LOCATION SHAMBO                  ND+MT SD

Established Series
ARG-CJH
01/2023

SHAMBO SERIES


The Shambo series consists of deep and very deep, well drained, moderately permeable soils that formed in calcareous alluvium mainly from soft sandstone, mudstone and shale. These soils are on terraces and fans along stream valleys and are on fans on uplands. Slope ranges from 0 to 35 percent. Mean annual air temperature is 42 degrees F, and mean annual precipitation is 15 inches.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Typic Haplustolls

TYPICAL PEDON: Shambo loam - on a convex, gently sloping upland fan on 4 percent slope in tame pasture. (Colors are for dry soil unless otherwise stated)

Ap--0 to 9 inches; dark grayish brown (10YR 4/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine roots; neutral; abrupt smooth boundary. (Combined A horizons 4 to 9 inches thick)

Bw1--9 to 13 inches; brown (10YR 4/3) loam, very dark grayish brown (10YR 3/2) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; neutral; clear wavy boundary.

Bw2--13 to 20 inches; brown (10YR 5/3) loam, dark grayish brown (10YR 4/2) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common fine roots, slightly alkaline; gradual wavy boundary.

Bw3--20 to 29 inches; light olive brown (2.5Y 5/4) loam, dark grayish brown (2.5Y 4/2) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common fine roots; slightly alkaline; clear wavy boundary. (Combined Bw horizons 9 to 24 inches thick)

Bk--29 to 42 inches; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; weak coarse prismatic structure parting to weak medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; few fine roots; strong effervescence; moderately alkaline; gradual smooth boundary. (6 to 32 inches thick)

BCk--42 to 48 inches; light gray (2.5Y 7/2) loam, light brownish gray (2.5Y 6/2) moist; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; strong effervescence; moderately alkaline; gradual smooth boundary.

C--48 to 60 inches; light gray (2.5Y 7/2) loam, light yellowish brown (2.5Y 6/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; strong effervescence; moderately alkaline.

TYPE LOCATION: Grant County, North Dakota; about 1800 feet south and 1150 feet east of the northwest corner of Sec. 27, T. 131 N., R. 90 W.

RANGE IN CHARACTERISTICS: Depth to carbonates ranges from 10 to 35 inches. The mollic epipedon ranges from 7 to 16 inches in thickness and commonly includes the upper part of the Bw horizon. Some pedons have an Ab horizon.

The A horizon has hue of 10YR, value of 3 to 5 and 2 or 3 moist, and chroma of 2 or 3. It is loam, silt loam, clay loam or fine sandy loam. It is slightly acid to slightly alkaline.

The Bw horizon has hue of 10YR or 2.5Y, value of 4 to 6 and 3 to 5 moist, and chroma of 2 to 4. It is loam, silt loam or clay loam, and typically averages 15 to 45 percent fine sand and coarser. It commonly has moderate or strong grades of prismatic and blocky structure. It is neutral to moderately alkaline.

The Bk horizon has hue of 10YR, 2.5Y or 5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is loam, clay loam, silty clay loam or silt loam. It is slightly alkaline or moderately alkaline. It has disseminated and few to many masses of carbonates. Calcium carbonate equivalent ranges from 5 to 20 percent. Some pedons do not have a BCk horizon.

The C horizon has hue of 10YR, 2.5Y or 5Y, value of 5 to 7 and 4 to 6 moist, and chroma of 2 to 4. It is loam, or is stratified with sandy loam, fine sandy loam, very fine sandy loam, silty clay loam, sandy clay loam and clay loam. It is slightly alkaline or moderately alkaline.

The 2C horizon, where present, occurs at depths of more than 40 inches. It has hue of 7.5YR to 5Y, value of 6 and 4 or 5 moist, and chroma of 2 to 4. It is loamy fine sand, gravelly loam or gravelly sandy loam. It is slightly alkaline to strongly alkaline. Some pedons have a Cr horizon of soft bedrock below a depth of 40 inches. It has hue of 5Y, value of 6 or 7 and 5 or 6 moist and chroma of 2 or 3.

COMPETING SERIES: These are the Amor, Azaar, Diagulch, Max, Peerless, Quigley, Tansem, Tewfel and Twin Creek series. Amor, Azaar and Tewfel soils have soft bedrock within depths of 20 to 40 inches. Diagulch soils have a calcic horizon and do not have a cambic horizon. Max soils have rock fragments throughout. Peerless soils have more than 35 percent rock fragments within a depth of 40 inches. Quigley soils have 2 to 30 percent by volume of rock fragments and calcic horizons within depths of 15 to 20 inches. Tansem soils have more silt, have calcic horizons with 20 to 30 percent calcium carbonate equivalent and, in addition, formed in glacial lake sediments. Twin Creek soils have hue of 5YR or 7.5YR throughout and formed in calcareous reddish colored alluvium.

GEOGRAPHIC SETTING: Shambo soils are on level to steep terraces and fans along stream valleys and on fans on uplands. Slope gradients mainly are less than 6 percent, but range from 0 to 35 percent. The soils formed in calcareous alluvium derived mainly from soft sandstone, mudstone and shale sedimentary beds. The mean annual air temperature ranges from 39 to 45 degrees F, and the mean annual precipitation from 13 to 19 inches. Mean annual precipitation ranges up to 20 inches in the foothills of the mountains.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Amor soils and the Arnegard, Belfield, Farland, Korchea, Morton, Parshall, Reeder, Regent, Rhoades, Wyola, Sen, Stady, Straw, Tally and Vebar soils. Amor, Morton, Reeder, Sen and Vebar soils are on nearby uplands. They are moderately deep to soft bedrock. Arnegard soils are on nearby swales and concave fans. They have a mollic epipedon more than 16 inches thick. Farland, Parshall, Stady and Tally soils are on nearby terraces. Farland soils are fine-silty; Parshall and Tally soils coarse-loamy; and Stady soils fine-loamy over sandy or sandy-skeletal. Korchea and Straw soils are on lower lying terraces and flood plains. They have an irregular decrease in organic carbon with depth. Belfield and Rhoades soils are on nearby terraces and uplands. They have natric horizons. Regent soils are on uplands and Wyola soils are on nearby terraces. They are fine.

DRAINAGE AND PERMEABILITY: Well drained. Runoff is negligible to high depending on slope and surface texture. Permeability is moderate.

USE AND VEGETATION: Soils are cropped to small grains, hay and pasture. Some is irrigated and some are in native rangeland. Native vegetation was green needlegrass, needleandthread, western wheatgrass, prairie junegrass, blue grama and a variety of forbs.

DISTRIBUTION AND EXTENT: Western North Dakota, eastern Montana and northwestern South Dakota. The soil is of large extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Salina, Kansas

SERIES ESTABLISHED: Bowman County, North Dakota, 1969.

REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - zone from the surface of the soil to a depth of 13 inches (Ap and Bw1 horizons); cambic horizon - zone from 13 to 29 inches (Bw2 and Bw3 horizons).


National Cooperative Soil Survey
U.S.A.