LOCATION PETA               ND 
Established Series
TMC-ARG-CJH
11/2003

PETA SERIES


The Peta series consists of very deep, somewhat poorly drained soils that formed in alluvium. Permeability is moderate. These soils are on alluvial flats. Slopes are 0 to 3 percent. Mean annual precipitation is about 15 inches, and mean annual air temperature is 42 degrees F.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aquic Argiustolls

TYPICAL PEDON: Peta loam, cultivated (Colors are for dry soil unless otherwise stated. When described the soil was dry throughout.)

Ap--0 to 5 inches; very dark grayish brown (10YR 3/2) loam, very dark brown (10YR 2/2) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; 18 percent clay; neutral; clear smooth boundary.

A--5 to 10 inches; very dark grayish brown (10YR 3/2) loam, very dark brown (10YR 2/2) moist; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots throughout; common very fine tubular pores; 18 percent clay; neutral; clear smooth boundary. (Combined A horizons 4 to 16 inches thick)

Bt1--10 to 20 inches; brown (10YR 4/3) loam, dark brown (10YR 3/3) moist; weak medium prismatic structure parting to moderate medium subangular blocky; moderately hard, friable, slightly sticky and slightly plastic; common very fine roots throughout; common very fine tubular pores; 25 percent clay; few distinct discontinuous very dark grayish brown (10YR 3/2) moist, clay films throughout; common fine rounded distinct dark yellowish brown (10YR 4/6) redoximorphic concentrations from 16 to 20 inches; neutral; clear wavy boundary.

Bt2--20 to 26 inches; light olive brown (2.5Y 5/4) clay loam, olive brown (2.5Y 4/4) moist; weak medium prismatic structure parting to moderate medium subangular blocky; moderately hard, friable, slightly sticky and slightly plastic; common very fine roots throughout; common very fine tubular pores; 23 percent clay; few distinct discontinuous dark brown (10YR 3/3) moist, clay films throughout; common fine rounded prominent strong brown (7.5YR 4/6) redoximorphic concentrations throughout; neutral; clear wavy boundary. (Combined Bt horizons 9 to 23 inches thick)

BC--26 to 36 inches; light olive brown (2.5Y 5/4) fine sandy loam, olive brown (2.5Y 4/4) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and nonplastic; common very fine roots throughout; common very fine tubular pores; 15 percent clay; common fine rounded prominent strong brown (7.5YR 4/6) redoximorphic concentrations throughout; neutral; gradual wavy boundary. (0 to 20 inches thick)

C1--36 to 48 inches; light olive brown (2.5Y 5/4) fine sandy loam, olive brown (2.5Y 4/4) moist; massive; slightly hard, very friable, slightly sticky and nonplastic; few very fine roots throughout; common very fine tubular pores; 11 percent clay; common fine rounded prominent strong brown (7.5YR 4/6) redoximorphic concentrations throughout and common fine rounded prominent light olive gray (5Y 6/2) redoximorphic depletions throughout; slightly alkaline; gradual wavy boundary.

C2--48 to 53 inches; light yellowish brown (2.5Y 6/3) loam, light olive brown (2.5Y 5/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots throughout; 18 percent clay; common fine rounded prominent strong brown (7.5YR 4/6) redoximorphic concentrations throughout and common fine rounded distinct light olive gray (5Y 6/2) redoximorphic depletions throughout; common fine rounded masses of lime pedogenic throughout; strongly effervescent (HCL, 1 normal); moderately alkaline; gradual wavy boundary.

C3--53 to 80 inches; light brownish gray (2.5Y 6/2) fine sandy loam, grayish brown (2.5Y 5/2) moist; massive; soft, very friable, slightly sticky and nonplastic; 9 percent clay; common fine rounded prominent strong brown (7.5YR 4/6) redoximorphic concentrations throughout; slightly effervescent (HCL, 1 normal); moderately alkaline.

TYPE LOCATION: Billings County, North Dakota; 2,150 feet east and 1,900 feet south of the northwest corner of sec. 23, T. 142 N., R. 99 W.

RANGE IN CHARACTERISTICS:

Soil temperature - 40 to 45 degrees F.

Mollic thickness - 16 to 40 inches.

Depth to redoximorphic features - 7 to 32 inches.

Percent rock fragments - less than 1 percent

A horizon - Hue 10YR

Value: 3 or 4, (2 or 3 moist)

Chroma: 1 to 3

Texture: loam, fine sandy loam

Reaction - slightly acid or neutral

Bt horizon - Hue 10YR or 2.5Y

Value: 4 or 5, (3 or 4 moist)

Chroma: 2 to 4

Texture: loam, clay loam or sandy clay loam

Percent clay - average 22 to 30

Redoximorphic features:
Hue 10YR, 2.5Y or 7.5YR
Value: 4 or 5
Chroma: 2 to 6

Reaction - neutral or slightly alkaline

Some pedons have a Bw horizon above or below the Bt horizon

BC horizon - Hue 2.5Y or 10YR

Value: 5 or 6 (4 or 5 moist)

Chroma: 2 to 4

Texture: fine sandy loam, sandy loam or sandy clay loam

Redoximorphic features:
Hue 2.5Y, 7.5YR, 5Y, or 10YR
Value: 4 to 6
Chroma: 2 to 6

Reaction - neutral or slightly alkaline

Some pedons have a Bk or BCk horizon

C horizon - Hue 2.5Y, 5Y or 10YR

Value: 5 to 7 (4 or 5 moist)

Chroma: 2 to 4

Texture: fine sandy loam, loam, sandy loam or loamy sand

Redoximorphic features:
Hue 7.5YR, 2.5Y, 5Y, or 10YR
Value: 4 to 6
Chroma: 1 to 6

Reaction - slightly alkaline or moderately alkaline

COMPETING SERIES:

Center Creek: Have a 2C horizon with more than 35 percent rock fragments.

GEOGRAPHIC SETTING:

Landform - alluvial flats.

Elevation - 2,000 to 3,000 feet.

Slope- 0 to 3 percent.

Parent material - alluvium.

Climate - cool, with long, cold winters; moist springs; warm summers.

Mean annual precipitation - 14 to 16 inches.

Mean annual air temperature - 40 to 45 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Amor, Lehr, Parshall, Reeder, Regent, Tally and Wabek soils. Amor and Reeder soils are on side slopes of uplands. Regent soils are on upland plains. Amor, Reeder and Regent soils have soft bedrock at a depth of 20 to 40 inches. Lehr and Wabek soils are on outwash plains and dissected terraces. They have gravel within 20 inches of the surface. Parshall and Tally soils are on similar landscapes, but have less than 18 percent clay in the particle-size control section.

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Moderate permeability. The soil has a seasonal high water table at depths of 2 to 4 feet at some time during the period of April through June.

USE AND VEGETATION: Most areas are used as cropland. Some areas are used for range. The potential native plant community is mainly big bluestem, switchgrass, western wheatgrass, and green needlegrass.

DISTRIBUTION AND EXTENT: Southwestern North Dakota. Peta soils are of small extent.

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

SERIES ESTABLISHED: Billings County, North Dakota, 1998.

REMARKS: Diagnostic horizons and features recognized in this pedon: mollic epipedon - the zone from the surface of the soil to a depth of 20 inches (Ap, A and Bt1 horizons); argillic horizon - the zone from 10 to 26 inches (Bt1 and Bt2 horizons).


National Cooperative Soil Survey
U.S.A.