LOCATION FRELSBURG TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Udic Calciusterts
TYPICAL PEDON: Frelsburg clay, on a 3 percent slope in rangeland. (Colors are for moist soil unless otherwise stated. Pedon is about midway between microknoll and microdepression).
A--0 to 8 inches; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry, moderate very fine subangular blocky and granular structure; hard, firm, sticky and plastic; many fine roots; common fine pores; slightly effervescent; slightly alkaline; clear wavy boundary. (4 to 16 inches thick)
Bw--8 to 20 inches; dark gray (10YR 4/1) clay, dark gray (10YR 5/1) dry; moderate fine and very fine subangular blocky structure; very hard, firm, sticky and plastic; common fine roots; few fine pores; few pressure faces; few vertical streaks of very dark gray (10YR 3/1) A material along cracks; few fine concretions of calcium carbonate; few fine iron-manganese concretions; strongly effervescent; slightly alkaline; gradual wavy boundary. (0 to 20 inches thick)
Bss--20 to 36 inches; dark gray (10YR 4/1) clay, gray (10YR 5/1) dry; moderate medium and coarse angular blocky structure; very hard, very firm, very sticky and very plastic; common fine roots; few vertical streaks of very dark gray (10YR 3/1) A material along cracks; many parallel slickensides spaced 2 to 4 cm apart dipping toward micro-low; few fine concretions of calcium carbonate; few fine iron-manganese concretions; strongly effervescent; moderately alkaline; gradual wavy boundary. (6 to 20 inches thick)
Bkss1--36 to 52 inches; dark gray (10YR 4/1) clay, gray (10YR 5/1) dry, moderate medium and coarse angular blocky structure; very hard, very firm, sticky and plastic; few fine roots; few vertical streaks of very dark gray (10YR 3/1) A material along cracks; many parallel grooved slickensides 0.75 to 1.5 inches apart dipping toward the micro-low; common fine and medium masses and concretions of calcium carbonate; few fine iron-manganese concretions; few fine distinct light olive brown (2.5Y 5/4) masses of iron accumulation; common medium faint grayish brown (2.5Y 5/2) iron depletions; strongly effervescent; moderately alkaline; gradual wavy boundary.
Bkss2--52 to 60 inches; grayish brown (2.5Y 5/2) clay; moderate fine and medium angular blocky structure; very hard, very firm, sticky and plastic; few fine roots; few vertical streaks of very dark gray (10YR 3/1) of A material along cracks; common parallel grooved slickensides 0.75 to 1.5 inches apart dipping toward the micro-low; common fine and medium masses and concretions of calcium carbonate; few fine iron-manganese concretions; few fine distinct light olive brown (2.5Y 5/4) masses of iron accumulation; strongly effervescent; moderately alkaline; gradual wavy boundary.
Bkss3--60 to 71 inches; grayish brown (2.5Y 5/2) clay; moderate fine and medium subangular blocky structure; very hard, very firm, sticky and plastic; very few fine roots; few vertical streaks of very dark gray (10YR 3/1) A material along cracks; common grooved slickensides dipping toward the micro-low; common fine and medium masses and few concretions of calcium carbonate; few fine iron-manganese concretions; common medium distinct light olive brown (2.5Y 5/4) masses of iron accumulation; strongly effervescent; moderately alkaline; clear wavy boundary. (combined thickness of Bkss subhorizons 24 to 55 inches)
BCkss--71 to 80 inches; light gray (2.5Y 7/2) clay; weak coarse angular blocky structure; hard, firm, sticky and plastic; very few fine roots; few vertical streaks of very dark gray (10YR 3/1) A material along cracks; few thin discontinuous dark grayish brown (2.5Y 4/2) horizontally oriented bedding planes; common slickensides with grayish brown (2.5Y 5/2) surfaces; few fine masses of calcium carbonate; few fine iron-manganese concretions; few fine distinct brownish yellow (10YR 6/6) masses of iron accumulation; strongly effervescent; moderately alkaline.
TYPE LOCATION: Lavaca County, Texas; 9 miles north of Hallettsville on U. S. Highway 77; 8 miles west on Farm Road 532; about 500 feet east of Komensky store in rangeland.
RANGE IN CHARACTERISTICS: The range includes 50 percent or more of the pedon. Colors are not included for the chimneys, or high value materials that extend to the surface on some microknolls, and the center of some microdepressions that are thicker and/or darker. These conditions makeup 5 to 25 percent of most pedons.
