LOCATION LETA MOEstablished Series
TAXONOMIC CLASS: Clayey over loamy, smectitic, mesic Fluvaquentic Hapludolls
TYPICAL PEDON: Leta silty clay - on a level area in a cultivated field. at an elevation of 685 feet. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 8 inches; very dark gray (10YR 3/1) silty clay, gray (10YR 5/1) dry; weak fine granular structure; very firm, many fine roots; strong effervescence; slightly alkaline; abrupt smooth boundary.
A--8 to 13 inches; very dark grayish brown (2.5Y 3/2) silty clay loam, grayish brown (2.5Y 5/2) dry; moderate medium subangular blocky structure; very firm, common fine roots; strong effervescence; slightly alkaline; clear smooth boundary. (Combined thickness of the A horizon is 10 to 24 inches thick.)
Bg--13 to 25 inches; dark grayish brown (2.5Y 4/2) silty clay; moderate medium subangular blocky structure; very firm, few fine roots; few fine prominent dark yellowish brown (10YR 4/4) masses of iron accumulation throughout; strong effervescence; slightly alkaline; clear smooth boundary. (0 to 15 inches thick)
2Cg--25 to 60 inches; stratified grayish brown (10YR 5/2) very fine sandy loam and silt loam; massive with bedding planes along horizontal surfaces of strata; common fine distinct dark yellowish brown (10YR 4/4) masses of iron accumulation throughout; strong effervescence; slightly alkaline.
TYPE LOCATION: Lafayette County, Missouri; about 2 miles west of Lexington (north of Missouri River); approximately 5,000 feet west and 1,000 feet north of the southeast corner of sec. 31, T. 51 N., R. 27 W; Lexington West USGS quadrangle.
RANGE IN CHARACTERISTICS: Depth to the loamy material ranges from 20 to 38 inches. The mollic epipedon ranges from 10 to 24 inches thick. The series control section commonly is slightly alkaline or moderately alkaline throughtout, but some pedons are neutral in the upper 10 inches.
The A horizon has hue of 10YR or 2.5Y, value of 2 or 3 and chroma of 1 or 2. It is silt loam, silty clay loam, or silty clay.
The Bg horizon has hue of 10YR or 2.5Y, value of 3 to 5 and chroma of 1 to 3 with distinct or prominent masses of higher chroma. If value of 3 occurs below 24 inches, it is separated from the mollic epipedon by strata of higher value. Texture is silt loam, silty clay loam, silty clay or clay and averages between 35 and 48 percent clay.
The 2Cg horizon has hue of 10YR to 5Y, value of 4 to 6 and chroma of 1 or 2 with masses of higher chroma. It commonly is stratified silt loam and very fine sandy loam, but pedons with sandy loam strata are not excluded. Some pedons have a sandy substratum below the loamy layers.
COMPETING SERIES: This is the Parkville series in the same family. Similar soils include the Blencoe, Myrick and Onawa series. Parkville soils have clayey textures to depths of less than 20 inches.
Blencoe soils are not calcareous in the upper part of the particle size control section. Myrick soils have clayey textures to a depth less than 20 inches and are wetter. Onawa soils have a thinner dark colored surface layer.
GEOGRAPHIC SETTING: Leta soils are on nearly level recent flood plains along major streams. The slope gradient is 0 to 2 percent. They formed in 20 to 38 inches of moderately fine and fine textured alluvium deposited over coarser textured alluvial materials. The mean annual temperature ranges from 53 degrees to 57 degrees F, and mean annual precipitation ranges from 35 to 42 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Haynie, Kenmoor, Modale, Myrick, Sarpy, Waldron, and Waubonsie series. The Haynie, Kenmoor, Modale, Sarpy, and Waubonsie soils have less clay in the solum and are on adjacent landscapes. Myrick soils have clayey textures to depth of less than 20 inches and are in depressions on adjacent landscapes. Waldron soils are clayey throughout and occur on adjacent landscapes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained. Runoff is low. Permeability is slow in the upper part and moderate or rapid in the lower part. An apparent water table has an upper limit of 1.0 to 3.0 feet during November to June. These soils are subject to rare or frequent flooding.
USE AND VEGETATION: Soils are cropped to corn, soybeans, and wheat. Native vegetation is mostly willow and cottonwood.
DISTRIBUTION AND EXTENT: Along the Missouri River and its tributaries (MLRAs 107 and 115) in Missouri. These soils are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Lafayette County, Missouri, 1970.
REMARKS: Diagnostic horizons and features recognized in this series are: mollic epipedon - the zone from the surface of the soil to a depth of 13 inches (Ap and A horizons); cambic horizon - the zone from approximately 13 inches to 25 inches (Bg horizon); udic moisture regime.
Leta soils are prime farmland where not frequently flooded.