LOCATION UNICORN                 MD+DE

Established Series
SYD-RT/Rev. MDJ
12/2012

UNICORN SERIES

MLRA(s): 153C, 153D
Depth Class: Very deep
Drainage Class (Agricultural): Well drained
Saturated Hydraulic Conductivity Class: Moderately high to high
Permeability Class (obsolete): Moderate in the solum and moderately rapid in the substratum
Landscape: Coastal plain, upland
Landform: flats, coastal plain, knolls, terraces
Parent Material: Loamy eolian deposits over fluviomarine sediments
Slope: 0 to 15 percent
Mean Annual Air Temperature (type location): 13 degrees Centigrade (55 degrees F.)
Mean Annual Precipitation (type location): 1092 millimeters (43 inches)

TAXONOMIC CLASS: Coarse-loamy, mixed, semiactive, mesic Typic Hapludults

TYPICAL PEDON: Unicorn loam, on a one percent slope, in a cultivated field. (Colors are for moist soil.)

Ap--0 to 28 centimeters (0 to 11 inches); brown (10YR 4/3) loam; weak coarse granular structure; very friable, slightly sticky and slightly plastic; common very fine and fine roots throughout; few very fine and fine tubular pores; 2 percent subrounded gravel; neutral; abrupt irregular boundary. (18 to 36 centimeters (7 to 14 inches) thick)

Bt/E--28 to 46 centimeters (11 to 18 inches); dark yellowish brown (10YR 4/6) loam (Bt); yellowish brown (10YR 5/4) loam (E); moderate medium subangular blocky structure; friable, slightly sticky and slightly plastic; common very fine and fine roots throughout; few very fine and fine tubular pores and few medium tubular pores; common faint patchy yellowish brown (10YR 5/4) clay films on faces of peds; 3 percent subrounded mixed gravel; neutral; clear smooth boundary.

Bt1--46 to 61 centimeters (18 to 24) inches; dark yellowish brown (10YR 4/6) loam; moderate medium subangular blocky structure; friable, slightly sticky and slightly plastic; few very fine and fine roots throughout; common very fine and fine tubular pores and few medium tubular pores; common faint dark yellowish brown (10YR 4/6) clay films on faces of peds and in pores; 4 percent subrounded mixed gravel; neutral; abrupt wavy boundary.

2Bt2--61 to 89 centimeters (24 to 35 inches); strong brown (7.5YR 4/6) sandy loam; weak coarse subangular blocky structure; friable, slightly sticky and nonplastic; few fine and medium roots between peds; few very fine and fine tubular pores; common faint brown (7.5YR 4/4) clay films on faces of peds; 6 percent subangular mixed gravel; slightly acid; clear wavy boundary. (Total combined thickness of the argillic horizon ranges from 28 to 100 centimeters (11 to 39 inches)

2C1--89 to 130 centimeters (35 to 51 inches); 70 percent strong brown (7.5YR 5/8) and 30 percent brown (7.5YR 4/4) loamy sand; common yellowish brown (10YR 5/4 and 10YR 5/6), and black (10YR 2/1) lamina; single grain; loose ; strongly acid; abrupt broken boundary.

3C2--130 to 147 centimeters (51 to 58 inches); light yellowish brown (2.5Y 6/3) silt loam; massive; firm, slightly sticky and slightly plastic; common coarse roots throughout and common fine roots in cracks; common very fine and fine tubular pores; common medium faint light brownish gray (2.5Y 6/2) iron depletions; common medium prominent strong brown (7.5YR 4/6) and many coarse distinct brownish yellow (10YR 6/6) iron masses; 5 percent subrounded mixed gravel; very strongly acid; clear wavy boundary.

3C3--147 to 180 centimeters (58 to 71 inches); stratified light yellowish brown (2.5Y 6/3) silt loam and brownish yellow (10YR 6/6) loamy sand; massive; very friable, slightly sticky and nonplastic; common very fine and fine and few coarse roots throughout; common very fine and fine tubular pores; common medium faint light brownish gray (2.5Y 6/2) iron depletions, and common medium and coarse faint olive yellow (2.5Y 6/6) iron masses; extremely acid; abrupt wavy boundary.

