LOCATION MANSFIELD RI+VTEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, active, nonacid, mesic Typic Humaquepts
TYPICAL PEDON: Mansfield silt loam in an unimproved pasture at an elevation of about 90 feet. (Colors are for moist soil unless otherwise noted.)
Oa--0 to 4 inches; black (10YR 2/1) muck. (0 to 5 inches thick)
A--4 to 12 inches; very dark gray (10YR 3/1) silt loam; dark gray (10YR 4/1) dry; moderate, medium granular structure; very friable; many fine roots; few scattered pebbles; moderately acid; abrupt wavy boundary. (5 to 12 inches thick)
Bg1--12 to 18 inches; gray (5Y 5/1) silt loam; weak medium subangular blocky structure; friable; many fine roots; 5 percent gravel; common medium prominent yellowish brown (10YR 5/8) redoximorphic concentrations; slightly acid; clear wavy boundary.
Bg2--18 to 23 inches; gray (5Y 5/1) silt loam; weak thick plates parting to weak medium subangular blocky structure; firm; few fine roots; 10 percent gravel; many medium prominent yellowish brown (10YR 5/8) redoximorphic concentrations; neutral; clear wavy boundary. (Combined thickness of the Bg horizons is 8 to 30 inches)
Cd--23 to 60 inches; dark gray (5Y 4/1) gravelly fine sandy loam; weak thick platy structure; extremely firm, brittle; 20 percent gravel; many medium prominent yellowish brown (10YR 5/8) redoximorphic concentrations; neutral.
TYPE LOCATION: Newport County, Rhode Island; town of Little Compton, 1320 feet east on Simmons Road from the junction of Simmons Road and Willow Avenue, 550 south of Simmons Road. USGS Westport quadrangle; 41 degrees 30 minutes 34 seconds N. and 71 degrees 9 minutes 59 seconds W., NAD 27.
RANGE IN CHARACTERISTICS: Thickness of the solum commonly is 20 to 36 inches but the range includes from 14 to 36 inches in some places. It corresponds closely to the depth to the dense substratum. Depth to bedrock is commonly more than 6 feet. Rock fragments range from 0 to 25 percent in the solum and from 10 to 35 percent in the substratum. Except where the surface layer is stony, the fragments are mostly subrounded gravel or channers. Unless limed, the soil is very strongly acid to slightly acid in the A horizon and strongly acid to neutral below. At least one subhorizon within a depth of 40 inches is moderately acid, slightly acid or neutral.
Where present, the O horizon has hue of 5YR through 10YR, value of 2 or 3 and chroma of 1 or 2. It is dominantly highly or moderately decomposed plant material derived from sapric or hemic materials.
The A horizon is neutral or has hue of 7.5YR through 2.5Y, value of 2 or 3 and chroma of 0 through 2. It is silt loam, loam or very fine sandy loam in the fine earth and includes mucky analogs. Where the A horizon is thin, mixing of the upper profile layers results in an umbric epipedon. Structure is weak or moderate granular. Consistence is friable or very friable and nonsticky or slightly sticky.
The Bg horizon is neutral or has hue of 10YR through 5Y, value of 3 through 6, and chroma of 0 through 2. It has faint to prominent redoximorphic features. Fine earth texture is silt loam, very fine sandy loam or loam with more than 40 percent silt. The horizon is massive or has weak or moderate granular, weak or moderate subangular blocky or weak platy structure. Consistence is friable or firm and nonsticky or slightly sticky.
The Cd horizon is neutral or has hue of 2.5Y or 5Y, value of 3 through 6 and chroma of 0 through 4. It is typically mottled due to wetness. Chroma of 3 and 4 are limited to subhorizons below a depth of 30 inches. Texture is silt loam, loam, very fine sandy loam or fine sandy loam in the fine earth. The structure is geogenically derived, appearing in the form of weak or moderate, medium to very thick, thin plates or it is massive. Consistence is firm to extremely firm.
COMPETING SERIES: There are no series currently in the same family.
The Whitman series is in a closely related family. Whitman soils have a B horizon with less than 40 percent silt and are dominated by rock fragments of granite, gneiss or schist.
GEOGRAPHIC SETTING: Mansfield soils are nearly level soils in depressions, drainageways and lowlying areas of glaciated uplands. Slope ranges from 0 to 3 percent. The soils formed in glacial till derived primarily from dark gray phyllite, slate, shale, schist and conglomerate. Mean annual temperature is 45 to 54 degrees F., mean annual precipitation is 40 to 50 inches; and the growing season is 120 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bernardston, Broadbrook, Dutchess, Hinckley, Merrimac, Narragansett, Nassau, Newport, Pittstown, Quonset, Rainbow, Stissing, Wapping and Warwick soils. The well drained Bernardston and Newport, moderately well drained Pittstown and poorly drained Stissing soils are associated in a drainage sequence. Broadbrook, Dutchess and Narragansett soils are well drained. Nassau soils are shallow to bedrock. The excessively drained Hinckley and Quonset and somewhat excessively drained Merrimac and Warwick soils are on nearby outwash plains and terraces. Rainbow and Wapping soils are moderately well drained.
DRAINAGE AND PERMEABILITY: Very poorly drained. Surface runoff is negligible to high and the soils are often ponded in depressions. Permeability is moderate in the solum and slow or very slow in the substratum. Saturated hydraulic conductivity is moderately high in the solum and low or moderately low in the substratum. These soils have a water table near or above the surface most of the year.
USE AND VEGETATION: Mostly wooded or idle. A few areas are in pasture. Common trees are gray birch, red maple, hemlock, elm and spruce. Other plants include alder, sedges, rushes and cattails.
DISTRIBUTION AND EXTENT: Southeastern Rhode Island and Vermont. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Amherst, Massachusetts
SERIES ESTABLISHED: Bristol County, Massachusetts, 1920.
REMARKS: Mansfield soils were previously classified as Humic Fragiaquepts. This revision (2003) adds cation exchange activity class to the taxonomic classification. Type Location revised due to possible typographic error (this is noted in the Accompanying Information file stored at the responsible MLRA Office. Geographic coordinates determined in 2003 from the revised narrative description of the type location.