LOCATION BENCHLEY                TX

Established Series
MRJ-GLL-JAW
09/2015

BENCHLEY SERIES

The Benchley series consists of very deep, moderately well drained, slowly permeable soils derived from residuum weathered from clayey residuum of the Cook Mountain Formation. These nearly level to moderately sloping soils are on ridges on dissected plains. Slope ranges from 0 to 8 percent but are dominantly 1 to 3 percent.

TAXONOMIC CLASS: Fine, smectitic, thermic Udertic Argiustolls

TYPICAL PEDON: Benchley loam, at an elevation of 94 m (311 ft), native pasture. (Colors are for moist soil unless stated).

A--0 to 25 cm (0 to 10 in); very dark brown (10YR 2/2) loam, very dark grayish brown (10YR 3/2) dry; moderate medium granular structure; hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; common fine pores; cracks from 0.75 to 1.5 cm (1/4 to 1/2 in)wide extend through the horizon; few reddish brown worm casts; 1 percent rounded ironstone pebbles mainly less than 1.5 cm (1/2 in)in diameter; slightly acid; clear smooth boundary. (15 to 41 cm [6 to 16 in] thick)

Bt--25 to 41 cm (10 to 16 in); very dark brown (10YR 2/2) clay loam, very dark grayish brown (10YR 3/2) dry; moderate medium subangular blocky structure parting to moderate very fine subangular blocky; hard, friable; sticky and plastic; common very fine and fine roots; common fine and few medium pores; cracks 0.75 to 1.5 cm (1/4 to 1/2 in) wide extend through the horizon; few pressure faces; less than 1 percent rounded ironstone pebbles about 0.75 to 1.5 cm (1/4 to 1/2 in) in diameter; common fine and medium distinct dark yellowish brown (10YR 4/6) masses of iron accumulation; slightly acid; clear smooth boundary. (0 to 38 cm [0 to 15 in] thick)

Btss1--41 to 76 cm (16 to 30 in); reddish brown (5YR 4/3) clay, reddish brown (5YR 4/4) dry; moderate medium angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine and medium pores; cracks from 0.75 to 1.5 cm (1/4 to 1/2 in)wide extend through the horizon; common pressure faces and slickensides; distinct patchy clay films on surface of peds and in some pores; less than 1 percent rounded ironstone pebbles about 0.75 to 1.5 cm (1/4 to 1/2 in)in diameter; many fine distinct light olive brown (2.5Y 5/4) and pale yellow (2.5Y 7/3) masses of iron accumulation; slightly acid; gradual wavy boundary.

Btss2--76 to 112 cm (30 to 44 in); light olive brown (2.5Y 5/4) clay, light yellowish brown (2.5Y 6/4) dry; moderate medium angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine and medium pores; common slickensides; distinct patchy clay films on surface of peds and in pores; less than 1 percent rounded ironstone pebbles about 0.75 to 1.5 cm (1/4 to 1/2 in)in diameter; many medium and coarse prominent red (2.5YR 4/8) masses of iron accumulation; slightly acid; gradual wavy boundary.

Btss3--112 to 137 cm (44 to 54 in); light olive brown (2.5Y 5/4) clay, light yellowish brown (2.5Y 6/4) dry; moderate medium angular blocky structure; very hard, very firm, very sticky and very plastic; few fine roots; few fine and medium pores; common slickensides; distinct patchy clay films on surface of peds and in pores; few fine iron manganese concretions; less than 1 percent rounded ironstone and siliceous pebbles about 0.75 to 1.5 cm (1/4 to 1/2 in)diameter; common medium prominent red (2.5YR 4/8) masses of iron accumulation; slightly acid; gradual wavy boundary. (Combined thickness of Btss horizon is 51 to 114 cm [20 to 45 in])

BCt--137 to 178 cm (54 to 70 in); light olive brown (2.5Y 5/4) clay loam, light yellowish brown (2.5Y 6/4) dry; weak medium subangular blocky structure; very hard, firm, sticky and plastic; few fine roots; few fine and medium pores; distinct patchy clay films on surface of peds and in some pores; few small slickensides; common iron manganese concretions; 5 percent rounded ironstone and siliceous pebbles mainly less than 1.5 cm (1/2 in)in diameter; common fine and medium faint pale yellow (2.5Y 7/4) masses of iron accumulation; neutral; gradual smooth boundary. (20 to 89 cm [8 to 35 in] thick)

Cdk--178 to 203 cm (70 to 80 in); light olive brown (2.5Y 5/6) shale with clay texture, light yellowish brown (2.5Y 6/4) dry; angular rock-like structure; very hard, very firm, very sticky and very plastic; few fine roots mainly along fractures; common fine and medium concretions and masses of calcium carbonate; few fine iron manganese concretions; less than 1 percent ironstone pebbles about 0.75 to 1.5 cm (1/4 to 1/2 in)in diameter; common medium faint pale yellow (2.5Y 7/4) masses of iron accumulation of surfaces of rock-like aggregates; slightly alkaline.

