LOCATION SILSBEE TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, semiactive, thermic Typic Paleudults
TYPICAL PEDON: Silsbee fine sandy loam--woodland.
(Colors are for moist soil unless otherwise stated.)
A--0 to 5 inches; brown (10YR 5/3) fine sandy loam; moderate medium granular structure; soft, friable; many very fine to coarse roots; many fine and medium pores; very strongly acid; clear smooth boundary. ( 3 to 7 inches thick)
E--5 to 15 inches; 80 percent light yellowish brown (10YR 6/4) and 20 percent pale brown (10YR 6/3) fine sandy loam; moderate medium subangular blocky structure; slightly hard, friable; many very fine to medium and common coarse roots; many fine and common medium pores; very strongly acid; clear smooth boundary. ( 5 to 19 inches)
Bt1--15 to 30 inches; yellowish red (5YR 5/8) sandy clay loam; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, firm; many fine and medium roots; common very fine and fine pores; 5 percent distinct yellowish red (5YR 4/6) clay films on surfaces of peds; 3 percent ironstone nodules; strongly acid; gradual smooth boundary.
Bt2--30 to 49 inches; yellowish red (5YR 5/6) sandy clay loam; moderate medium and coarse prismatic structure parting to moderate medium subangular blocky; hard, firm; common very fine and fine roots; common very fine and fine pores; 4 percent faint yellowish red (5YR 4/6) and (5YR 5/8) clay films on surfaces of peds; 3 percent fine rounded ironstone nodules; strongly acid; gradual wavy boundary.
Bt3--49 to 58 inches; strong brown (7.5YR 5/8) sandy clay loam; weak medium prismatic structure parting to moderate medium subangular blocky; hard, firm; common fine and medium roots; common very fine pores; 2 percent prominent yellowish red (5YR 4/6) clay films and 2 percent distinct yellowish red (5YR 5/8) clay films on surfaces of peds; 2 percent fine rounded ironstone concretions; 1 percent fine rounded red (2.5YR 4/6) plinthite; 2 percent fine prominent red (2.5YR 4/6) iron concentrations with sharp boundaries; strongly acid; gradual wavy boundary.
Bt4--58 to 71 inches; strong brown (7.5YR 5/8) sandy clay loam; weak medium prismatic structure parting to moderate medium subangular blocky; hard, firm; common very fine and fine roots; common very fine pores; 5 percent prominent yellowish red (5YR 4/6) clay films and 1 percent distinct yellowish red (5YR 5/8) clay films on surfaces of peds; 3 percent fine red (2.5YR 4/6) plinthite; 2 percent fine prominent red (2.5YR 4/6) iron concentrations with sharp boundaries; strongly acid; gradual wavy boundary.
Bt5--71 to 80 inches; strong brown (7.5YR 5/6) sandy clay loam; weak medium prismatic structure parting to moderate medium subangular blocky; hard, firm; common very fine roots; common fine and medium pores; 2 percent distinct strong brown (7.5YR 5/6) clay films on surfaces of peds; 3 percent fine plinthite; 2 percent fine prominent red (2.5YR 4/6) iron concentrations with sharp boundaries; strongly acid. (The combined thickness of the Bt subhorizons is 55 to 69 inches)
TYPE LOCATION: Hardin County, Texas; from the intersection of Farm Road 418 and Farm Road 1122 in Silsbee; 0.4 mile northwest on Farm Road 418 to county road; 0.1 mile north and 1.9 mile northwest on county road to forest road; 0.7 mile west on forest road; 75 feet north in forest. (Latitude 30N, 25, 26; Longitude 94W, 14, 34)
RANGE IN CHARACTERISTICS: Solum thickness is more than 80 inches. Weighted average clay content of the particle-size control section is 18 to 30 percent. Base saturation ranges from 25 to 35 percent. Reaction ranges from extremely acid to strongly acid throughout.
The A horizon has hue 10YR, value of 4 to 6, and chroma of 3 or 4. Texture is fine sandy loam or very fine sandy loam.
The E horizon has hue 10YR, value of 5 to 7, and chroma of 3 or 4. Texture is fine sandy loam or very fine sandy loam.
The upper Bt horizons have hue 2.5YR or 5YR, value of 4 or 5, and chroma of 6 to 8. Texture is loam, sandy clay loam or clay loam.
The lower part of the Bt horizons have hue of 5YR or 7.5YR, value of 5 to 7, and chroma of 6 to 8. Texture is fine sandy loam, loam or sandy clay loam. Iron concentrations are few to many in shades of yellow, brown, or red. Plinthite ranges from 1 to 4 percent.
COMPETING SERIES: These include the Addielow, Allen, Avilla, Bama, Dubach, Etowah, Holston, Ironcity, Leesburg, Lytle, Minvale, Nella, Noboco, Octavia, Pikeville, Ruston, Sailes, and Warnock series in the same family. Addielow soils have an ochric pedon more than 20 inches thick and the upper Bt horizons have a yellower hue. Avilla and Pikeville soils have more than 15 percent coarse fragments in the lower Bt. Allen soils formed in alluvium or colluvium derived from sandstone and shale. Bama soils have a CEC to clay ratio of less than 0.24 in the particle-size control section. Etowah soils formed in alluvium or colluvium that is underlain by limestone. Dubach, Holston, Noboco, and Warnock soils have hue of 7.5YR or yellower throughout. Ironcity, Leesburg, Minvale, Nella, and Octavia soils have sandstone or chert gravels in the Bt horizon. Lytle soils formed from loess-mantled coastal plain sediments. Ruston soils are bisequal, with a glossic horizon in the lower part. Sailes soils formed in Tertiary-aged formations containing glauconitic parent materials.
GEOGRAPHIC SETTING: Silsbee soils are on plane to slightly convex, gently sloping to strongly sloping uplands. Slopes are 1 to 12 percent. These soils are on the flatwoods east of the Trinity River. The soils formed in loamy sediments of the Lissie Formation of early to mid Pleistocene age. Mean annual precipitation ranges from 48 to 56 inches. Mean annual temperature ranges 67 to 69 degrees F. Frost free days range from 240 to 270. Elevation ranges from 25 to 150 feet. The Thornthwaite P-E index is 68 to 80.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kirbyville and Otanya soils. Kirbyville soils are moderately well drained and are on lower landscape positions. Otanya soils have a subsoil yellower than 5YR and are on similar to lower landscape positions.
DRAINAGE AND PERMEABILITY: Silsbee soils are well drained. Runoff is low on 3 to 5 percent, and medium on 5 to 12 percent slopes. Permeability is moderate.
USE AND VEGETATION: Used primarily for woodland and wildlife habitat. Some areas are used for pastureland. Pastures are bahiagrass and improved bermudagrass. Native vegetation is longleaf pine, yaupon, bluestems, panicums and paspalums.
DISTRIBUTION AND EXTENT: The Western Gulf Coast Flatwoods (MLRA 152B) of southeast Texas. The series is of moderate extent.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Hardin County, Texas; 1998.
REMARKS: The Silsbee soils were formerly inluded with the Otanya and Attoyac series.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon--0 to 15 inches (A and E horizons).
Argillic horizon--15 to 80 inches (Bt horizon).
SOIL INTERPRETATION RECORD NUMBER: TX1337
ADDITIONAL DATA: Texas A&M University Soil Characterization Lab data on sample (S95TX-199-005) from type location in Hardin County, TX.