LOCATION TOBIN                   KS

Established Series
Rev. RMM, DJK
07/2020

TOBIN SERIES

The Tobin series consists of very deep, well drained soils that formed in silty alluvium. Tobin soils are on flood plains on river valleys in MLRA 73, Rolling Plains and Breaks. Slopes range from 0 to 2 percent. Mean annual precipitation is about 740 millimeters (29 inches) and the mean annual temperature is about 12 degrees C (54 degrees F).

TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Cumulic Haplustolls

TYPICAL PEDON: Tobin silt loam in rangeland at an elevation of 511 meters (1676 feet). (Colors are for dry soil conditions unless otherwise stated.)

A1--0 to 51 centimeters (0 to 20 inches); dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many fine roots; slightly acid; gradual smooth boundary.

A2--51 to 81 centimeters (20 to 32 inches); dark grayish brown (10YR 4/2) silt loam, very dark brown (10YR 2/2) moist; moderate medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; moderately alkaline; diffuse smooth boundary. (The combined thickness of the A horizons is 51 to 102 centimeters (20 to 40 inches) thick)

C--81 to 152 centimeters (32 to 60 inches); grayish brown (10YR 5/2) silt loam, dark grayish brown (10YR 4/2) moist; a few thin strata of dark grayish brown (10YR 4/2) silty clay loam, very dark grayish brown (10YR 3/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few fine roots; strong effervescence; moderately alkaline.

TYPE LOCATION: Ellsworth County, Kansas; about 6 kilometers (4 miles) west and 11 kilometers (7 miles) north of Ellsworth; located about 704 meters (2,310 feet) west and 18 meters (60 feet) south of the northeast corner of section 15, T. 14 S., R. 9 W.; Black Wolf USGS quadrangle; latitude 38 degrees 50 minutes 30.1 seconds N. and longitude 98 degrees 18 minutes 29.4 seconds W., WGS84.

RANGE IN CHARACTERISTICS:
Mollic epipedon: 50 to 100 centimeters (20 to 40 inches) thick
Depth to free carbonates: 38 to 100 centimeters (15 to 40 inches)
Depth to redoximorphic features: greater than 100 cm (40 inches)
Soil moisture regime: typic ustic
Soil temperature regime: mesic
Mean annual soil temperature: 13 to 14 degrees C (55 to 58 degrees F)
Particle size control section (weighted average) clay: 18 to 30 percent
Particle size control section (weighted average) fine sand or coarser: 0 to 14 percent

A horizon:
Hue: 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 1 to 3 dry or moist
Texture: silt loam or silty clay loam
Reaction: moderately acid to moderately alkaline
Some pedons have AC horizons.

C horizon:
Hue: 10YR
Value: 5 to 7 dry, 4 to 5 moist
Chroma: 2 or 3 dry or moist
Texture: silt loam, loam or silty clay loam
Reaction: moderately alkaline

Some pedons have more sandy or clayey strata below 40 inches.
Pedons with buried A horizons are common.

COMPETING SERIES: These are the Ackmen, Alcester, Coleridge, Gabaldon, Hord, Irak, Muir, Roxbury, Shell, Trementina and Vega series.
Ackmen and Trementina soils occur at higher elevations and are dry in the the soil moisture control section for six-tenths or more of the cumulative days per year when the soil temperature at a depth of 50 cm is higher than 5 degrees C (aridic ustic).
Alcester soils have a cambic horizon.
Coleridge soils are somewhat poorly drained and have a seasonal high water table from 45 to 105 cm.
Gabaldon, Roxbury, and Vega soils have free carbonates above a depth of 38 centimeters (15 inches).
Hord soils have rare to no flooding and have more soil development with Bw horizons (some make cambic).
Irak soils are moderately well or somewhat poorly drained and have a water table from 30 to 91 centimeters (12 to 36 inches).
Muir and Shell soils have carbonates deeper than 100 cm.

GEOGRAPHIC SETTING:
Parent material: silty alluvium
Landform: flood plains on river valleys
Slopes: 0 to 2 percent
Elevation: 350 to 825 meters (1150 to 2700 feet)
Mean annual precipitation: 560 to 810 millimeters (22 to 32 inches)
Mean annual air temperature: 12 to 14 degrees C. (53 to 57 degrees F.)
Precipitation pattern: precipitation is usually evenly distributed throughout the year with the exception of November through February being the driest months and May and June being the wettest months. Summer precipitation occurs during intense summer thunderstorms.
Frost-free period: 160 to 190 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Detroit, Hobbs, Hord, and Roxbury soils.
Detroit soils are on stream terraces and have greater than 35 percent clay in the particle size control section.
Hord soils are on stream terraces and have rare to no flooding.
Roxbury soils are on similar landform positions and have carbonates within 38 cm.
Hobbs soils are on similar landform positions and have fine stratification within 25 centimeters (10 inches) of the surface.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: well drained
Runoff: low
Saturated hydraulic conductivity: moderately high
Flooding: occasionally or frequently flooded

USE AND VEGETATION: Most areas are cultivated.
Principal crops are wheat, grain sorghum, and alfalfa.
Native vegetation is mid and tall grasses.

DISTRIBUTION AND EXTENT: Central and western Kansas; Land Resource Region H, Central Great Plains Winter Wheat and Range Region; MLRAs 73, Rolling Breaks and Plains and 74, Central Kansas Sandstone Hills. The series is of moderate extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Salina, Kansas

SERIES ESTABLISHED: Saline County, Kansas, 1952.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle-size control section: The zone from 25 to 100 centimeters (10 to 40 inches). (A1, A2, and C horizons)
Mollic epipedon: The zone from 0 to 81 centimeters (0 to 32 inches) (A1 and A2 horizons)

Keys to Soil Taxonomy: Twelfth edition, 2014

4/2015 DJK
Updated intro with MLRA and climate data. Added quad and lat/long to type location. Added soil moisture regime, temperature regime, depth to redox, and PSCS clay and fine sand or coarser to RIC. Updated competing series and geographically associated soils. Added elevation, precipitation pattern, and frost free days to geographic setting. Updated precipitation using 1981-2010 data. Added LRR and MLRAs to distribution and extent.

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National Cooperative Soil Survey
U.S.A.