Solum is more than 80 inches. Texture is clay or silty clay throughout with a weighted average clay content of the 10- to 40- inch particle size control section ranges from 45 to 60 percent. This is a cyclic soil and in undisturbed areas cycles of microknolls and microdepressions are repeated at 5 to 15 foot intervals and microknolls are 4 to 12 inches higher than microdepressions. The external microrelief is typically a tiger stripe pattern on areas with a slope gradient that exceeds 3 percent. Large slickensides begin at a depth of 12 to 24 inches below the surface and extend throughout the solum. When dry, the soil has cracks up to 3 inches wide at the surface and 1/2 to 2 inch wide cracks extend to a depth greater than 20 inches. The cracks remain open for a period of 90 to 150 cumulative days in most years. Iron-manganese concretions range from none to few. Effervescence ranges from very slight to strong. The reaction is slightly alkaline or moderately alkaline. Calcium carbonate equivalent ranges from 15 to 45 percent by volume in some horizon within 40 inches of the surface.
The A horizon has hue of 10YR to 5Y, value of 2 to 5, and chroma of 1. If the color value is 2 or 3 the horizon is less than 12 inches thick. Texture is clay or silty clay. Clay content ranges from 40 to 50 percent. Reaction is slightly alkaline or moderately alkaline.
The Bw horizon, where present, has hue of 10YR to 5Y, value of 4 or 5, and chroma of 1. Redox concentrations in shades of brown or yellow range from none to few. Pressure faces range from few to common. This horizon is typically absent in part of the pedon.
The Bss or Bkss horizon has hue of 10YR to 5Y, value of 4 to 7, and chroma of 1 or 2. Redoximorphic features in shades of gray, brown, or yellow range from none in some subhorizons to many. Masses, films, threads, and/or concretions of calcium carbonate range from few to many.
The BCss or BCkss horizon, where present, has hue of 10YR to 5Y, value of 5 to 7, and chroma of 1 or 2. Redoximorphic features in shades of brown, yellow, or gray range from few to many. Fragments of shale, mudstone, or siltstone range from none to common. Discontinuous bedding planes range from none to few. Masses and/or concretions of calcium carbonate range from few to many.
COMPETING SERIES: These are the Ferris, Latium, and Medlin series. Similar soils are the Deport, and Depalt series. Ferris, Latium, and Medlin series have sola less than 80 inches thick. In addition the Ferris and Medlin soils formed in Cretaceous age materials, and Latium soils have chroma of 2 or more within 12 inches of the surface. Deport and Depalt soils do not have calcic horizons within 40 inches of the surface. In addition, Depalt soils have hue of 7.5YR or redder.
GEOGRAPHIC SETTING: Frelsburg soils are on very gently sloping to moderately sloping uplands. Slopes are dominantly 1 to 8 percent. They formed in residuum from weakly consolidated calcareous clays and marls of Tertiary Age, mainly of the Fleming and Oakville Formations. Mean annual temperature ranges from 67 to 70 degrees F., and mean annual precipitation ranges from 32 to 42 inches. Frost Free days range from 260 to 280 days, and elevation ranges from 250 to 550 feet. Thornthwaite P-E indices from 46 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Latium series and the Bleiblerville, Brenham, Carbengle, and Renish soils. Latium soils are well drained and on similar to slightly more sloping associated landscapes. Bleiblerville soils have mollic colors to a depth of more than 12 inches and are on similar but slightly smoother associated landscapes. Brenham, Carbengle, and Renish soils are on lower associated slopes. These loamy soils have a mollic epipedon.
DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is very slow. Runoff is medium on slopes of 1 to 3 percent, high on 3 to 5 percent slopes, very high on 5 to 8 percent slopes.
USE AND VEGETATION: Used mainly for rangeland. A few areas are cultivated. Most areas have been cultivated in the past to corn and annual hay crops. Native vegetation is mid and tall prairie grasses and a few scattered trees.
DISTRIBUTION AND EXTENT: Southern Blackland Prairie of Texas (MLRA 86B). The series is of large extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Washington County, Texas; 1978.
REMARKS: This soil was formerly included in the Heiden series. Classification change from Chromic Udic Haplusterts to Udic Calciusterts based on application of the 6th edition of SOIL TAXONOMY.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 8 inches. (A horizon)
Cambic horizon - 8 to 36 inches. (Bw and Bss horizons)
Calcic horizon - 36 to 60 inches. (Bkss1 and Bkss2
horizons)
Vertic and Ustic features - Clayey throughout. Large slickensides at a depth of 20 to 80 inches. Cracks that remain open 90 to 150 cumulative days in most years.
ADDITIONAL DATA: Soil was described and sampled from 30 foot long pit. NSSL: S77TX-477-5 (78PO102-78PO104). Texas Ag Exp. Station Laboratory: S83TX-285-02 (1931-1937) type location pedon.
SOIL INTERPRETATION RECORD NUMBER: TX0804