LOCATION WILDHORSE          NE+SD
Established Series
Rev. LGR, RRH
08/2009

WILDHORSE SERIES


The Wildhorse series consists of very deep, somewhat poorly drained soils that formed in eolian sand on swales and hummocks on interdunes on sandhills of the Nebraska Sandhills (MLRA 65). Slopes range from 0 to 3 percent. Mean annual precipitation is about 41 centimeters (16 inches), and mean annual air temperature is about 8 degrees C. (47 degrees F.) at the type location.

TAXONOMIC CLASS: Sandy, mixed, mesic Typic Halaquepts

TYPICAL PEDON: Wildhorse sand with a 1 percent nearly level slope in rangeland (native hay). (When described, the soil was moist in the upper 64 centimeters (25 inches) and wet below. Colors are for moist soils unless otherwise stated.)

A--0 to 10 centimeters (0 to 4 inches); very dark grayish brown (10YR 3/2) sand, grayish brown (10YR 5/2) dry; weak very fine granular structure; very friable, slightly hard; common fine roots; exchangeable sodium percentage = 20; sodium adsorption ratio = 12; slight effervescence; very strongly alkaline; abrupt smooth boundary. (8 to 25 centimeters (3 to 10 inches) thick)

AC1--10 to 18 centimeters (4 to 7 inches); dark grayish brown (10YR 4/2) sand, light brownish gray (10YR 6/2) dry; weak fine granular structure; very friable, slightly hard; few fine roots; exchangeable sodium percentage = 49; sodium adsorption ratio = 27; electrical conductivity = 3; slight effervescence; very strongly alkaline; clear smooth boundary.

AC2--18 to 25 centimeters (7 to 10 inches); dark grayish brown (10YR 4/2) sand, light brownish gray (10YR 6/2) dry; weak fine granular structure; very friable, soft; few fine roots; exchangeable sodium percentage = 56; sodium adsorption ratio = 28; electrical conductivity = 3; strong effervescence; very strongly alkaline; clear smooth boundary. (0 to 28 centimeters [Combined thickness of the AC horizon is 0 to 28 centimeters (0 to 11 inches thick) 0 to 11 inches) thick]

C--25 to 43 centimeters (10 to 17 inches); grayish brown (10YR 5/2) sand, light brownish gray (10YR 6/2) dry; single grain, loose; few fine roots; exchangeable sodium percentage = 48; sodium adsorption ratio = 22; electrical conductivity = 2; strong effervescence; very strongly alkaline; gradual smooth boundary.

Cg1--43 to 64 centimeters (17 to 25 inches); grayish brown (10YR 5/2) sand, light brownish gray (10YR 6/2) dry; few fine faint yellowish brown (10YR 5/4) moist iron masses in the matrix; single grain; loose; few fine roots; exchangeable sodium percentage= 8; sodium adsorption ratio= 6; strong effervescence; very strongly alkaline; clear smooth boundary

Cg2--64 to 89 centimeters (25 to 35 inches); grayish brown (2.5Y 5/2) sand, light gray (10YR 7/2) dry; few fine faint yellowish brown (10YR 5/4) moist iron masses in the matrix; single grain; loose; few fine roots; violent effervescence; strongly alkaline; gradual smooth boundary.

Cg3--89 to 200 centimeters (35 to 79 inches); grayish brown (2.5Y 5/2) fine sand, light gray (10YR 7/2) dry; few fine distinct yellowish brown (10YR 5/4) moist iron masses in the matrix; single grain; loose; slight effervescence; strongly alkaline.

TYPE LOCATION: Morrill County, Nebraska; about 38 kilometers (24 miles) north and 6 kilometers (4 miles) east of Broadwater; 213 meters (700 feet) east and 244 meters (800 feet) north of the southwest corner of sec. 27, T. 23 N., R. 47 W.

RANGE IN CHARACTERISTICS:
Soil moisture: aquic
Soil temperature: mesic
Depth of Carbonates: typically 0 to 200 centimeters (0 to 79 inches),
Depth to redoximorphic features: 46 to 91 centimeters (18 to 36 inches)
Depth to endosaturation: 46 to 91 centimeters (18 to 36 inches)
Exchangeable sodium percentage: 15 or more
Sodium adsorption ratio: 13 or more,
ESP (or SAR) values: decreases with increasing depth below 51 centimeters (20 inches) of the surface
Particle-size control section (weighted average):
Clay content: 1 to 10 percent
Sand content: 78 to 99 percent

