LOCATION NAVAN WIEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argiaquolls
TYPICAL PEDON: Navan silt loam - on a slope of less than 1 percent in a cultivated field at an elevation of about 810 feet above mean sea level. (Colors are for moist soil unless otherwise stated.)
Ap--0 to 10 inches; black (N 2.5/0) silt loam, dark gray (N 4/0) dry; weak fine subangular blocky structure; very friable; high organic matter content; slightly alkaline; abrupt smooth boundary.
A--10 to 12 inches; black (10YR 2/1) clay loam, dark grayish brown (10YR 4/2) dry; weak fine subangular blocky structure; firm; few fine distinct dark grayish brown (2.5Y 4/2) masses of iron accumulation; slightly alkaline; abrupt smooth boundary. (Combined thickness of the Ap and A horizons ranges from 10 to 20 inches.)
Btg1--12 to 17 inches; dark grayish brown (2.5Y 4/2) clay loam; moderate fine and very fine subangular blocky structure; firm; thin clay films on faces of some peds and in pores and channels; distinct black (10YR 2/1) soil material from the horizon above, filling some channels; many fine distinct light olive brown (2.5Y 5/4) masses of iron accumulation; common medium distinct dark gray (10YR 4/1) iron depletions; slightly alkaline; clear wavy boundary.
Btg2--17 to 29 inches; olive gray (5Y 5/2) clay loam; moderate fine subangular blocky structure; firm; thin clay films on faces of some peds and in pores and channels; common fine and medium prominent yellowish brown (10YR 5/6) masses of iron accumulation; slightly alkaline; clear smooth boundary. (Combined thickness of the Btg horizons ranges from 8 to 26 inches.)
2BCg--29 to 37 inches;light olive gray (5Y 6/2) silty clay loam; moderate medium and fine prismatic structure; firm; many medium prominent yellowish brown (10YR 5/6) masses of iron accumulation; strongly effervescent; moderately alkaline. (0 to 10 inches thick.)
2Cg--37 to 60 inches; mixed gray (5Y 5/1), yellowish brown (10YR 5/6), and greenish gray (5GY 6/1) silty clay loam with thin strata of silt loam and silty clay; massive; firm; tends to break to weak thick plates along depositional cleavage planes; strongly effervescent; moderately alkaline.
TYPE LOCATION: Rock County, Wisconsin, 1150 feet south and 130 feet east of the northwest corner of sec. 6, T. 2 N., R. 10 E. USGS Orfordville, Wisconsin Topographic quadrangle; lat. 42 degrees 40 minutes 08 seconds N., and long. 89 degrees 22 minutes 01 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: Thickness of the loamy outwash mantle and depth to the stratified lacustrine deposits ranges from 18 to 36 inches. Thickness of the mollic epipedon ranges from 10 to 20 inches. Depth to the base of soil development ranges from 20 to 42 inches. Depth to carbonates ranges from 20 to 40 inches. The particle-size control section averages from 24 to 35 percent clay and from 16 to 50 percent fine sand or coarser. Volume of rock fragments ranges from 0 to 20 percent in the loamy outwash mantle. Reaction ranges from slightly acid to slightly alkaline in the upper part of the soil and is slightly alkaline or moderately alkaline in the lower part. Distinct or prominent redox accumulations are in the lower part of the mollic epipedon in many pedons and are throughout the soil below the mollic epipedon. Dominant chroma of 2 or less (or 1 or less depending on hue) is directly below the mollic epipedon. Saturation occurs at 0 to 1 foot for long periods in most years.
The Ap or A horizon has hue of 10YR or is neutral in hue, value of 2 or 3, and chroma of 0 to 2. Texture of the surface layer is silt loam or loam. Texture of the A horizon below the surface layer is silt loam, loam or clay loam.
The Btg horizon has hue of 10YR, 2.5Y or 5Y; value of 4 to 6; and chroma of 1 or 2. Texture is loam, clay loam, or sandy clay loam.
