Some pedons contain few fine or very fine Barite masses
Reaction: strongly acid to moderately alkaline

COMPETING SERIES: These are the Callisburg (TX), Chigley (OK), Cona (TX), Minwells (TX), Shiro (TX), Truce (TX), and Windthorst (TX) series in the same family. Similar soils are the Axtell, Gredge, and Rosanky series.

Axtell soils: have vertic properties and solum depth greater than 150 cm (60 in)
Callisburg soils: solum thickness greater than 150 cm (60 in)
Chigley soils: lithic contact with conglomerate below 150 cm (60 in)
Cona soils: solum thickness of 50 to 100 cm (20 to 40 in) Minwells soils: formed in old alluvial deposits and are underlain by beds of gravel.
Gredge soils: have smectitic mineralogy and solum depth greater than 150 cm (60 in)
Rosanky soils: members of the Ultic subgroup, and do not have redoximorphic features in the upper part of the argillic horizon
Shiro soils: solum thickness of 50 to 100 cm (20 to 40 in)
Truce soils: underlain by shale
Windthorst soils: have low shrink swell properties in the upper horizon and are in a dryer climate

GEOGRAPHIC SETTING:
Parent Material: Loamy and clayey residuum of Eocene age derived from sandstone and mudstone of the Wilcox Group
Landscapes: Inland-dissected coastal plains
Landforms: Side slopes and interfluves on ridges
Slope: 1 to 12 percent
Mean Annual Air Temperature: 17.8 to 20.4 degrees C (64 to 69 degrees F)
Mean Annual Precipitation: 813 to 1143 mm (32 to 45 in)
Frost Free Days: 240 to 270 days
Elevation: 66 to 187 m (215 to 614 ft)
Thornthwaite P-E: 52 to 64

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Axtell, Crockett, Gasil, Gredge, Lufkin, Rosanky, and Silawa series.

Axtell soils: typically on lower terrace positions.
Crockett soils: have a clayey argillic horizon with vertic properties
Gasil and Silawa soils: have fine-loamy control sections and Gasil soils are on similar stream divide positions
Gredge, Rosanky and Crockett soils: on positions similar to the Edge series.
Lufkin soils: on lower flats or depressions and have grayish colors throughout
Silawa soils: on slightly lower terrace positions

DRAINAGE AND PERMEABILITY: Well drained. Permeability is very slow. Runoff is high on less than 1 percent slopes and very high from 1 to 12 percent slopes.

USE AND VEGETATION: The major uses are rangeland or improved pasture with a few cultivated areas. The native plant community is a savannah with scattered post oak, blackjack oak, and elm trees with ground cover of medium and tall native grasses. Present vegetation is a fairly dense cover of oak trees, yaupon, American beautyberry and hawthorn with shade tolerant grasses such as longleaf uniola. Many areas have been cultivated in the past. These old cropland fields are being used for rangeland or have been established to bermudagrass, bahiagrass or other improved pasture grasses. A few small areas have been planted to loblolly pine. Old fields being used for rangeland are typically producing low quality perennial grasses, annuals grasses, forbs and some fields are being invaded by mesquite.

DISTRIBUTION AND EXTENT: Land Resource Region J - Southwestern Prairies Cotton and Forage Region. East Central Texas. Texas Claypan Area, Southern Part (MLRA 87A). This soil is of large extent.

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

SERIES ESTABLISHED: Freestone County, Texas; 1986. The Edge series was originally established in Brazos County, Texas in 1955. In May, 1963 the series was placed on the inactive list and the soils were included with the similar Axtell series. The Axtell soils are members of a fine, smectitic, thermic family of Udertic Paleustalfs. Axtell soils are typically on terraces or in valley fill positions and have a solum thicker than 152 cm (60 in)and with vertic properties. The re-defined Edge series has a concept similar to the original series established in Brazos County.

REMARKS: This pedon is within an area of Edge fine sandy loam, eroded. It is on a small area that is not eroded. These soils are not saturated in any part of the solum for more than 30 consecutive days during most years.

Diagnostic horizons and features recognized in this pedon:

Ochric epipedon: 0 to 28 cm (0 to 11 in). (A horizon)
Albic materials: 20 to 28 cm (8 to 11 in). (E horizon)
Albic horizon: 20 to 28 cm (8 to 11 in). (E horizon)
Argillic horizon: 28 to 122 cm (11 to 48 in). (Bt and BCt horizons)
Abrupt textural change: At the upper boundary of the Bt horizon.
Redox concentrations: 48 to 191 cm (19 to 75 in). (Bt, BCt, and C/B horizons)
Redox depletions with chroma 2 or less: 109 to 122 cm (43 to 48 in). (Bt, BCt, and C/B horizons)

ADDITIONAL DATA:
KSSL Data: Milam County, S83TX-331-1 (832755-832761), TAMU Data: Bastrop County, S82TX-021-1-4, 84TX-021-1-5; Freestone County, S84TX-161-1-2, S84TX-161-2- 2; Milam County, S84TX-331-8-2, S84TX-331-9-2, S84TX-331-10- 2, S86TX-331-01-10; Lee County, S81TX-287-2 (1198-1207).

Taxonomic version: Keys to Soil Taxonomy, Eleventh Edition, 2010.

National Cooperative Soil Survey
U.S.A.