TYPE LOCATION: Brazos County, Texas: from the intersection of Texas Hwy. 21 and Texas Hwy. 6 in Bryan, 6.3 miles north on Hwy. 6 to intersection of OSR, 50 ft east and 75 ft south in pasture. Bryan West USGS Quadsheet; Latitude: approximately 30 degrees, 44 minutes, 47.1 seconds N; Longitude: approximately 96 degrees, 27 minutes, 20.6 seconds W; WGS84.

RANGE IN CHARACTERISTICS:
Soil Moisture: An ustic soil moisture regime. The soil moisture control section is dry in some or all parts for more than 90 days in normal years.
Soil Depth: 152 to more than 203 cm (60 to more than 80 in).
Rock fragments: amount-0 to 5 percent; kind-ironstone nodules, or sandstone; roundness-rounded or angular; cementation-indurated; size-gravel.
Thickness of mollic epipedon: 33 to 48 cm (13 to 19 in)
Depth to argillic horizon: 15 to 33 cm (6 to 13 in)
Depth to slickensides: 38 to 74 cm (15 to 29 in)
Depth to secondary carbonates: 124 to 203 cm (49 to 80 in)
Depth to redox features (when present): 15 to 23 cm (6 to 9 in)
Depth to gypsic horizon (when present): 157 to 203 cm (62 to 80 in)
Depth to densic material (when present): 152 to 203 cm (60 to 80 in)
Particle size control section: 35 to 55 percent
Clay content: 25 to 100 cm (10 to 40 in)
Surface features: When dry, cracks about 1 cm (1/2 in) wide are in the argillic horizon and extend to a depth of 30 cm or more (12 in or more).

A Horizon:
Hue: 7.5YR 0r 10YR
Value: 2 or 3
Chroma: 1 to 3
Texture: loam, sandy clay loam, or clay loam
Rock Fragments: amount-0 to 5 percent; size-2 to 5 mm; kind-ironstone nodules
Clay content: 20 to 29 percent
Reaction: moderately acid to neutral

Bt Horizon (where present):
Hue: 2.5YR, 7.5YR, 10YR, or 2.5Y
Value: 2 or 5
Chroma: 1 to 8
Texture: sandy clay loam, clay loam or clay
Clay films: location-on faces of peds and in pores
Rock Fragments: amount-0 to 5 percent; size-2 to 75 mm; kind-ironstone nodules, or sandstone
Redox concentrations: amount-none to common; size-fine to medium; shades-brown, yellow or red
Reaction: moderately acid to neutral

Btss1 and Btss2 Horizon:
Hue: 2.5YR to 2.5Y
Value: 3 to 5
Chroma: 2 to 8
Texture: clay
Clay films: location-on vertical faces of peds
Slickensides/Pressure faces: amount-few to many
Rock Fragments: amount-0 to 2 percent; size-2 to 75 mm; kind-ironstone nodules, or sandstone
Redox concentrations: amount-few to many; size-fine to medium; shades-olive, brown, red, or yellow
Reaction: moderately acid to neutral

Btss3 and Btkss Horizon:
Hue: 10YR, 2.5Y or 5Y
Value: 4 to 6
Chroma: 3 to 8
Texture: clay loam or clay
Slickensides/Pressure faces: amount-few to many
Rock Fragments: amount-0 to 2 percent; size-2 to 5 mm; kind-ironstone nodules
Redox concentrations: amount-few to many, shades-red, yellow, or brown
Redox depletions: amount-none or common, shades-gray
Identifiable secondary carbonate: amount-none to few; size-fine
Reaction: moderately acid to slightly alkaline

BCt, BCtk, BCk or BCkss Horizon:
Hue: 7.5YR to 5Y
Value: 4 to 7
Chroma: 3 to 8
Texture: sandy clay loam, clay loam, clay
Slickensides/Pressure faces: amount-none to common
Rock Fragments: amount-0 to 1 percent; size-2 to 75 mm; kind-ironstone nodules, sandstone
Redox concentrations: amount-few to common; size-fine; shades-red, yellow, or brown
Redox depletions: amount-none or common; size-fine; shades-gray
Identifiable secondary carbonate: amount-none to common; size-fine to medium
Gypsum crystals: amount-none to common
Reaction: slightly acid to moderately alkaline