The 2BCg horizon typically has hue of 7.5YR, 10YR, 2.5Y or 5Y but hue ranges to 5G in some pedons. Value is 4 to 6 and chroma is 1 to 6. Texture is typically silty clay loam, but some pedons have thin strata of finer or coarser textures;
The 2C horizon typically has hue of 7.5YR, 10YR, 2.5Y, or 5Y but hue ranges to 5G in some pedons. Value is 4 to 6 and chroma is 0 to 6. Texture is mostly silty clay loam with thin strata of finer or coarser textures. Clay content averages more than 25 percent and total sand content ranges from 15 to 40 percent.
COMPETING SERIES: These are the Barry, Brookston, Buntingville, Clackamas, Cordova, Hamel, Jameston, Millgrove, Navunon, Nosoni, Radioville, Rensselaer, Tallmadge, and Westland series. Barry, Brookston, Clackamas, Cordova, Jameston, and Navunon soils do not have fine stratification in the lower part of the series control section and have coarse fragments there. In addition, Brookston soils are more than 40 inches deep to carbonates; Clackamas soils do not have carbonates within the series control section; and Navunon soils typically have a lithic contact within 60 inches. Buntingville, Hamel, and Nosoni soils have mollic epipedons more than 24 inches thick. Millgrove and Rensselaer soils have less than 20 percent clay in the lower part of the series control section. Radioville soils are more than 40 inches deep to stratified lacustrine deposits. Tallmadge soils have a lithic contact at 40 to 60 inches. Westland soils have 85 to 90 percent sand in the lower part of the series control section.
GEOGRAPHIC SETTING: The Navan soils are on glacial lake basins and low stream benches. Slope ranges from 0 to 3 percent. These soils formed in a mantle of loamy outwash and in the underlying mostly clayey and silty stratified lacustrine deposits. Mean annual precipitation ranges from 26 to 35 inches. Mean annual air temperature ranges from 46 to 53 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aztalan, Colwood, Hebron, Mosel, and Poy soils. The moderately well drained Hebron and the somewhat poorly drained Aztalan and Mosel soils form a drainage sequence with the Navan soils. These soils are adjacent to and higher lying than the Navan soils. Aztalan soils have mollic epipedons and Mosel soils do not have mollic epipedons. Colwood soils formed in stratified silt and sand while Poy soils have finer textured horizons in the upper part of the solum. Poy and Colwood soils occupy a similar setting as the Navan soils.
DRAINAGE AND PERMEABILITY: Poorly drained. The potential for surface runoff is low. Permeability is moderate in the loamy outwash mantle and moderately slow in the lacustrine deposits. In some places these soils are subject to common flooding. These soil have an apparent seasonal high water table at a depth of 0 to 1 foot for long periods in most years.
USE AND VEGETATION: Most areas are drained and are used for cropland. Common crops are corn, oats and hay. Other areas have been retained primarily in pasture. Native vegetation is marsh grasses and a few trees.
DISTRIBUTION AND EXTENT: Eastern Wisconsin. The Navan soils are of moderate extent.
MLRA OFFICE RESPONSIBLE: Indianapolis, Indiana
SERIES ESTABLISHED: Green County, Wisconsin, 1969.
REMARKS:
7/04 This revision redefines the series concept to include only those soils formed in a loamy outwash mantle and the underlying stratified silty and clayey lacustrine deposits. A new typical pedon is used to better reflect this concept. Soils correlated as Navan that formed in loamy outwash and underlying clayey glacial till are excluded. This includes at least some of the acres in the Kenosha-Racine, Ozaukee, and Winnebago soil surveys and possibly some areas in other surveys. These areas should be correlated to another (new?) series when the surveys are updated.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - 0 to 12 inches (Ap, A); argillic horizon - 12 to 29 inches (Btg1, Btg2) aquic feature - saturaton and redox accumulations in the lower part of the mollic epipedon.