LOCATION LEX NE+SDEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, calcareous, mesic Fluvaquentic Endoaquolls
TYPICAL PEDON: Lex silt loam with a slope of less than 1 percent in irrigated cropland. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 7 inches; gray (10YR 5/1) silt loam, very dark gray (10YR 3/1) moist; weak medium granular structure; hard, friable; many, medium roots; violent effervescence; slightly alkaline; clear smooth boundary.
A1--7 to 9 inches; gray (10YR 5/1) silt loam, very dark gray (10YR 3/1) moist; moderate medium granular structure; hard, friable; common fine roots; violent effervescence; slightly alkaline; clear smooth boundary.
A2--9 to 18 inches; gray (N 5/0) silty clay loam, very dark gray (N 3/0) moist; moderate fine and medium subangular blocky structure; hard, firm; common fine roots, few fine tubular pores; strong effervescence; slightly alkaline; gradual smooth boundary. (Combined thickness of A is 7 to 20 inches thick.)
C--18 to 23 inches; light gray (2.5Y 7/2) fine sandy loam, grayish brown (2.5Y 5/2) moist; few small and medium prominent dark yellowish brown (10YR 4/4) iron masses in the soil matrix; massive; slightly hard, friable, few fine roots, few fine tubular pores; slight effervescence; slightly alkaline; abrupt smooth boundary. (5 to 18 inches thick)
2Cg--23 to 80 inches; light gray (10YR 7/2) gravelly sand; light brownish gray (10YR 6/2) moist; few large prominent reddish brown (5YR 5/4) iron masses in the soil matrix; single grain; loose; slightly alkaline.
TYPE LOCATION: Buffalo County, Nebraska, 4 miles east of Kearney, Nebraska; 150 feet east and 2,000 feet south of the northwest corner, sec. 1, T. 8 N., R. 15 W. Newark topographic quadrangle; latitude 40 degrees, 41 minutes, 37 seconds North and longtitude 98 degrees, 58 minutes, 9 seconds West.
RANGE IN CHARACTERISTICS:
Soil moisture: Soil is moist in the in the control section from December through April and intermittently moist from May through December. The driest months are July through September
Depth to secondary carbonates: Calcium carbonate is typically at the surface or within a depth of 10 inches
Depth to redoximorphic features: Few to common, fine and medium, faint, distinct or prominent iron concentrations, with hue of 5YR, 7.5YR or 10YR, value of 3 to 6 moist and chroma of 2 to 8 are common; these redoximorphic features are found in the lower part of the A horizon and throughout the C horizon.
Depth to endosaturation: 1 to 3 feet
Thickness of the mollic epipedon: 10 to 24 inches
Depth to rock fragments: Depth to the coarse sand or gravelly sand is typically 23 to 35 inches, but ranges from 20 to 40 inches
A horizon: (AC horizon if present)
Hue: 10YR or 2.5Y
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 0 to 2
Texture: silt loam or loam and less commonly clay loam or silty clay loam.
E.C. (mmhos.cm): 0-4
Reaction: slightly alkaline or moderately alkaline
C horizon:
Hue: 10YR or 2.5Y
Value: 5 to 7 dry, 4 to 6 moist
Chroma: 1 or 3
Texture: loam, silt loam, sandy clay loam, clay loam or very fine sandy loam, fine sandy loam and sandy loam with more than 18 percent clay. This horizon is commonly stratified with varying colors and textures of soil material
E.C. (mmhos.cm): 0-4
Reaction: slightly acid to moderately alkaline
2C horizon:
Hue: 10YR or 2.5Y
Value: 6 to 8 dry, 5 to 7 moist
Chroma: 1 to 4
Texture: gravelly sand or gravelly coarse sand but ranges to include sand and coarse sand
Rock Fragments: Percent gravel by volume is typically 15 to 35 percent but ranges from 5 to 35 percent
Reaction: slightly acid to slightly alkaline
COMPETING SERIES: These are the Loveland, Swope and Woofus series in the same family and the Gibbon, Lamo, Leshara and Alda series in closely related families. Loveland soils have a higher seasonal water table during the growing season. Swope and Woofus soils are dry for longer periods in the soil moisture control section. Woofus soils have a higher seasonl high water table and are at elevations above 5,000 feet. Gibbon, Lamo and Leshara soils are fine-silty and do not have gravelly sand and coarse sand above a depth of 40 inches. Alda soils are coarse-loamy.
GEOGRAPHIC SETTING: Lex soils are nearly level and formed in recent loamy alluvium on flood plains of larger streams. The slope gradient ranges from 0 to 2 percent. Range of mean annual precipitation is 18 to 30 inches and the range of mean annual temperature is 46 to 53 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alda, Gibbon, Gothenburg, Platte, and Wann soils. Gothenburg soils are less than 10 inches thick over the gravelly sand. Platte soils are at slightly lower elevations and have gravelly sand between depths of 10 and 20 inches. Wann soils are coarse-loamy. Wann and Alda soils are on similar landscapes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Runoff is low. Permeability is moderate or moderately slow in the solum and very rapid in the substratum. The seasonal high water table ranges from 1 to 3 feet. It is highest during winter and early spring when stream flow is highest. During midsummer it commonly recedes to 3 to 6 feet. Flooding is rare or occasional.
USE AND VEGETATION: This soil is used principally as irrigated cropland; however, a small acreage is also used for dryland crops, range, and hayland. Corn, alfalfa, and soybeans are the most common grown crops. The native vegetation is mainly big bluestem, switchgrass, indiangrass, and little bluestem.
DISTRIBUTION AND EXTENT: The Lex series is in central and eastern Nebraska and is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Buffalo County, Nebraska, 1967.
REMARKS: This soil was formerly correlated as a moderately deep phase of Lamoure soils. A saline-alkali phase is recognized. These soils generally are not saturated at depths between 40 and 50 cm during the growing season. The diagnostic horizons and other features recognized in this pedon are: mollic epipedon--the zone from 0 to 18 inches (Ap, A1 and A2 horizon); an irregular decrease in organic carbon content from a depth of 25 cm to a depth of 125 cm; and aquic soil conditions--the zone from 23 to 80 inches (2Cg horizon).
OSD Modification RRZ 7/2002: OSD needs to allow chromas of less than 2 in the C and Cg horizons. Chromas of 3 and 4 in these horizons may fail the Endoaqualls classification of low cxhroma depletions are not present. Depletions are indicated in the typically profile at this time. Superactive added to taxonomy