LOCATION TINN TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Typic Hapluderts
TYPICAL PEDON: Tinn clay--cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 6 inches; black (10YR 2/1) clay, very dark gray (10YR 3/1)
dry; moderate coarse angular blocky structure parting to moderate very fine and fine angular blocky structure; very hard, very firm; plastic; few fine roots; few fine and medium pores; slightly effervescent; moderately alkaline; abrupt smooth boundary. (4 to 8 inches thick)
A--6 to 18 inches; black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate coarse angular blocky structure parting to moderate very fine and fine angular blocky; very hard, very firm; few fine roots; few fine and medium pores; common pressure faces; few fine slickensides; about 2 percent fine siliceous pebbles, and about 2 percent fine ironstone pebbles; few worm casts; few medium grayish brown (2.5Y 5/2) streaks along root channels; slightly effervescent; moderately alkaline; gradual wavy boundary. (6 to 15 inches thick)
Bss1--18 to 28 inches; black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate coarse angular blocky structure parting to moderate fine and medium angular blocky; very hard, very firm; few fine roots; few fine and medium pores; common fine pressure faces; common fine slickensides; about 2 percent fine siliceous pebbles, and about 2 percent fine ironstone pebbles; few worm casts; few medium grayish brown (2.5Y 5/2) streaks along root channels; slightly effervescent; moderately alkaline; gradual wavy boundary. (8 to 20 inches thick)
Bss2--28 to 54 inches; black (10YR 2/1) clay, very dark gray (10YR 3/1) dry; moderate coarse angular blocky structure parting to moderate fine and medium angular blocky structure; very hard, very firm; few fine roots; few fine and medium pores; many prominent grooved slickensides that range from 5 to 10 cm across; most slickensides are oriented at 45 degrees; few fine black concretions; few medium calcium carbonate concretions that are pitted; about 2 percent siliceous pebbles; about 2 percent shell fragments; few worm casts; few coarse very dark gray (10YR 3/1) masses; slightly effervescent;
moderately alkaline; gradual wavy boundary. (0 to 30 inches thick)
Bss3--54 to 72 inches; very dark gray (10YR 3/1) clay, dark gray (10YR 4/1) dry; moderate coarse angular blocky structure parting to moderate fine and medium angular blocky; very hard, very firm; few fine roots; few fine and medium pores; common prominent grooved slickensides up to 1 meter across, slickensides are oriented at 45 to 60 degrees; few fine and medium calcium carbonate concretions that are pitted; few worm casts; slightly effervescent; moderately alkaline; gradual wavy boundary. (10 to 24 inches thick)
Bkss--72 to 80 inches; very dark grayish brown (2.5Y 3/2) clay, dark grayish brown (2.5Y 4/2) dry, moderate coarse angular blocky structure parting to moderate fine and medium angular blocky; very hard, very firm; few fine roots; few fine and medium pores; few fine grooved slickensides up to 50 cm across, slickensides are oriented at 45 to 60 degrees; common fine and medium calcium carbonate concretions; few fine and medium masses of gypsum; few black (10YR 2/1) streaks; slightly effervescent; moderately alkaline.
TYPE LOCATION: Limestone County, Texas; from the intersection of Farm Road 171 and Farm Road 73 in Coolidge, 2.8 miles northeast on Farm Road 73, 0.6 miles north on county road, and 400 feet east on Pin Oak Creek floodplain in cropland.
RANGE IN CHARACTERISTICS: Solum thickness is greater than 80 inches. Reaction is slightly alkaline or moderately alkaline. Effervescence ranges from very slight to strong. Weighted average clay content of the particle size control section ranges from 40 to 60 inches. Texture is silty clay or clay throughout. Undisturbed areas have subdued gilgai, with microhighs 2 to 6 inches higher than microlows. Slickensides and/or wedge-shaped aggregates begin at depths from 6 to 20 inches, becoming more distantly expressed between 20 and 60 inches. The soil cracks when dry and the cracks are 0.5 inch to about 2 inches wide and extend to a depth of more than 12 inches. The cracks remain open from 60 to 90 cumulative days in most years.
The A horizon has dark colors in hue of 10YR to 5Y, value of 2 or 3, and
chroma of 1. Texture is silty clay or clay.
A Bw horizon is present in some pedons. Where present, the colors and textures are similar to those of the A horizon.
The Bss and Bkss horizons have hue of 10YR to 5Y, value of 3 to 6, and chroma of 1 to 4. Redox concentrations in shades of brown, olive or yellow range from none to common. Calcium carbonate masses and concretions range from none to
common.
COMPETING SERIES: These are the
Eastham and
Hallsbluff series. Similar
soils are the
Branyon,
Burleson,
Kaufman, and
Trinity soils. Eastham soils are not calcareous in the upper 20 inches. Hallsbluff soils have a mollic epipedon with chroma of 2. Branyon and Burleson soils are Usterts. In addition, Burleson soils are noncalcareous in the upper 20 inches. Kaufman and Trinity soils have very-fine control sections.
GEOGRAPHIC SETTING: Tinn soils are on nearly level flood plains. Slopes are mainly less than 1 percent, but some are as much as 2 percent. The soil formed in calcareous clayey alluvium. Mean annual precipitation ranges from 32 to 42 inches, and mean annual temperature ranges from 64 to 68 degrees F. Frost free days range 230 to 270 days and elevation ranges from 250 to 550 feet. Thornthwaite P-E indices exceed 44.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Branyon, Burleson, Ferris, Heiden, Houston Black, and Trinity series. Branyon and Burleson soils are on higher terrace positions. Ferris and Heiden soils have chroma of 2 or more in the upper 12 inches. Houston Black soils have greater amplitude of waviness and are on uplands in a higher position. Trinity soils have very-fine particle-size control sections and are in similar positions.
DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is very slow. Runoff is low. Flooding is common except where the soil is protected. Duration of flooding is very brief or brief.
USE AND VEGETATION: Most areas are in pasture or cultivated to crops such as cotton, corn, sorghums, or small grains. Native vegetation is elm, hackberry, oak, and ash, with an understory of grasses such as species of paspalums and panicums.
DISTRIBUTION AND EXTENT: Mainly in central Texas on streams draining the Blackland Prairies (MLRA 86A). The series is extensive.
MLRA OFFICE RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Hill County, Texas; 1975.
REMARKS: Classification of the Tinn series was changed from Vertic Haplaquolls to Typic Pelluderts (3/88). This change was based on several years study and analysis of the soils mapped in the Tinn series. The series type location was moved from Hill County to Limestone County to a pedon that is near the center of the series range in characteristics and near the center of the geographic distribution. Classification change from Typic Pelluderts to Typic Hapluderts based on Amendment 16, SOIL TAXONOMY (2/94).
Diagnostic horizons and features recognized in this pedon are:
Mollic colors - throughout this pedon.
Vertic Properties - slickensides from 6 to 80 inches.
SOIL INTERPRETATION RECORD NO: TX0456