LOCATION THOMAS                  MI

Established Series
Rev. JEF-NWS
08/2012

THOMAS SERIES

The Thomas series consists of very deep, poorly drained or very poorly drained soils formed in organic materials less than 41 cm (16 inches) thick overlying loamy till or lacustrine materials. These soils are on till plains and lake plains. Slope ranges from 0 to 2 percent. Mean annual precipitation is about 762 mm (30 inches), and mean annual temperature is about 7.8 degrees C (46 degrees F).

TAXONOMIC CLASS: Fine-loamy, mixed, semiactive, calcareous, mesic Histic Humaquepts

TYPICAL PEDON: Thomas muck, on a nearly level area in a cultivated field. (Colors are for moist soil unless otherwise stated.)

Oap--0 to 23 cm (9 inches); black (10YR 2/1) broken face and rubbed muck; moderate medium granular structure; friable; many fine roots; neutral; abrupt smooth boundary. [20 to 38 cm (8 to 15 inches) thick]

B1g--23 to 43 cm (9 to 17 inches); dark gray (10YR 4/1) clay loam; weak coarse subangular blocky structure; firm; common fine roots; many medium prominent yellowish brown (10YR 5/6) masses of oxidized iron; 3 percent gravel; 1 percent cobbles; slightly effervescent; slightly alkaline; clear wavy boundary. [10 to 23 cm (4 to 9 inches) thick]

C1g--43 to 96 cm (17 to 38 inches); gray (10YR 5/1) clay loam; weak medium subangular blocky structure; firm; few fine roots; many medium prominent yellowish brown (10YR 5/6 and 5/8) masses of oxidized iron; 2 percent gravel; 1 percent cobbles; strongly effervescent; moderately alkaline; abrupt wavy boundary. [25 to 61 cm (10 to 24 inches) thick]

C2g--96 to 152 cm (38 to 60 inches); gray (10YR 6/1) loam; massive; friable; many coarse prominent yellowish brown (10YR 5/6) and few medium distinct light yellowish brown (10YR 6/4) masses of oxidized iron; 4 percent gravel; 1 percent cobbles; slightly effervescent; moderately alkaline.

TYPE LOCATION: Gratiot County, Michigan; about 1 mile west of Ithaca; 1,950 feet east and 550 feet south of the northwest corner of sec. 2, T. 10 N., R. 3 W.

RANGE IN CHARACTERISTICS:
Thickness of the solum: typically 36 to 61 cm (14 to 24 inches) but ranges from 25 to 61 cm (10 to 24 inches)
Mean annual soil temperature: 8 to 11 degrees C (47 to 52 degrees F)

Oap or Oa horizon:
Hue: 10YR or is neutral
Value: 2 or 3
Chroma: 0 to 2
Texture: muck, mucky sandy loam, mucky silt loam, or mucky loam
Reaction: neutral to moderately alkaline

Bg horizon:
Hue: 10YR or 2.5Y
Value: 4 to 6
Chroma: 1 or 2
Texture: clay loam, sandy clay loam, loam, silt loam, or silty clay loam
Rock fragment content: 0 to 14 percent
Reaction: slightly alkaline or moderately alkaline; slightly or strongly effervescent

Cg horizon:
Hue: 5YR to 10YR
Value: 4 to 6
Chroma: 1 to 4
Texture: clay loam, loam, silt loam, sandy clay loam, or silty clay loam; some pedons contain strata of silty clay, silty loam, or sand
Rock fragment content: 0 to 14 percent
Reaction: slightly alkaline or moderately alkaline; slightly or strongly effervescent

COMPETING SERIES: There are no other series in the same family.

GEOGRAPHIC SETTING: Thomas soils are on nearly level till plains and lake plains. Slope ranges from 0 to 2 percent. They formed in organic materials less than 41 cm (16 inches) thick overlying calcareous loamy till or lacustrine materials. Mean annual precipitation ranges from 711 to 864 mm (28 to 34 inches). Mean annual temperature ranges from 7.2 to 10.0 degrees C (45 to 50 degrees F).

GEOGRAPHICALLY ASSOCIATED SOILS: Thomas soils are associated in the landscape with Parkhill soils. Parkhill soils lack the organic surface layer that is present in the Thomas soils.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Poorly drained or very poorly drained. Potential for surface runoff is negligible. Saturated hydraulic conductivity is moderately low or moderately high. Permeability is slow or moderately slow.

USE AND VEGETATION: Most areas of this soil are used for pasture or are in woodland. A few small areas are used for the production of corn, small grain and hay.

DISTRIBUTION AND EXTENT: MLRAs 96, 98, and 99 in lower Michigan. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: AMHERST, MASSACHUSETTS

SERIES ESTABLISHED: Tuscola County, Michigan, 1926.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Histic epipedon: from the surface to a depth of 23 cm (9 inches) (Oap horizon).
Cambic horizon: from a depth of 23 to 43 cm (9 to 17 inches) (Bg horizon).
Aquic conditions: redoximorphic features present in all mineral horizons below the histic epipedon.

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National Cooperative Soil Survey
U.S.A.