LOCATION SALMO                   SD+NE

Established Series
Rev. WFJ-WJB
03/2020

SALMO SERIES


The Salmo series consists of very deep, somewhat poorly drained and poorly drained soils formed in silty alluvium on flood plains. Permeability is moderate or moderately slow in the solum and moderately slow or slow in the underlying material. Slopes are less than 1 percent. Mean annual precipitation is about 23 inches, and mean annual temperature is about 47 degrees F.

TAXONOMIC CLASS: Fine-silty, mixed, superactive, calcareous, mesic Cumulic Endoaquolls

TYPICAL PEDON: Salmo silt loam - on a plane, less than 1 percent slope in native pasture. When described the soil was moist throughout. (Colors are for moist soil unless otherwise stated.)

Az--0 to 5 inches; black (10YR 2/1) silt loam, very dark gray (10YR 3/1) dry; weak fine granular structure; slightly hard, friable, slightly sticky; very few fine accumulations of salt; slight effervescence; moderately alkaline; clear wavy boundary. (3 to 15 inches thick)

Bz1--5 to 10 inches; black (10YR 2/1) silt loam, dark gray (10YR 4/1) dry; weak medium prismatic structure parting to weak medium and fine subangular blocky; hard, friable, slightly sticky; many fine segregations of salt; few fine accumulations of gypsum; strong effervescence; moderately alkaline; clear wavy boundary.

Bz2--10 to 24 inches; black (10YR 2/1) silt loam, dark gray (10YR 4/1) dry; weak medium prismatic structure parting to weak medium and fine subangular blocky; hard, friable, slightly sticky; many fine accumulations of salt; common nests and crystals of gypsum; violent effervescence; moderately alkaline; clear wavy boundary. (Combined Bz horizons is 10 to 30 inches thick.)

Bkyg1--24 to 32 inches; very dark grayish brown (2.5Y 3/2) silt loam, grayish brown (2.5Y 5/2) dry; common medium faint light olive brown (2.5Y 5/6) mottles; weak coarse and medium subangular blocky structure; very hard, friable, slightly sticky; many nests and crystals of gypsum and other salts; few fine accumulations of carbonates; violent effervescence; slightly alkaline; gradual wavy boundary. (0 to 14 inches thick)

Bkyg2--32 to 47 inches; dark grayish brown (2.5Y 4/2) silt loam, grayish brown (2.5Y 5/2) dry; few streaks of very dark grayish brown (2.5Y 3/2); common fine and medium distinct light olive brown (2.5Y 5/6) mottles; weak coarse subangular blocky structure; very hard, friable, slightly sticky; many nests and crystals of gypsum and other salts; common fine accumulations of carbonates; violent effervescence; slightly alkaline; clear wavy boundary. (0 to 15 inches thick)

Cg--47 to 60 inches; dark grayish brown (2.5Y 4/2) silty clay loam, grayish brown (2.5Y 5/2) dry; common fine and medium distinct light olive brown (2.5Y 5/6) mottles; massive; very hard, friable, slightly sticky; violent effervescence; moderately alkaline.

TYPE LOCATION: Davison County, South Dakota; about 1 mile east and 4 miles south of Mount Vernon; 530 feet south and 1,285 feet west of the northeast corner, sec. 14, T. 102 N., R. 62 W.

RANGE IN CHARACTERISTICS: The series control section typically is silt loam, but is silty clay loam in some pedons. Thickness of mollic epipedon ranges from 24 to more than 60 inches. Greatest accumulations of salts other than gypsum typically are in the A horizon. Electrical conductivity of the saturation extract ranges from 4 to 16 mmhos in the upper 20 inches and from 3 to 10 mmhos or more below depths of 20 inches. The soil typically has a Bz horizon in the upper B horizon and a Bk horizon in the lower part.

The A horizon has 10YR, 2.5Y, and 5Y hue, or is neutral, value of 2 or 3 and 3 or 4 dry, and chroma of 1 or less. It is silt loam or silty clay loam and ranges from neutral to moderately alkaline.

The B horizon is neutral or has hue of 10YR, 2.5Y, or 5Y; value of 2 to 4 and 3 to 6 dry; and chroma of 0 to 2. It typically has few to common distinct and prominent mottles in the lower part. It is silt loam or silty clay loam. It typically has the greatest amount of salts in the upper part (Bz horizon) and the content decreases with depth. Accumulations of carbonates and gypsum typically are greatest in the lower part (Bk and Bky horizon). It ranges from neutral to moderately alkaline. Some pedons have Byz or Byg horizons.

The Cg horizon is neutral or is 2.5Y or 5Y hue, value of 2 to 5 and 3 to 7 dry, and chroma of 0 to 2. It typically has few to many medium distinct or prominent mottles, however, some pedons lack mottles but have matrix chroma of 1 or less. It is silt loam or silty clay loam. It ranges from neutral to moderately alkaline. Crystals and nests of gypsum and other salts in the Cg horizon range widely in size and amount. The Cg horizon below depths of 40 inches commonly is silty clay loam, clay loam, or silty clay, but some pedons contain strata of loam or silt loam. Loose sand and gravel are at depths of 40 to 60 inches in some pedons.

COMPETING SERIES: These are the Badus, Calco, Devilsgait, Lamo, Obert, and Wingdale series in the same family. Badus, Calco, Devilsgait, Lamo, Obert, and Wingdale soils contain less visible salts throughout. In addition, Devilsgait, and Wingdale soils are drier in the soil moisture control section in May and June.

GEOGRAPHIC SETTING: Salmo soils are on level flood plains that have higher water tables. Slope gradients are less than 1 percent. The soils formed in silty alluvium. Climate is subhumid. Mean annual temperature ranges from 45 to 52 degrees F, and mean annual precipitation ranges from 18 to 26 inches.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing Lamo soils and the Alcester, Bon, and Clamo soils. Lamo and Clamo soils are on similar landscapes. Clamo soils contain more clay in the control section. Alcester and Bon soils are better drained and on higher positions. Alcester soils are leached of carbonates to greater depths and do not have visible salts.

DRAINAGE AND PERMEABILITY: Poorly drained and somewhat poorly drained. Surface runoff is slow or very slow. Permeability is moderate or moderately slow in the solum and moderately slow or slow in the underlying material. The water table is near the surface in the spring and at depths of 2 to 4 feet in the fall. Salmo soils are flooded during periods of above average rainfall.

USE AND VEGETATION: Mostly used for pasture and hay. Native grasses are cordgrass, switchgrass, western wheatgrass, and sedges.

DISTRIBUTION AND EXTENT: Southeastern South Dakota and possibly eastern Nebraska. The series is of moderate extent.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: SALINA, KANSAS

SERIES ESTABLISHED: Davison County, South Dakota, 1970.

REMARKS: Diagnostic horizons and features recognized in this pedon are: mollic epipedon - the zone from the surface of the soil to a depth of about 32 inches (Az, Bz1, Bz2, Bkyg1 horizons); zone of salt accumulation - the zone from the surface of the soil to a depth of about 24 inches (Az, Bz, Bz2 horizons).


National Cooperative Soil Survey
U.S.A.