LOCATION BONTI TX

Established Series
Rev. BJW-GLL-CLN
12/2013

BONTI SERIES

The Bonti series consists of moderately deep to sandstone, well drained, moderately slowly permeable soils that formed in residuum derived from interbedded sandstone and claystone of Pennsylvanian age. These very gently sloping to steep soils occur on summits and shoulders of ridges on hills. Slope ranges from 1 to 40 percent. Mean annual precipitation is about 787 mm (31 in) and mean annual air temperature is about 18.3 degrees C (65 degrees F).

TAXONOMIC CLASS: Fine, mixed, active, thermic Ultic Paleustalfs

TYPICAL PEDON: Bonti very fine sandy loam, very stony--in rangeland.
(Colors are for dry soil unless otherwise stated.)
The Surface is covered by about 15 percent stones and 3 percent cobbles and gravel of sandstone. The average distance between stones is 0.7 m (2 ft).

A--0 to 10 cm (0 to 4 in); brown (10YR 4/3) very fine sandy loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; slightly hard, friable; many fine and few medium roots; slightly acid; clear smooth boundary. Thickness is 5 to 25 cm (2 to 10 in)

E--10 to 20 cm (4 to 8 in); light brown (7.5YR 6/4) very fine sandy loam, brown (7.5YR 4/4) moist; weak fine subangular blocky structure; hard, friable; many fine roots; 5 percent subangular sandstone gravel; moderately acid; clear smooth boundary. Thickness is 0 to 15 cm (0 to 6 in)

Bt1--20 to 50 cm (8 to 20 in); red (2.5YR 4/6) clay, dark red (2.5YR 3/6) moist; moderate very fine and fine angular blocky structure; very hard, firm; many fine roots; thin continuous clay films on faces of peds; moderately acid; gradual smooth boundary.

Bt2--50 to 76 cm (20 to 76 in); yellowish red (5YR 5/6) clay loam; yellowish red (5YR 4/6) moist; few fine distinct dark red and few fine faint reddish yellow mottles; moderate fine angular blocky structure; very hard, firm; few fine roots; thin continuous clay films on faces of peds; moderately acid; abrupt boundary. Combined thickness of the Bt horizons is 36 to 86 cm (14 to 34 in)

Cr--76 to 203 cm (30 to 80 in); brownish yellow weakly to moderately cemented sandstone.

TYPE LOCATION: Erath County, Texas; 14.5 miles northwest of Stephenville on Texas Highway 108, 4.5 miles northeast on Farm Road 1715, 4.4 miles north on county road 118 (1.4 mile north of Russell Chapel Cemetery), 100 feet west in wooded area.
USGS topographic quadrangle: Gordon, TX; Latitude: 32 degrees, 30 minutes, 10.00 seconds N; Longitude: 98 degrees, 18 minutes, 23.00 seconds W; Datum: WGS84.
UTM Easting 565156.0 m, UTM Northing 3596379.0 m, UTM Zone 14.

RANGE IN CHARACTERISTICS:
Depth to paralithic contact: 51 to 102 cm (20 to 40 in)
Depth to argillic and abrupt textural change: 10 to 40 cm (4 to 16 in)
Surface fragments: 0 to 50 percent total; 0 to 15 percent boulders; 0 to 25 percent stones; 0 to 10 percent cobbles and gravel; size ranges from less than 75 mm (3 in) to 1219 mm (48 in); silica and iron oxide cemented conglomerate or sandstone

Particle-size control section (weighted average)
Clay content: 35 to 56 percent clay

A Horizon:
Hue: 7.5YR, 10YR
Value: 4 to 6
Chroma: 2 to 4
Texture: very fine sandy loam, fine sandy loam or loamy fine sand
Clay content: 5 to 20 percent
Rock fragments: 0 to 15 percent by volume; sandstone gravel, cobbles, and stones
Reaction: moderately acid to neutral

E Horizon: (where present)
Hue: 7.5YR, 10YR
Value: 5 to 7
Chroma: 2 to 6
Texture: very fine sandy loam, fine sandy loam or loamy fine sand
Clay content: 5 to 20 percent
Rock fragments: 0 to 15 percent by volume; sandstone gravel, cobbles, and stones
Reaction: moderately acid or neutral

