LOCATION STADY              ND+CO MT SD
Established Series
CJH
09/2005

STADY SERIES


The Stady series consists of very deep, well drained soils moderately deep to sand and gravel. Permeability is moderate in the upper horizons and very rapid in the 2Bk and 2C horizons. These soils formed in loamy alluvium over sand and gravel and are on stream terraces. Slopes are 0 to 9 percent. Mean annual air temperature is 42 degrees F, and mean annual precipitation is 15 inches.

TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, frigid Typic Haplustolls

TYPICAL PEDON: Stady loam - cultivated. (Colors for dry soil unless otherwise stated)

Ap--0 to 6 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; friable; many roots and very fine pores; neutral; abrupt smooth boundary. (5 to 10 inches thick)

Bw1--6 to 12 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; strong coarse prismatic and moderate medium subangular blocky structure; friable; common roots, common very fine pores; faint clay films on prism faces; neutral; gradual smooth boundary.

Bw2--12 to 15 inches; grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; moderate coarse prismatic structure; friable; few roots; common very fine pores; neutral; clear wavy boundary. (Combined Bw horizons 7 to 14 inches thick)

Bk1--15 to 18 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; weak coarse prismatic and moderate coarse and medium subangular blocky structure; friable; few roots; disseminated carbonates throughout; strong effervescence; slightly alkaline; clear wavy boundary.

Bk2--18 to 29 inches; light brownish gray (2.5Y 6/2) loam, dark grayish brown (2.5Y 4/2) moist; weak coarse prismatic and weak coarse subangular blocky structure; friable; few roots; few stones; common carbonate masses; violent effervescence; moderately alkaline; clear wavy boundary. (Combined Bk horizons 3 to 25 inches thick)

2Bk3--29 to 42 inches; light brownish gray (2.5Y 6/2) sand and gravel, grayish brown (2.5Y 5/2) moist; single grain; loose; thin carbonate crusts coat bottom of all pebbles; violent effervescence; moderately alkaline, gradual boundary. (0 to 40 inches thick)

2C--42 to 60 inches; light yellowish brown (10YR 6/4) sand and gravel, dark yellowish brown (10YR 4/4) moist; single grain; loose; strong effervescence; moderately alkaline.

TYPE LOCATION: Slope County, North Dakota; 220 feet north and 115 feet east of the southwest corner, sec. 35, T. 133 N., R. 100 W.

RANGE IN CHARACTERISTICS: A few pebbles and an occasional stone are in the A and Bw horizons. The depth to sand and gravel ranges from 20 to 40 inches and depth to carbonates ranges from 15 to 25 inches.

The A horizon has hue of 10YR, value of 3 to 5 and 2 or 3 moist, and chroma of 2. It is loam or silt loam. It is neutral.

The Bw horizon has hue of 10YR, value of 4 to 6 and 2 to 4 moist, and chroma of 2 to 4. It is loam and neutral or slightly alkaline. There are faint clay films on faces of peds and a slight clay increase in the Bw horizon in some pedons. It has strong or moderate coarse or medium prismatic structure parting to strong or moderate angular and subangular blocky structure.

The Bk horizon has hue of 10YR or 2.5Y, value of 6 or 7 and 4 or 5 moist, and chroma of 2 to 4. It is loam or gravelly loam and has weak or moderate structure. It is slightly alkaline or moderately alkaline.

The 2Bk and 2C horizons have hue of 10YR or 2.5Y, value of 5 or 6 and 4 or 5 moist, and chroma of 2 to 4. They are slightly alkaline or moderately alkaline. They have a wide range in size and amount of gravel and sand. Much of the sand and gravel is from sedimentary rocks.

COMPETING SERIES: This is the Lehr series. Lehr soils have sandy or sandy-skeletal materials at depths of less than 20 inches.

GEOGRAPHIC SETTING: Stady soils are on level to moderately sloping stream terraces. Slopes are mainly l to 4 percent but range from 0 to 9 percent. Stady soils formed in loamy alluvium over sand and gravel. The climate is semiarid with a mean annual air temperature of 34 to 45 degrees F, and the mean annual precipitation of 12 to 18 inches. Three-fourths of the precipitation falls in the spring and summer.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Lehr soils and the Farland, Manning, Parshall, Shambo, Tally and Wabek soils. Lehr and Shambo soils are on similar landscapes. Shambo soils do not have gravelly 2C horizons within depths of 40 inches. Farland, Manning, Parshall, Tally and Wabek soils are on nearby terraces but commonly at a different level. Farland soils are fine-silty and have an argillic horizon. Manning soils are coarse-loamy above the 2C material. Parshall soils have mollic epipedons thicker than 16 inches and are coarse-loamy. Tally soils have sandy loam textures and do not have 2C horizons. Wabek soils do not have Bw horizons, typically are less than 10 inches thick over 2C horizons, and are sandy-skeletal.

DRAINAGE AND PERMEABILITY: Well drained. Runoff is negligible to low depending on slope. Permeability is moderate in the upper horizons and very rapid in the 2Bk and 2C horizons.

USE AND VEGETATION: Soils are cropped to spring wheat, other small grains, and corn. Some areas are used for hay and pasture. Native vegetation is mid and short prairie grasses including green needlegrass, western wheatgrass, and blue grama, and also perennial legumes.

DISTRIBUTION AND EXTENT: Residual plains of western North Dakota and northwestern South Dakota, mostly west and south of the Missouri River in MLRA 54. The soil is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado

SERIES ESTABLISHED: Bowman County, North Dakota, 1969.

REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of 12 inches (Ap and Bw1 horizons); The zone from 12 to 15 inches (Bw2 horizon) meets the requirements for a cambic horizon except for thickness.

The intent is for the series to be used in association with residual landforms. Where it has been previously correlated in association with glacial landforms it will be recorrelated to Bowdle in the future.


National Cooperative Soil Survey
U.S.A.