LOCATION OWENS TX+KS+OKEstablished Series
TAXONOMIC CLASS: Fine, mixed, active, thermic Typic Haplustepts
TYPICAL PEDON: Owens clay--rangeland. (Colors are for dry soil unless otherwise stated.)
A--0 to 6 inches; light olive brown (2.5Y 5/4) clay, olive brown (2.5Y 4/4) moist; weak fine and medium subangular blocky structure; very hard, very firm; common fine roots throughout; common fine vesicular and tubular pores; few coarse rounded iron concretions; strongly effervescent throughout (HCl, 1 normal); 1 percent subangular limestone gravel; moderately alkaline; gradual smooth boundary. (3 to 10 inches thick)
Bk--6 to 16 inches; brown (10YR 5/3) clay, brown (10YR 4/3) moist; moderate medium angular blocky structure; extremely hard, very firm; common fine roots throughout; common fine vesicular and tubular pores; few medium and coarse irregular masses of calcium carbonate throughout; strongly effervescent throughout (HCl, 1 normal); moderately alkaline; gradual smooth boundary. (4 to 30 inches thick)
BCk--16 to 29 inches; 40 percent yellowish brown (10YR 5/4), and 40 percent gray (5Y 5/1), and 20 percent brownish yellow (10YR 6/6) clay; weak fine and medium subangular blocky structure; very hard, very firm; common very fine and fine roots throughout; common very fine and fine continuous tubular pores; few fine calcium carbonate threads between peds; slightly effervescent throughout (HCl, 1 normal); moderately alkaline; clear smooth boundary. (0 to 24 inches thick)
Cd1--29 to 47 inches; 60 percent light yellowish brown (2.5Y 6/4) clay, and 30 percent light olive brown (2.5Y 5/3), and 10 percent brownish yellow (10YR 6/8) dense clay; massive; extremely hard, very firm; few very fine and fine roots in cracks; Fractures that roots can enter are 1 to 4 inches apart horizontally; the horizon is densic material; few coarse rounded reddish yellow (7.5YR 7/6) extremely hard nonpedogenic iron concretions throughout; noneffervescent throughout (HCl, 1 normal); slightly alkaline; gradual smooth boundary. (0 to 25 inches thick)
Cd2--47 to 80 inches; 45 percent gray (5Y 5/1) and 45 percent light yellowish brown (2.5Y 6/4) and 10 percent brownish yellow (10YR 6/8) non cemented claystone bedrock; massive; extremely hard, extremely firm; few very fine and fine roots in cracks; Fractures that roots can enter are 4 to 10 inches apart horizontally; the horizon is densic material with a densic contact at the top; few coarse rounded reddish yellow (7.5YR 7/6) extremely hard nonpedogenic iron concretions throughout; noneffervescent throughout (HCl, 1 normal); slightly alkaline.
TYPE LOCATION: Erath County, Texas; from intersection of Interstate 20 and county road in Thurber, 6.1 miles south on county road, 0.15 mile west on private road and 30 feet north in rangeland. Latitude 32 degrees 26 minutes 6 seconds N; Longitude 98 degrees 27 minutes 15 seconds W.
RANGE IN CHARACTERISTICS: The solum ranges from 14 to 30 inches thick. The soil is clayey and is slightly or moderately alkaline throughout, but some pedons are noncalcareous in the upper part. Fragments of limestone, ironstone, or sandstone cover 0 to 45 percent of the soil surface. Fragments less than 10 inches across cover 0 to 25 percent; fragments 10 to 24 inches cover 0 to 20 percent with a few fragments that are more than 48 inches across. Fragments mainly less than 10 inches across comprise 0 to 7 percent of the solum.
The A horizon has hue of 7.5YR to 5Y, value of 4 to 6, chroma of 2 to 6. Texture is clay loam, clay, silty clay, or their stony counterparts. Calcium carbonate equivalent is 5 to 15 percent.
The Bw or Bk horizon has hue of 7.5YR to 5Y, value of 4 to 6, chroma of 2 to 6. Few to common mottles in shades of brown, yellow, or red are in some pedons. It is clay, clay loam, or silty clay. Threads, films, masses, and concretions of calcium carbonate range from about 0 to 10 percent by volume. Calcium carbonate equivalent is 2 to 15 percent.