The Cd, Cdy or Cdk horizon:
Hue: 7.5YR, 10YR, or 2.5Y
Value: 5 to 6
Chroma: 4 to 8
Texture: clay loam or clay
Rock Fragments: amount-0 to 10 percent; size-2 to 75 mm; kind-
Identifiable secondary carbonate: amount-none to common
Gypsum crystals: amount-none to common
Reaction: slightly acid to moderately alkaline.

COMPETING SERIES: These are the Caradan (TX), Durant (OK), Flatonia (TX), and Foraker (OK) series in the same family. Similar soils are the Blum, Bonham, Culp, Elmendorf, and Hallettsville series.
Caradan soils: calcic horizons; do not have redoximorphic features due to wetness in the argillic horizon.
Durant and Foraker soils: lower mean annual temperature; a shorter growing season. In addition, Foraker soils have Cr horizons between 51 to 102 cm (20 and 40 in).
Flatonia soils: Cr horizon between 102 and 152 cm (40 and 60 in)
Blum and Culp soils: mixed mineralogy.
Bonham soils: udic moisture regime.
Elmendorf soils: moist in the moisture control section for longer periods; hyperthermic soil temperature regime
Hallettsville soils: an abrupt textural change between the A and Bt horizons (Pale).

GEOGRAPHIC SETTING:
Parent material: clayey residuum weathered from mudstone of the Cook Mountain Formation
Landscape: Dissected plains
Landform: Ridge
Slope: 0 to 8 percent, but mostly 1 to 3 percent
Mean annual precipitation: 889 to 1094 mm (35 to 41 in)
Precipitation Pattern: Precipitation mostly falls in the spring and fall months. The summer months are the driest.
Thornthwaite P-E Index: 54 to 64
Mean annual air temperature: 18.6 to 21.1 degrees C (66 to 70 degrees F)
Frost-free period: 240 to 276 days
Elevation: 64.8 to 174.6 m (212.6 to 572.8 ft)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bremond, Crockett, Dimebox, Mabank, and Wilson series.
Bremond, Mabank, and Wilson soils: have an ochric epipedon; on slightly lower terrace positions commonly near drainageways.
Crockett and Dimebox soils: on similar landscape positions or on slightly higher convex positions. These soils do not have mollic epipedons. Also, the Dimebox series is clayey throughout and has large slickensides.

DRAINAGE AND PERMEABILITY: Moderately well drained. Permeability is slow. Runoff is low on slopes less than 1 percent, medium on 1 to 5 percent slopes, and high on 5 to 8 percent slopes.

USE AND VEGETATION: Typically cultivated crops are cotton, grain sorghum, corn and small grain. Bermudagrass pastures are common. Native vegetation includes little bluestem, big bluestem, Indiangrass, brownseed paspalum and various forbes.

DISTRIBUTION AND EXTENT: The Blackland Prairies of East Central Texas (MLRA 86B). The series is of moderate extent.

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

SERIES ESTABLISHED: Leon County, Texas; 1985. The name is from a community near the Brazos-Robertson county line.

REMARKS: This soil was formerly included within the Bonham and Culp series.

Diagnostic horizons and features recognized in this pedon are:

Mollic epipedon: 0 to 41 cm (0 to 16 in); includes the A horizon and upper part of the argillic horizon in most pedons.
Argillic horizon: 25 to 178 cm (10 to 70 in). (Bt, Btss, Btss2, Btss3, and BCt horizons)
Slickensides: 41 to 137 cm (16 to 54 in). (Btss, Btss2, and Btss3 horizons)
Densic Materials: 178 to 203 cm (70 to 80 in). (Cdk horizon)
Identifiable Secondary Carbonate: 178 to 203 cm (70 to 80 in). (Cdk horizon)
Redox features: 25 to 203 cm (10 to 80 in). (Bt, Btss, Btss2, Btss3, BCt, Cdk horizon)
Vertic properties: Slickensides in the argillic horizon.

ADDITIONAL DATA: KSSL S1962TX041090 TAMU S62TX-21-90; K1243-1249

Taxonomic Version: Keys to Soil Taxonomy, Twelfth Edition, 2014

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National Cooperative Soil Survey
U.S.A.