4C4--180 to 201 centimeters (71 to 79 inches); 75 percent olive yellow (2.5Y 6/6) and 25 percent brownish yellow (10YR 6/8) loamy sand; single grain; loose; 5 percent subrounded gravel; extremely acid.

TYPE LOCATION: Queen Anne's County, Maryland; approximately 6.9 kilometers East of Sudlersville, in a crop field Southwest of Felton School Road and North of Andover Branch;125 meters from the southwest corner of the field, along the edge of the woods, and 30 feet east of the woods. USGS Sudlersville, Maryland-Delaware topgraphic quadrangle; latitude 39 degrees 12 minutes 2.0 seconds N. and longitude 75 degrees 46 minutes 33.2 seconds W., NAD 1983.

RANGE IN CHARACTERISTICS:
Argillic thickness ranges from 28 to 100 centimeters (11 to 39 inches), average thickness is 55 centimeters (21.8 inches)
Depth to the top of the Argillic Horizon: 15 to 58 centimeters (6 to 23 inches)
Depth to the bottom of the Argillic Horizon: 51 to 140 (20 to 55 inches)
Solum Thickness (including the BC horizon (if it occurs)): 38 to 152 centimeters (15 to 60 inches):

Rock Fragment content: 0 to 5 percent in the surface and upper B horizon, and 0 to 25 percent in the lower B and C horizons, dominantly quartzite and chert gravel.
Content of Silt: 35 to 60 percent in the A, E, and upper Bt
Soil reaction: Extremely acid to strongly acid, except where limed

Range of Individual Horizons:
Ap or A horizon (if it occurs):
Color--hue of 10YR, value of 3 to 5, and chroma of 2 to 6
Texture (fine-earth fraction) -- loam or silt loam, and less commonly fine sandy loam and sandy loam
E or BE horizon (if they occur):
Color--hue of 10YR, value of 4 to 6, and chroma of 3 to 8
Texture (fine-earth fraction) -- loam or silt loam, and less commonly fine sandy loam and sandy loam
Other features--0 to 5 percent gravel

Bt horizon:
Color--hue of 7.5YR to 2.5Y, value of 4 to 6, and chroma of 3 to 8
Texture (fine-earth fraction) -- loam or silt loam
Redoximorphic features (if they occur below a depth of 102 centimeters)--iron masses in shade of red, yellow,
or brown and iron depletions in shades of brown, yellow, olive, or gray
Other features--0 to 5 percent gravel

2Bt horizon:
Color--hue of 7.5YR to 2.5Y, value of 4 to 6, and chroma of 3 to 8
Texture (fine-earth fraction)-- sandy loam or loam, with lower silt content than overlying horizons, and may include thin layers of clay loam, sandy clay loam, or loamy sand
Redoximorphic features (if they occur below a depth of 102 centimeters)--iron masses in shade of red, yellow, or brown and iron depletions in shades of brown, yellow, olive, or gray
Other features--0 to 10 percent gravel

BC horizon (if it occurs):
Color--hue of 7.5YR or 10YR, value of 4 to 7, and chroma of 3 to 8
Texture (fine-earth fraction)-loamy sand or sandy loam and their gravely analogs
Redoximorphic features (if they occur)--iron masses in shade of red, yellow, or brown and iron depletions in shades of brown, yellow, olive, or gray
Other features--0 to 25 percent gravel

C horizon:
Color--hue of 7.5YR to 2.5Y, value of 4 to 8, and chroma of 1 to 8
Texture (fine-earth fraction)-- commonly stratified, with textures of loamy sand, sandy loam, silt loam, and loam, and less commonly sandy clay loam or clay loam, and their gravelly analogues
Redoximorphic features (if they occur)--iron masses in shade of red, yellow, or brown and iron depletions in shades of brown, yellow, olive, or gray
Other features--0 to 25 percent gravel

COMPETING SERIES:
Adyeville soils formed in residuum from interbedded sandstone, siltstone, and shale, are moderately deep, and are somewhat excessively drained soils on hills
Greenwich soils do not have a water table within 183 centimeters (72 inches) from the surface
Grosstown soils formed in gravelly fluviomarine sediments, and do not have a water table within 183 centimeters (72 inches) from the surface
Philomont soil formed in residuum weathered from gneissic and granitic rocks that have been intruded and sheared with basic greenstones
Swedesboro soils formed in loamy and sandy near shore marine sediments that contain glauconite