Bt Horizons: (BC horizon where present)
Hue: 2.5YR or 5YR
Value: 4 or 6
Chroma: 4 to 8
Texture: clay, sandy clay, or clay loam
Clay content: 35 to 56 percent
Rock fragments: 0 to 5 percent by volume; sandstone gravel and cobbles
Base saturation: 50 to 75 percent
Reaction: strongly acid to moderately acid

Cr Horizon:
Texture: weakly to moderately cemented sandstone bedrock that is interbedded with thin layers of strongly cemented sandstone or noncemented claystone bedrock

COMPETING SERIES: These are the Birome, Darst, Gause, and Travis series in the same family. Similar soils are the Bluegrove, Newcastle, Vashti, and Windthorst series.
Birome soils: receive more rainfall and occur in the East Cross Timbers (MLRA 84C) and are derived from a different formations of sandstone.
Darst soils: occurs over mudstone or siltstone.
Guase and Travis soils: do not have bedrock within 102 cm (40 in) and occur on terraces.
Bluegrove soils: do not have abrupt textural change and have base saturation of more than 75 percent in the Bt horizon.
Newcastle soils: have less than 35 percent clay in the particle-size control section and a base saturation of more than 75 percent in the Bt horizon.
Vashti soils: have less than 35 percent clay in the particle-size control section and redoximorphic features in the lower horizons.
Windthorst soils: do not have bedrock within 102 cm (40 in) and have base saturation of more than 75 percent in the Bt horizon.

GEOGRAPHIC SETTING:
Parent material: Loamy and/or clayey residuum weathered from sandstone and/or claystone over sandstone, mainly of Pennsylvanian age
Landscape: hills
Landform: summits, shoulders, and back slopes of ridges
Slope: dominantly 1 to 5 percent on summits, but range to 40 percent on side slopes
Mean annual precipitation: 660 to 889 mm (26 to 35 in)
Thornthwaite annual P-E index: 40 to 50
Mean annual air temperature: 17.8 to 18.9 degrees C (64 to 66 degrees F)
Frost-free period: 215 to 245 days
Elevation: 228.6 to 533.4 m (750 to 1,750 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Exray, Loving, Owens, Shatruce, and Truce series.
Exray soils: are less than 50 cm (20 in) deep to sandstone bedrock and occur on shoulders of ridges.
Loving soils: have a loamy particle-size control section and occur on shoulder positions of ridges.
Owens soils: are clayey throughout over claystone bedrock, and occur mainly on low convex knolls and south-facing noseslopes and sideslopes.
Shatruce soils: formed in residuum from claystone bedrock and occur on bouldery sideslopes over claystone.
Truce soils: are 100 to 150 cm (40 to 60 in) deep to claystone bedrock and occur on footslopes of ridges.

DRAINAGE AND PERMEABILITY: Well drained. Permeability is moderately slow. Runoff is medium on 1 to 5 percent slopes, high on 5 to 20 percent slopes, and very high on 20 to 40 percent slopes.

USE AND VEGETATION: The major use is livestock grazing. The native plant community is mainly little and big bluestem, indiangrass, sideoats grama, Arizona cottontop, sand lovegrass, switchgrass, ragweed, blackjack, and post oak.

DISTRIBUTION AND EXTENT: North-central Texas; LRR H - Central Great Plains Winter Wheat and Range Region, MLRA 80B - Texas north-central prairies; The series is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas

SERIES ESTABLISHED: Erath County, Texas; 1970.

REMARKS:
Edited 12/2013 (RFG-SCP): Changed to tabular format and included metric values. Updated fragments and the competing series, geographic setting, and associated soils sections.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 20 cm (0 to 8 in)(A and E horizons).
Argillic horizon: 20 to 76 cm (8 to 30 in)(Bt1 and Bt2 horizons).
Paralithic Contact: 76 cm (30 in)(top of Cr horizon).
Paralithic material: 76 to 203 cm (30 to 80 in)(Cr horizon).
Ultic feature: base saturation of the Bt horizons is less than 75 percent.
Paleustalf feature: abrupt textural change at 20 cm (8 in).

ADDITIONAL DATA: KSSL data from Erath County, Texas (S79TX-143-003); SDHPT data from Eastland County, Texas (S69TX-067-001) and Parker County, Texas (S70TX-184-005).

Taxonomic version: Keys of Soil Taxonomy, Eleventh Edition, 2010

National Cooperative Soil Survey
U.S.A.