LOCATION ROETEX TXEstablished Series
TAXONOMIC CLASS: Very-fine, mixed, active, thermic Aquic Hapluderts
TYPICAL PEDON: Roetex clay--pasture. (Colors are for moist soil unless otherwise stated.)
A1--0 to 8 inches; dark reddish brown (5YR 3/2) clay; weak coarse prismatic structure parting to moderate medium angular blocky; very firm, extremely hard; common fine roots; very slightly effervescent; slightly alkaline; abrupt wavy boundary.
A2--8 to 15 inches; dark reddish brown (5YR 2.5/2) clay; weak coarse prismatic structure parting to moderate medium angular blocky; very firm, extremely hard; common fine roots; slightly effervescent, slightly alkaline; clear wavy boundary. (combined A horizons 8 to 18 inches thick)
Bw--15 to 21 inches; dark reddish brown (5YR 3/4) clay; common medium prominent dark gray (10YR 4/1) redox depletions; weak coarse prismatic structure parting to moderate medium angular blocky; very firm, extremely hard; few fine roots; few pressure faces and small slickensides; few vertical streaks of very dark gray (5YR 3/1) clay about 1/4 ot 1/2 inch wide and 3 to 6 inches long; strongly effervescent; moderately alkaline; clear wavy boundary. (4 to 12 inches thick)
Bss1--21 to 26 inches; reddish brown (5YR 4/3) clay; common fine prominent gray (10YR 5/1) and common fine faint dark reddish brown (5YR 3/4) redoximorphic features; weak coarse prismatic structure parting to moderate medium angular blocky; very firm, extremely hard, few fine roots; common intersecting slickensides; strongly effervescent; moderately alkaline; gradual wavy boundary.
Bss2--26 to 36 inches; dark reddish brown (5YR 3/4) clay; common fine prominent gray (5YR 5/1) redox depletions; moderate medium angular blocky structure; very firm, extremely hard, few fine roots; many large intersecting slickensides tilted 40 to 60 degrees; strongly effervescent; moderately alkaline; gradual wavy boundary.
Bss3--36 to 53 inches; dark reddish brown (5YR 3/4) clay; common discontinuous strata 1 to 2 inches thick of reddish brown (5YR 4/3) and gray (5YR 5/1) clay; moderate medium and coarse angular blocky structure; very firm, extremely hard, few fine roots; many large intersecting slickensides tilted 40 to 60 degrees; few fine concretions of calcium carbonate; strongly effervescent; moderately alkaline; gradual wavy boundary. (combined Bss horizons 28 to 48 inches thick)
BCss1--53 to 61 inches; reddish brown (5YR 4/4) clay; some ped surfaces are gray (5YR 5/1); weak medium and coarse angular blocky structure; very firm, extremely hard, few fine roots; common intersecting slickensides; few fine concretions of calcium carbonate; strongly effervescence; moderately alkaline; gradual wavy boundary.
BCss2--61 to 72 inches; reddish brown (5YR 4/4) clay; some ped surfaces are dark gray (5YR 4/1); weak medium and coarse angular blocky structure; very firm, extremely hard; few fine roots; common intersecting slickensides; few fine concretions of calcium carbonate; strongly effervescent; moderately alkaline; abrupt wavy boundary. (combined BCss horizons 0 to 32 inches thick)
C--72 to 80 inches; stratified layers of yellowish red (5YR 4/6) and gray (2.5YR N5/) silty clay; massive; very firm, extremely hard; few fine concretions of calcium carbonate; strongly effervescent; moderately alkaline.
TYPE LOCATION: Burleson County, Texas; from the intersection of Texas Highway 36 and Farm Road 166 in Caldwell, Texas, 12.5 miles east on Farm Road 166; 1500 feet north in native pasture.
RANGE IN CHARACTERISTICS: The solum is 60 to more than 80 inches thick. The clay content of the control section ranges from 60 to 72 percent. This is a cyclic soil and undisturbed areas have gilgai microrelief with microknolls a few inches higher than microdepressions. The amplitude of waviness between mollic colored materials in the upper part of the solum and the higher value colors in the lower part ranges from 6 to 18 inches. Slickensides range from few to many. They begin at a depth of 12 to 24 inches in most pedons and extend throughout the solum. The soil cracks when dry. However, cracks remain open for less than 90 cumulative days during most years. Iron manganese concretions and masses range fron none to about 3 percent by volume throughout. Reaction is slightly alkaline or moderately alkaline and it ranges from very slightly to strongly effervescent. Some pedons have buried A horizons in the control section.
