LOCATION STYX TXEstablished Series
TAXONOMIC CLASS: Loamy, siliceous, active, thermic Arenic Paleustalfs
TYPICAL PEDON: Styx loamy fine sand--pasture. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 5 inches; pale brown (10YR 6/3) loamy fine sand, brown (10YR 4/3) moist; single grained; soft, loose; many fine roots; moderately acid; clear smooth boundary.
E1--5 to 18 inches; very pale brown (10YR 7/3) loamy fine sand, brown (10YR 5/3) moist; single grained; soft, loose; few fine roots; moderately acid; gradual smooth boundary.
E2--18 to 33 inches; very pale brown (10YR 8/3) loamy fine sand, pale brown (10YR 6/3) moist; single grained; slightly hard, very friable; few fine roots; slightly acid; clear wavy boundary. (Combined thickness of the A and E horizons are 20 to 40 inches)
Bt1--33 to 42 inches; brownish yellow (10YR 6/6) sandy clay loam, yellowish brown (10YR 5/6) moist; moderate medium subangular blocky structure; very hard, friable; few fine roots; few clay films on faces of peds; few uncoated sand grains; few strongly cemented concretions of iron; moderately acid; gradual smooth boundary.
Bt2--42 to 65 inches; prominently mottled light brownish gray (10YR 6/2), brownish yellow (10YR 6/6), and red (2.5YR 4/8) sandy clay loam; moderate medium blocky structure; very hard, friable; few fine roots; common clay films on faces of peds; few uncoated sand grains; few strongly cemented concretions of iron; moderately acid; gradual smooth boundary. (Combined thickness of the Bt horizon is 25 to 40 inches)
Bt/E--65 to 84 inches; distinctly mottled brownish yellow (10YR 6/6), yellowish brown (10YR 5/6) sandy clay loam; weak coarse prismatic structure; very hard, friable; few fine roots; few clay films on faces of peds; 5 to 10 percent light gray uncoated sand grains; few concretions of iron; strongly acid.
TYPE LOCATION: Kaufman County, Texas; about 12 miles southwest of Kaufman on Texas Highway 34 to junction with Farm Road 2451, 1 mile northwest on Farm Road 2451 and 0.75 mile southwest on county road; site is 500 feet south of road.
RANGE IN CHARACTERISTICS: Solum thickness is 60 to more than 80 inches. Combined thickness of the A and E horizons is 20 to 40 inches. Reaction is strongly acid through neutral. The A horizon has hue of 10YR, value of 5 to 7, and chroma of 2 to 4. The E horizons have hue of 10YR, value of 6 to 8, and chroma of 2 to 4. The texture of the A and E horizons is loamy fine sand or fine sand.
The Bt horizons are sandy clay loam or clay loam. The average clay content of the upper 20 inches ranges from 25 to 35 percent. They are very strongly acid to slightly acid. The Bt1 horizon is 7.5YR or 10YR, value of 5 or 7, and chroma of 6 to 8. A few mottles of strong brown (7.5YR 5/6) are present in some pedons. The Bt2 horizon is distinctly and prominently mottled gray, red, yellow or brown in hue of 2.5YR to 10YR, value of 4 to 7, and chroma of 1 to 8.
The Bt/E horizon is mottled in shades of gray, white, red, brown, and yellow in hues of 5YR to 10YR. It is very strongly acid to slightly acid and contains uncoated sand grains as coatings on peds and in small pockets. They comprise 5 to 15 percent of the matrix.
COMPETING SERIES: These are the Heaton and Silstid series in the same family and the similar Alum, Bastsil, Demona, Dutek, Konsil, Larue, Nimrod, Nobscot, Padina, Patilo, Selden, Silawa, and Wolfpen series. Alum and Demona soils have more than 35 percent clay in the Bt horizons. Bastsil, Konsil, and Selden soils have A and E horizons less than 20 inches thick. Dutek soils decrease in clay above 60 inches and lack mottles in lower Bt. Larue and Wolfpen soils are moist for longer periods of time in the moisture control section. Nimrod soils contain low chroma mottling within 30 inches of the surface. Nobscot soils lack mottles in the Bt and are dry for longer periods of time. Padina and Patilo soils have sandy A and E horizons more than 40 inches thick. Silawa soils decrease in clay above 60 inches and have A and E horizons less than 20 inches thick. Heaton and Silstid soils are on uplands, lack distinct gray mottles in the lower Bt and are deeper to a water table.
GEOGRAPHIC SETTING: These soils occupy nearly level to gently sloping high stream terraces. Slope gradients are mainly between 0 and 3 percent but range up to 5 percent. The soil formed in sandy and loamy alluvial sediments. The mean annual temperature ranges from 64 to 69 degrees F., and mean annual rainfall ranges from 32 to 40 inches. Thornthwaite P-E index is about 64. Frost free days range from 240 to 270 days and elevation ranges from 180 to 500 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the similar Dutek, Konsil, and Silawa series and the Axtell, Eufaula, Lufkin, Rader, and Tabor series. Axtell, Lufkin, and Tabor soils have clayey Bt horizons and are on slightly higher positions. Eufaula soils have sandy Bt horizons. Eufaula, Dutek, Konsil, and Silawa soils are on similar landscapes. Rader soils lack sandy A horizons and are on slightly higher positions.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is slow; Permeability is moderate.
USE AND VEGETATION: Most areas are used for pasture. A few areas are used for growing small grains for cool season grazing and truck crop production. Native vegetation is mainly post oak and blackjack oak, and greenbrier, with an understory of mid and tall grasses.
DISTRIBUTION AND EXTENT: Mainly in the timbered areas of north central Texas. The soil is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Kaufman County, Texas; 1973.
REMARKS: Styx soils were formerly included in the Dougherty series.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the A and E horizons from 0 to 33 inches.
Arenic feature - loamy fine sand texture from 0 to 33 inches.
Argillic horizon - the Bt horizons from 33 to 84 inches.
Pale feature - the Bt horizon does not decrease by as much as 20 percent of the maximum within 60 inches of the surface. and contains red mottles in the Bt2 horizon that meet the requirement for being common and coarse.
ADDITIONAL DATA: Data on Mineralogy and PSD from NSSL: S76TX-25-1, 76P0060; and S76TX-213-1, 76P0048.