A horizon or Ak when present:
Hue: 10YR or 2.5Y
Value: 4 to 6, 3 to 5 moist
Chroma: 1 or 2
Texture: typically sand but including fine sand, loamy sand, and loamy fine sand
Sodium adsorption ratio (SAR): 6 to 105
Exchangeable sodium percentage (ESP): 13 to 65
Electrical conductivity (EC): 0 to 8
Reaction: strongly alkaline or very strongly alkaline

AC horizons or ACk when present:
Hue: 10YR or 2.5Y
Value: 5 to 7, and 4 to 6 moist
Chroma: 1 or 2
Texture: typically sand including fine sand, loamy sand and loamy fine sand
SAR, ESP, and EC: intermediate in value between the A and C horizon
Reaction: strongly alkaline or very strongly alkaline

C and Cg horizons:
Hue: 10YR, 2.5Y or 5Y
Value: 5 to 8, 4 to 7 moist
Chroma: 1 to 3
Texture: typically sand or fine sand but including loamy fine sand, fine sandy loam, loam, or loamy very fine sand
SAR: 6 to 80
ESP: 6 to 60
EC: 0 to 4
Reaction: moderately alkaline, strongly alkaline or very strongly alkaline

COMPETING SERIES: Lewellen is the only soil in this family.
Lewellen soils formed in loamy and sandy alluvium deposited 51 to 102 centimeters (20 to 40 inches) thick over coarse sand and are on floodplains.

GEOGRAPHIC SETTING:
Parent material: eolian sand,
Landform: swales and hummocks on interdunes
Landscape: sandhills
Flooding: none
Slopes: 0 to 3 percent
Mean annual air temperature: 8 to 10 degrees C. (46 to 50 degrees F.)
Mean annual precipitation: 36 to 46 centimeters (14 to 18 inches)

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Els, Hoffland, Ipage, Marlake, and Valentine soils.
All of these soils do not have ESP greater than 15 or SAR of 13 or more in half or more of the soil volume within 50 centimeters (20 inches) of the mineral soil surface.
Els soils are on similar somewhat poorly drained swales on interdunes.
Hoffland soils are on slightly lower swales on interdunes and are poorly and very poorly drained having a seasonal zone of saturation or aquic conditions beginning at the surface and having ponding on the very poorly drained soil up to 15 centimeters (6 inches).
Ipage soils are on slightly higher swales and hummocks on interdunes and are moderately well drained having a seasonal zone of saturation or aquic conditions beginning at 91 centimeters (36 inches).
Marlake soils are in depressions on interdunes and are very poorly drained having a seasonal zone of saturation or aquic conditions beginning at the surface and having ponding up to 61 centimeters (24 inches).
Valentine soils are on higher dunes and are excessively drained having no seasonal zone of saturation or aquic conditions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage: somewhat poorly drained
Runoff: negligible
Saturated hydraulic conductivity: very high

USE AND VEGETATION: The major uses are livestock grazing and haying. The rangeland native plant community for the saline subirrigated ecological site (R065XY025NE) is principally inland saltgrass alkali sacaton, foxtail barley, and switchgrass.

DISTRIBUTION AND EXTENT: The western sandhills of Nebraska (MLRA 65, LRR G). The series is of moderate extent.

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

SERIES ESTABLISHED: Morrill County, Nebraska, October 1981.

REMARKS: Diagnostic horizons and other features recognized in this pedon:
Ochric epipedon: 0 to 10 centimeters (0 to 4 inches) (the A horizon)
Exchangeable sodium percentage, 15 or more: 0 to 43 centimeters (0 to 17 inches) (the A, AC1, AC2, and C horizons)
Sodium adsorption ratio, 13 or more, in half or more of the soil volume within 51 centimeters (20 inches) of the mineral soil surface: 0 to 43 centimeters (0 to 17 inches) the A, AC1, AC2, and C horizons)
Aquic conditions: 43 to 200 centimeters (17 to 79 inches) (theCg1, Cg2, Cg3 horizons)
2/2006 LRM: Modified format to include metric conversion and change permeability to saturated hydraulic conductivity.
3/2009 RRH: A stream terrace phase or another series or a new series is needed to represent the Wildhorse soils mapped on stream terraces.
3/2009 RRH: Introduction: Revised sentences pertaining to landforms, landscapes, and parent materials. Typical Pedon: Changed to moist colors. Revised horizon nomenclatures. Range of Characteristics: Revised. Geographically Associated Soils: Deleted Elsmere, Lisco, and Selia soils as not near type location and added Marlake soils which are. Revised all definitions. Use and Vegetation: Revised. Diagnostic horizons: revised.
ADDITIONAL DATA: The typical pedon (78NE123002) was analyzed by the National Soil Survey Center Soil Survey Laboratory. Six other pedons from Sheridan County, Nebraska have been analyzed by the SSL.


National Cooperative Soil Survey
U.S.A.