The A horizon has hue of 2.5YR to 10YR, value of 3 or 4, and chroma of 2 or 3. Texture is clay or silty clay. Most pedons have a few pressure faces or small slickensides in the lower part.
The Bw horizon has colors in shades of red, brown, or gray in hue of 2.5YR, 5YR or 7.5YR, value of 3 to 5, and chroma of 2 to 6. Redox depletions with chroma of 2 or less range from few to common. Or, the matrix has chroma of 2 or 3 with distinct redox concentrations in shades of red, yellow, or brown.
The Bss horizon has colors in shades of red or brown in hue of 2.5YR, 5YR or 7.5YR, value of 3 to 5, and chroma of 2 to 6. Some pedons have redoximorphic features in these colors or in shades of gray. Intersecting slickensides range from common to many.
The C horizon has colors in shades red brown or yellow. Texture is silty clay or clay with strata of loamy materials or it is stratfied with loamy and clayey layers.
COMPETING SERIES: There are no competing series. Similar soils are the Brooksville, Roebuck, Ships, Terouge, Texark, and Zilaboy series. The Brooksville, Roebuck Terouge, and Zilaboy soils have a fine particle-size family and smectitic mineralogy. Ships soils do not have redox depletions in the upper 20 inches of the pedon. Texark soils have smectitic mineralogy, and have chroma of 1 in the A horizon.
GEOGRAPHIC SETTING: Roetex soils are on flood plains, primarily in slackwater areas, depressions, in swales or old channels. Unless protected, they flood from several times a year to once in 2 years. Surfaces are level to slightly concave, and slope gradients are mainly less than 1 percent. The Roetex soils are formed in clayey alluvium along streams carrying sediments from Permian red beds mainly the Brazos and Colorado Rivers. The climate is moist subhumid. The mean annual precipitation ranges from 32 to 40 inches, and the mean annual temperature ranges from 66 to 70 degrees F. Frost-free days range from 260 to 280 days and elevation ranges from 200 to 350 feet. Thornthwaite P-E indices range from 54 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Ships series and the Highbank and Weswood series. Highbank soils have loamy surface layers and fine particle-size control sections. Weswood soils have coarse-silty control sections. Associated soils are on slightly higher positions within the flood plain.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Permeability is very slow. Runoff is low. After flooding water is ponded for very brief to very long periods. Flooding and wetness is mainly during rainy periods between October and May.
USE AND VEGETATION: The soil is used mainly by wildlife. A few areas are managed and leased for duck hunting. However, some areas are used for pasture. Native vegetation includes an understory of Virginia wildrye, eastern gamagrass, switchgrass, panicums, and paspalums with an open to thick stand of black willow, elm, oak, ash, bois d'arc, hackberry, or pecan. Some areas have been drained for cultivation, but crop yields are limited or the crop is lost because of flooding and wetness.
DISTRIBUTION AND EXTENT: East Central Texas along the Brazos and Colorado Rivers. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Falls County, Texas; 1975.
REMARKS: This soil has been changed from a fine to a very- fine particle-size family and from a vertic subgroup to a vertisol (5/91). These decisions are based on lab. data and a field study of the series which included describing this soil in a large backhoe pit. Classification changed from Aquic Chromuderts to Aquic Hapluderts (5/93) based on new classification for Vertisols. Data from this site location indicates it is borderline montmorillonitic/mixed clay mineralogy. However, data from other soils on this gemorphic surface indicates mixed/montmorillonitic mineralogy.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 15 inches. (A1 and A2 horizons)
Cambic Horizon - 15 to 72 inches. (Bss and BC horizons)
Aquic conditions - evidenced by redoximorphic features below 15 inches.
Vertisol- Common intersecting slickensides, and clayey throughout.
Uderts- Cracks that open and close and remain open for less than 90 cumulative days during most years.
ADDITIONAL DATA: LSL# 74L355 - 74L359; S89TX-051-001 - TAMU Lab Nos. 3870-3878