LOCATION MINATARE NE+SDEstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, mesic Aquic Natrustalfs
TYPICAL PEDON: Minatare silt loam with a slope of less than 1 percent in rangeland. When described, the soil was moist throughout. (Colors are for dry soil unless otherwise stated.)
A--0 to 1 1/2 inches; gray (10YR 5/1) silt loam, very dark gray (10YR 3/1) moist; weak medium granular structure; soft, friable; exchangeable sodium percentage = 5; slightly alkaline; abrupt smooth boundary. (1 to 5 inches thick)
E--1 1/2 to 3 inches; light gray (10YR 7/1) loam, gray (10YR 5/1) moist; weak fine platy structure; soft, friable; exchangeable sodium percentage = 24; strongly alkaline; abrupt wavy boundary. (1 to 3 inches)
Btn1--3 to 7 inches; light brownish gray (10YR 6/2) clay loam, dark grayish brown (10YR 4/2) moist; moderate medium columnar structure parting to weak medium subangular blocky; hard, firm, sticky; exchangeable sodium percentage = 94; few thin films on faces of peds; violent effervescence; very strongly alkaline; clear smooth boundary.
Btn2--7 to 20 inches; light brownish gray (10YR 6/2) clay, dark grayish brown (10YR 4/2) moist; weak medium columnar structure parting to weak medium subangular blocky; very hard, very sticky; exchangeable sodium percentage = 96; common thin films on faces of peds; violent effervescence; very strongly alkaline; clear smooth boundary. (Combined thickness of Bt horizon is 16 to 30 inches thick.)
Bkn1--20 to 26 inches; light gray (10YR 7/2) clay loam, grayish brown (10YR 5/2) moist; weak medium subangular blocky structure; hard, firm, sticky; exchangeable sodium percentage = 110; few soft masses and fine concretions of carbonates; violent effervescence; very strongly alkaline; clear smooth boundary.
Bkn2--26 to 33 inches; light gray (10YR 7/2) clay loam, grayish brown (10YR 5/2) moist; few common reddish brown iron masses (5YR 4/4 moist) in the matrix in the lower part; moderate medium subangular blocky structure; very hard, very firm; exchangeable sodium percentahe = 76; few soft masses and fine concretions of carbonates; violent effervescence; very strongly alkaline; abrupt, wavy boundary.
2Cg--33 to 40 inches; light olive gray (5Y 6/2) gravelly coarse sandy loam, olive gray (5Y 4/2) moist, common medium prominent reddish brown (5YR 4/4 moist) iron masses in the matrix; massive; slightly hard, firm; exchangeable sodium percentage = 76; very strongly alkaline; clear wavy boundary. (0 to 10 inches thick)
2C--40 to 60 inches; very pale brown (10YR 7/3) very gravelly coarse sand, brown (10YR 5/3) moist; common, medium distinct yellowish brown (10YR 5/6 moist) iron masses in the matrix in the upper part; single grain; loose, very strongly alkaline.
TYPE LOCATION: Scotts Bluff County, Nebraska; about 1 mile north and 2 1/2 miles east of McGrew; 600 feet west and 200 feet north of the southeast corner of sec. 29, T. 21 N., R. 52 W.
RANGE IN CHARACTERISTICS: Thickness of the solum ranges from 18 to 38 inches. Depth to free carbonates ranges from 0 to 8 inches.
The A horizon has hue of 10YR or 2.5Y, value of 5 through 7 and 3 through 5 moist, and chroma of 1 or 2. It is typically silt loam with the range including loam, very fine sandy loam, and fine sandy loam. Where the soil has been cultivated, it commonly has a calcareous clay loam Ap horizon. Reaction ranges from slightly to very strongly alkaline. Exchangeable sodium percentage ranges from 0 to 9. Electrical conductivity (mmhos/cm) is less than 2.
The Btn horizon has hue of 10YR or 2.5Y, value of 4 through 6 and 3 through 5 moist, with chroma of 2 or 3. It is clay loam, silty clay, or clay averaging between 35 and 50 percent clay. The sodium absorption ratio is 13 or more and the exchangeable sodium percentage is 15 or more. Electrical conductivity ranges from 4 to 30.
The Bkn horizon has hue of 10YR or 2.5Y, value of 6 through 8 and 4 through 6 moist, and chroma of 1 or 2. Texture is typically clay loam with the range including loam, silty clay loam, and sandy clay loam. Some pedons have a C horizon. Sodium adsorption ratio is 13 or more and exchangeable sodium percentage is 15 or more. Reaction is strongly alkaline or very strongly alkaline.
The 2Cg horizon is a gleyed layer with hue of 5Y or other gleyed colors. The texture ranges from gravelly coarse sandy loam to silt loam. This horizon is absent in some pedons.
The lower 2C horizon has hue of 7.5YR, 10YR or 2.5Y; value of 5 through 8 and 6 through 7 moist; and chroma of 2 through 4. Colors are those of the minerals in the sands and gravels. The texture is typically very gravelly coarse sand with the range including coarse sand and gravelly coarse sand. Thin strata of loamy sand and sand are in some pedons. In places, silty, loamy, and clayey alluvium is at a depth of 40 to below 60 inches. Reaction is strongly or very strongly alkaline.
COMPETING SERIES: Minatare is the only series in the family. Similar soils in closely related families are the Arvada, Janise, Jankosh, Napa, Saltine, and Zoe soils. Arvada soils are better drained and are in the montmorillonitic minerology class. Janise and Jankosh soils are coarse-silty. Napa soils are poorly drained, have a mollic epipedon, and are in an area of greater precipitation. Saltine soils are fine-silty and do not have an argillic horizon. Zoe soils are in the montmorillonitic minerology class and do not have an argillic horizon.
GEOGRAPHIC SETTING: Minatare soils are on flood plains. They formed in loamy and clayey textured alluvium containing much sodium and in places, soluble salts. Slopes range from 0 to 2 percent. The mean annual precipitation ranges from 14 to 18 inches and the mean annual temperature ranges from 45 to 51 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Janise soils and the alkali phases of the Gering, McGrew, and Yockey soils. All associated soils are higher on the landscape. Gering and McGrew soils do not have an argillic horizon and contain less sodium. In addition, Gering soils are fine-loamy over sandy or sandy skeletal and McGrew soils are coarse-loamy. Yockey soils are coarse-silty.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Permeability is very slow. Runoff is low. The seasonal high water table ranges from a depth of 1 to 3 feet. During midsummer it commonly recedes to a depth of 3 to 5 feet. (See Remarks). Flooding is rare or occasional and for brief durations.
USE AND VEGETATION: Nearly all areas are in native grass and used for rangeland or hayland. Inland saltgrass, alkali sacaton, and western wheatgrass are the principal species. A few areas of this soil are cultivated, but yields are generally poor.
DISTRIBUTION AND EXTENT: Western Nebraska and southwestern South Dakota. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Scotts Bluff County, Nebraska, 1913.
ADDITIONAL DATA: Laboratory data for the typical pedon of Minatare silt loam is available as sample numbers S62Neb-79-4(1-8) and Nebraska State Highway sample numbers S61-6473 to 6475.
REMARKS: Diagnostic horizons and other features recognized in this pedon are: ochric epipedon--the zone from 0 to 3 inches (A and E horizon); natric horizon--the zone from 3 to 20 inches (Btn1 and Btn2 horizon) and aquic soil conditions--saturation and redox features at depths less than 30 inches. The water table at the type location was observed at 39 inches on July 11, 1962. Series reclassified from Aquic Natrargids to Aquic Natrustalfs.