LOCATION FIELDCREEK TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Cumulic Haplustolls
TYPICAL PEDON: Fieldcreek fine sandy loam--in rangeland. (Colors are for dry soil unless otherwise stated).
A1--0 to 8 inches; dark brown (10YR 4/3) fine sandy loam, dark brown (10YR 3/3) moist; weak fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine roots; common fine pores; few pebbles of quartz and feldspar, mainly less than 1 inch in diameter; neutral; clear smooth boundary. (4 to 24 inches thick)
A2--8 to 25 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine subangular blocky and granular structure; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; many fine and few medium pores; few wormcasts; few mica flakes; neutral; gradual smooth boundary. (0 to 28 inches thick)
Bw1--25 to 48 inches; dark brown (7.5YR 4/4) loam, very dark brown (7.5YR 3/4) moist; weak medium prismatic structure parting to weak fine subangular blocky; slightly hard, friable, sticky and slightly plastic; few fine roots, few dark stains; common mica flakes; moderately alkaline; gradual smooth boundary. (0 to 30 inches thick)
Bw2--48 to 80 inches; brown (7.5YR 5/4) fine sandy loam, dark brown (7.5YR 4/4) moist; weak medium prismatic structure parting to weak fine subangular blocky; slightly hard, very friable, slightly sticky and slightly plastic; many mica flakes; 10 percent quartz and feldspar pebbles, mainly less than 2 inches across; slightly effervescent; moderately alkaline.
TYPE LOCATION: Llano County, Texas; from Texas Highway 16 in south Llano, 8.5 miles southeast on Texas Highway 71; 3.8 miles east on Ranch Road 3404 and 190 feet north in a grazed native pecan orchard. Latitude 30 degrees, 40 feet, 20 inches N; Longitude 98 degrees, 29 feet, 55 inches W.
RANGE IN CHARACTERISTICS: Thickness of alluvial sediments is greater than 80 inches. Weighted average clay content of the 10- to 40- inch control section ranges from 10 to 18 percent. Coarse fragments, mainly less than 3 inches across, range from none to 10 percent by volume in the control section. Some pedons have thin gravelly strata below a depth of 40 inches.
Thickness of the A horizon is 20 to 40 inches. The horizon has hue of 7.5YR or 10YR, value of 3 to 5, and chroma of 2 or 3. Texture is loamy sand, sandy loam, or fine sandy loam. Reaction ranges from slightly acid to moderately alkaline.
The Bw horizon has hue of 7.5YR or 10YR, value of 4 to 6, and chroma of 4 or 6. Texture is fine sandy loam, sandy loam, loam, or their gravelly counterparts. Siliceous and feldspar pebbles range from 1 to about 20 percent. Some pedons have buried A horizons with fine sandy loam or sandy clay loam textures. Reaction ranges from neutral to moderately alkaline. A few threads, films, and concretions of calcium carbonate are in some pedons, typically below a depth of 40 inches.
COMPETING SERIES: These are the Cyril (OK) series in the same family. Similar soils are the Bippus, Bosque, Gageby, Gowen, Oakalla, and Odem series. Cyril soils are calcareous throughout. Bippus, Bosque, Gageby, Gowen, and Oakalla soils are in a fine-loamy family. In addition, Oakalla soils contain more than 40 percent carbonates in the control section. The Odem series are in the hyperthermic family.
GEOGRAPHIC SETTING: Fieldcreek soils are on nearly level flood plains and low stream terraces along streams in the Central Basin. Slope ranges from 0 to 2 percent. The soil formed in alluvium derived from sedimentary and metamorphic sources. Mean annual precipitation ranges from 25 to 30 inches, and mean annual temperature ranges from 65 to 68 degrees. Frost free days range from 215 to 230 days, and elevation ranges from 1,000 to 1,400 feet. Thornthwaite PE indices range from 38 to 44.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the similar Oakalla soils and the Castell, Katemcy, Keese, Ligon, Lou, Nebgen, Oben, and Voca soils. Oakalla soils are in similar positions on flood plains. All the other soils are on nearby slopes, are in higher positions, and have bedrock within 60 inches. Castell, Katemcy, and Voca soils are in a fine family and have argillic horizons. Keese, Ligon, Nebgen and Oben soils are less than 20 inches thick over bedrock.
DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately rapid. Runoff is negligible. These soils flood rarely or occasionally for very brief periods, mainly during the spring months.
USE AND VEGETATION: Most areas are used for range, a few areas are used for pecan orchards or improved pasture. Native grasses include indiangrass, little bluestem, switchgrass, Scribner's panicum, and Texas wintergrass. The main tree vegetation consists of pecan, mesquite, elm, hackberry, and Texas persimmon. Greenbriar, prickly ash and hawthorne are common vines and shrubs, and there are a few prickly pear.
DISTRIBUTION AND EXTENT: In the Central Basin of Texas (MLRA 81). This series is of small extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Llano County, Texas; 1985. The name is from a community in Llano County.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - 0 to 25 inches (A1 and A2 horizons)
Cumulic feature - mollic epipedon extends to depths greater than 20 inches.
Cambic horizon - 25 to 80 inches (Bw horizons).
Soil Interpretation Record No.: TX1108