The BC or BCk horizon, when present, is from 4 to 20 inches thick. It has colors in shades of olive, brown, gray or yellow. The texture is clay, silty clay or clay loam. Calcium carbonate concretions, masses or threads typically range from few to common. Some pedons contain a few gypsum crystals. Calcium carbonate equivalent is 2 to 15 percent.
The Cd1 horizon when present with less than 50 percent of the bedding planes and rock structure of the Cd2 horizon, has colors in shades of olive, brown, gray or yellow. It is dense clay. This material is densic. Concretions, masses or films of calcium carbonates range from none to about 5 percent by volume mainly in the upper part along cleavage planes or fractures. Excavation difficulty is low to moderate. Moist bulk density is 1.70 or higher. Calcium carbonate equivalent is 0 to 10 percent.
The Cd2 layer has colors mainly in shades of olive, brown, gray or yellow. It is claystone bedrock. This material is densic with rock like structure. Fractures may be more than or less than 10 cm apart and bulk density is high enough to be root restrictive. Some pedons contain thin discontinuous strata of limestone or sandstone. It is typically noneffervescent but along cleavage planes ranges to slightly effervescent. Excavation difficulty is moderate to high and material slakes in water within 1 hours. The moist bulk density is about 1.85 to 2.35. Calcium carbonate equivalent is 0 to 5 percent.
COMPETING SERIES: These are the Vernon series in the same family. Similar soils are the Brackett, Ellis, Harpersville, Knoco, Throck, and Wellsford series. Vernon soils have hue redder than 7.5YR. Brackett soils have carbonatic mineralogy and sola less than 20 inches thick. Ellis soils have smectitic mineralogy and vertic properties. Harpersville soils do not have cambic horizons and have sola less than 14 inches thick. Knoco soils have hue redder than 7.5YR. Throck soils have vertic properties, and calcium carbonate equivalent greater than 15 percent in the subsoil. In addition, Throck soils typically have mollic colors in the surface layer. Wellsford soils are in a shallow family.
GEOGRAPHIC SETTING: Owens soils are on gently sloping to steep escarpments, plains, and convex knolls. Slopes range from about 1 to 45 percent. The soil formed in residuum from gray or olive claystone bedrock of Pennsylvanian or Permian age. Mean annual precipitation ranges from 24 to 30 inches, and mean annual temperature ranges from 63 to 65 degrees F. Frost free days range from 220 to 230 days, and elevation ranges from 1,000 to 2,350 feet. Thornthwaite annual P-E indices range from 34 to 40.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Throck and Vernon series and the Bonti, Callahan, Darnell, Harpersville, Knoco, Shatruce, Tarrant, and Truce series. Throck soils are on lower positions. Vernon soils are on positions similar to Owens soils. Bonti and Callahan soils have clayey argillic horizons and are mainly above on ridgetops. Darnell soils have loamy control sections and are above on ridgetops. Harpersville soils are on similar positions. Knoco soils have sola less than 20 inches thick, hue redder than 7.5YR, and are above on convex positions. Shatruce soils have reddish argillic horizons, and are above on bouldery hillsides. Tarrant soils have mollic epipedons, clayey-skeletal particle size control section and are above on ridgetops. Truce soils have reddish argillic horizons, sola thicker than 40 inches and are on similar positions.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is very slow. Runoff is very high.
USE AND VEGETATION: The principal use is for rangeland. Small acreage has been cultivated in the past but most cultivated areas are now abandoned and returned to rangeland. Native vegetation is mainly sideoats grama, silver bluestem, buffalograss, vine-mesquite, curlymesquite, Texas needlegrass, Arizona cottontop, hairy triden, bundleflower, engelmanndaisy, western ragweed, algerita, and lotebush. Tasajillo and mesquite have invaded in most areas.
DISTRIBUTION AND EXTENT: North-Central Prairie (MLRA 80B), and Rolling Limestone Prairie (MLRA 78D) of Texas. The Owens Series is extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Brown County, Texas; 1938.
REMARKS: Observations of these soils in sampling pits show that the solum is thicker than previously supposed, with the solum in pedons being up to 1 meter thick.
NSSL Sample Nos. S84TX-429-002, S84TX-429-003.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - 0 to 6 inches. (A horizon)
Cambic horizon - 6 to 29 inches. (Bk horizon)
Densic material - 29 to 80 inches (Cd1 and Cd2 horizons)
Densic contact - 47 inches. (top of Cd2 horizon)