LOCATION NUVALDE TXEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, thermic Typic Calciustolls
TYPICAL PEDON: Nuvalde clay loam--cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; grayish brown (10YR 5/2) clay loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, friable, sticky; many fine roots; strongly effervescent; moderately alkaline; abrupt smooth boundary. (4 to 10 inches thick)
A--6 to 13 inches; dark grayish brown (10YR 4/2) clay loam, very dark grayish brown (10YR 3/2) moist; moderate very fine subangular blocky structure; hard, firm, sticky; many fine roots; few fine pores; violently effervescent; moderately alkaline; gradual smooth boundary. (6 to 16 inches thick)
Bw--13 to 21 inches; brown (10YR 5/3) clay, dark brown (10YR 4/3) moist; moderate very fine subangular blocky structure; hard, firm, sticky; few fine roots; few fine pores; violently effervescent; moderately alkaline; gradual wavy boundary. (4 to 18 inches thick)
Bk1--21 to 32 inches; light brown (7.5YR 6/4) clay, brown (7.5YR 5/4) moist; moderate very fine subangular blocky structure; hard, firm, sticky; few fine roots; few fine pores; few fine masses; few medium concretions, few films and threads of calcium carbonate; 20 percent calcium carbonate equivalent; violently effervescent; moderately alkaline; gradual wavy boundary. (6 to 26 inches thick)
Bk2--32 to 63 inches; pink (7.5YR 7/4) silty clay loam, light brown (7.5YR 6/4) moist; weak medium subangular blocky structure; hard, friable, sticky; 30 percent pinkish white weakly and strongly cemented concretions of calcium carbonate that are 1 to 15 mm in diameter; few fine masses of calcium carbonate; 70 percent calcium carbonate equivalent; violently effervescent; moderately alkaline; diffuse wavy boundary. (6 to 40 inches thick)
BCk--63 to 84 inches; pink (7.5YR 8/4) silty clay loam, pink (7.5YR 7/4) moist; massive; hard, friable, slightly sticky; few medium weakly and strongly cemented concretions and fine soft masses of calcium carbonate; 50 percent calcium carbonate equivalent; violently effervescent; moderately alkaline.
TYPE LOCATION: McCulloch County, Texas; 1.3 miles southwest of Rochelle via U.S. Highway 190; 0.9 mile south on county road; 0.1 mile west and 150 yards south in field.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to 80 inches. The weighted average of the total clay content of the 10- to 40- inch control section ranges from 30 to 50 percent, with silicate clay content ranging from 25 to 35 percent. Calcium carbonate equivalent ranges from 10 to 65 percent throughout. However, the control section averages less than 40 percent.
The A horizon has hue of 7.5YR or 10YR, value of 4 or 5, and chroma of 2 or 3. Texture is clay loam, silty clay loam, or silty clay.
The Bw horizon has hue of 7.5YR or 10YR, value of 4 or 6, and chroma of 2 to 4. Texture is clay loam, silty clay loam, clay or silty clay with total clay content ranging from 35 to 50 percent. Calcium carbonate equivalent ranges from 15 to 25 percent.
The Bk1 horizon has hue of 7.5YR or 10YR, value of 5 to 7, and chroma of 3 or 4. Texture is clay loam, silty clay loam, clay, or silty clay. Below 40 inches the Bk horizon textures are silt loam or loam. The amount of visible carbonates in the form of masses, concretions and films and threads ranges from less than 1 percent by volume in the upper part to as much as 30 percent in the lower part. Calcium carbonate equivalent ranges from 30 to 65 percent. Structure ranges from weak to moderate very fine to medium subangular blocky.
The Bk2 horizon has hue of 7.5YR or 10YR, value of 4 to 7 and chroma of 3 or 6. Texture is loam, silty clay loam, clay loam, averaging 24 to 40 percent clay, of which 24 to 35 percent is silicate clay. Calcium carbonate equivalent ranges from 30 to 65 percent.
The BCk horizon ranges from brownish to pink to white. Below 60 inches some pedons are reddish yellow or strong brown. Textures are dominantly loam, silt loam, clay loam, or silty clay loam, clay or silty clay textures occur in some pedons. With silicate clay content averaging 24 to 40 percent. Calcium carbonate equivalent ranges from 40 to 70 percent.
COMPETING SERIES: This is the Quanah series in the same family. Similar soils are the Angelo, Knippa, Lewisville, Mansic, Portales, Rowena, Set, and Springcreek soils. Quanah soils have less than 35 percent total clay in the upper part of the particle size control section. Angelo soils are dry in the moisture control section for longer periods of time. In addition, Uvalde soils are dry in the moisture control section for longer periods of time. Mansic, and Portales soils have more than 15 percent coarser than very fine sand, and are dry in the soil moisture control section for longer periods. Knippa and Rowena soils have at some season cracks 1 to 10 cm wide that reach to a depth of at least 20 inches. Set soils have carbonatic mineralogy. Springcreek soils are 20 to 40 inches to a lithic contact. Lewisville soils are moist in the moisture control section for longer periods.
GEOGRAPHIC SETTING: Nuvalde soils are on nearly level to gently sloping alluvial fans, mainly from limestone hills of the Edwards Plateau of Texas, but includes and nearly level stream terraces. The surface gradient generally is less than 2 percent, but ranges up to 5 percent on beveled edges of stream terraces. The soil formed in alluvium high in calcium carbonate. The climate is subhumid. Mean annual precipitation ranges from 20 to 28 inches. Frost free days range form 210 to 240 days and elevation ranges from 1150 to 2000 feet. Thornthwaite annual P-E indices range from 26 to 44, and mean annual temperature ranges from 63 to 67 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Mereta, Rowena, and Salga series and Karnes, Lipan, and Tobosa series. Karnes, Rowena, Salga, and Tobosa soils are on similar surfaces, in addition, Karnes soils have ochric epipedons and average more than 40 percent calcium carbonate equivalent in the control section. Lipan and Tobosa soils have intersecting slickensides. In addition, Lipan soils are in rounded depressions. Mereta soils are slightly higher in the landscape.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderate. Runoff is negligible on 0 to 1 percent slopes, very low on 1 to 3 percent slopes and low on 3 to 5 percent slopes.
USE AND VEGETATION: Mostly rangeland. A small acreage is cultivated to oats, wheat, cotton, and sorghums. Native vegetation is mostly sideoats grama, silver bluestem, vine-mesquite, buffalograss, condalia, and forbs.
DISTRIBUTION AND EXTENT: Central Edwards Plateau, North Central Prairie and Rolling Limestone Prairie of Texas. The series is extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Coleman County, Texas; 1968.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 13 inches (Ap and A horizons)
Cambic horizon - 13 to 21 inches (Bw horizon)
Calcic horizon - 21 to 84 inches (Bk1, Bk2 and BCk horizons)
ADDITIONAL DATA: NSSL sample S71TX154-001 from the series type location and from Shackleford County, Texas.