GEOGRAPHIC SETTING:
Landscape: Coastal Plain, uplands
Landform: flats, coastal plain, knolls, terraces
Parent Material: Loamy eolian deposits over fluviomarine sediments
Elevation: 0.3 to 37 meters (1 to 120 feet)
Frost-free period: 180 to 120 days
Slope: 0 to 15 percent
Elevation: 0.3 to 37 meters (1 to 120 feet)
Frost-free period: 180 to 220 days
Mean Annual Air Temperature (type location): 13.9 degrees Centigrade (56 degrees F.)
Mean Annual Precipitation (type location): 1143 millimeters (45 inches)

GEOGRAPHICALLY ASSOCIATED SOILS:
Carmichael soils -- on lower landforms, and are poorly drained
Downer soils -- on slightly higher landforms and do not have a fluctuating seasonal water table above 183 centimeters (72 inches)
Fallsington soils -- on lower landforms, are poorly drained, and have a fine-loamy particle-size control section
Hammonton soils -- on slightly lower landforms, are moderately well drained
Ingleside soils -- on similar landforms, do not have loam and silt loam textures in the solum
Pineyneck soils -- on slightly lower landforms, are moderately well drained
Pone soils --on lower landforms, are very poorly drained
Sassafras soils -- On slightly higher landforms do not have a fluctuating seasonal water table above 183 centimeters (72 inches), and have a fine-loamy particle-size control section

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage Class (Agricultural): Well Unicorn soils are well drained, but have a seasonally high water table from 102 to 183 centimeters (40 to 72 inches) from January to May
Internal Free Water Occurrence: Deep, common
Index Surface Runoff: Low
Saturated Hydraulic Conductivity Class: Moderately high to high
Permeability Class (obsolete): Moderate in the solum and moderately rapid in the substratum
Flooding Frequency and Duration: None
Ponding Frequency and Duration: None

USE AND VEGETATION:
Major Uses: Most areas of Unicorn soils are cleared and used for growing corn, soybeans, wheat, and barley. Some areas are irrigated.
Dominant Vegetation: Where wooded--areas of second growth forest contain white oak (Quercus alba), black gum (Nyssa sylvatica), pignut hickory (Carya glabra), American beech (Fagus grandifolia), red maple (Acer rubrum), black oak (Quercus velutina), Virginia pine (Pinus virginiana), tulip poplar (Liriodendron tulipifera), and sweetgum (Liquidambar styraciflua) in the canopy; and lowbush blueberry (Vaccinium angustifolium), huckleberry (Gaylussacia), sassafras (Sassafras albidum), dogwood (Cornus florida), black cherry (Prunus serotina), American holly (Ilex opaca), cedar (Juniperus virginiana), oblong-leaf serviceberry (Amelancheir canadensis), and deerberry (Vaccinium stamineum) in the understory.

DISTRIBUTION AND EXTENT:
Distribution: Coastal Plain of Maryland and Delaware
Extent: Moderately extensive

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia

SERIES ESTABLISHED: Queen Anne's County, Maryland, 1995.

REMARKS:
This soil was formerly included in the Sassafras series. It is distinguished from Sassafras by having a particle size control section that is coarse-loamy rather than fine-loamy, and a seasonal high water table between 102 and 183 centimeters (40 and 72 inches) which will affect its use.

Diagnostic horizons and soil characteristics recognized in this pedon are:
Ochric epipedon--the zone from 0 to 28 centimeters (0 to 11 inches) (Ap horizon)
Argillic horizon--the zone from 46 to 89 centimeters (18 to 35 inches) (Bt1 and 2Bt2 horizons)
Aquic conditions--the zone from 130 to 201centimeters
Series control section--the zone from 0 to 152 centimeters (0 to 60 inches)

ADDITIONAL DATA
Typical Data Map unit: 586172
Typical User Pedon ID: 07MD035002_Unicorn
Previous Revision: 11/2002, DAS-SLD

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National Cooperative Soil Survey
U.S.A.