LOCATION UNICORN MDEstablished Series
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 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. (7 to 14 inches thick)
Bt/E--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. (0 to 7 inches thick)
Bt1--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. (5 to 12 inches thick)
2Bt2--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. (0 to 15 inches thick)
2C1--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 5/6), and black (10YR 2/1) lamina; single grain; very friable; strongly acid; abrupt broken boundary.
3C2--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) masses of iron accumulation; 5 percent subrounded mixed gravel; very strongly acid; clear wavy boundary.
3C3--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 distinct olive yellow (2.5Y 6/6) masses of iron accumulation; extremely acid; abrupt wavy boundary.
4C4--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; east of Sudlersville, located 3300 feet SW of the intersection of Felton School Road and Andover Branch, and 4,090 feet ENE of the intersection of Rte. 300 and Peter's Corner Road; approximately 30 feet east of the woods and 410 feet from the southwest corner of the field. USGS Sudlersville Maryland - Delaware topographic quadrangle; lat. 39 degrees 12 minutes 1.4 seconds N. and long. 75 degrees 46 minutes 35.1 seconds W., NAD 83.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 22 to 55 inches. Rock fragments of dominantly quartzite and chert gravel range from 0 to 5 percent in the surface and upper B horizon, and 0 to 25 percent in the lower B and C horizons. Silt content in the A, E, and upper Bt ranges from 35 to 60 percent. The soil ranges from extremely acid through strongly acid in unlimed areas through neutral in heavily limed areas.
The Ap or A horizon has hue of 10YR, value of 3 through 5, and chroma of 2 through 6. It is predominantly loam or silt loam, and less commonly fine sandy loam and sandy loam. It has 0 to 5 percent gravel.
The E horizon is usually present only in pedons that have not been disturbed. Its colors are similar to the BE horizon. It is loam or, less commonly fine sandy loam.
The BE horizon, where present, has hue of 10YR, value of 4 to 6, and chroma of 3 to 8. It is loam or silt loam or, less commonly sandy loam. It has 0 to 5 percent gravel.
The Bt horizon has hue of 7.5YR through 2.5Y, value of 4 to 6, and chroma of 3 to 8. It is loam or silt loam. Masses of iron accumulation have hue of 5YR through 10YR, value of 4 to 6, and chroma of 4 to 8. Iron depletions, when present, are below a depth of 40 inches from the surface, have hue of 10YR, value of 6, and chroma of 2.
The 2Bt horizon, where present, has the same colors as the Bt. It has textures of 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. It has 0 to 10 percent gravel.
The BC horizon, where present, has hue of 10YR or 7.5YR, value of 4 to 7 and chroma of 3 to 8. It is usually sandy loam or loamy sand and their gravelly analogues, or occasionally loam through fine sandy loam. Masses of iron accumulation have hue of 5YR through 10YR, value of 4 to 6, and chroma of 4 to 8. Iron depletions, when present, have hue of 10YR, value of 6 or 7, and chroma of 2. It has 0 to 25 percent gravel.
The C horizons have hues of 7.5YR through 2.5Y, values of 4 to 8, and chroma of 1 to 8. They are 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. Masses of iron accumulation and zones of iron depletion have hues of 7.5YR through 5Y, values of 4 to 7, and chroma of 1 to 8. They have 0 to 25 percent gravel.
COMPETING SERIES: These are the Brentsville, Dunellen, Germano, Greenwich, Lansdale, Rigley, and Swedesboro soils. Brentsville, Germano, and Lansdale soils formed in residuum and are less than 60 inches to bedrock. Dunellen has hues redder than 7.5YR in the B horizon, and up to 50 % rock fragments of siltstone, shale, and sandstone. Rigley soils formed in colluvium, and Swedesboro soils have glauconite in the substratum. Greenwich soils do not have a water table within 72 inches from the surface.
GEOGRAPHIC SETTING: Unicorn soils are on level to strongly sloping uplands of the mid-Atlantic Coastal Plain. Slopes range from 0 to 30 percent. The soils formed in loamy sediments high in silt overlying stratified fluvial Coastal Plain sediments. Mean annual temperature is 55 degrees F., and mean annual precipitation is 43 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Carmichael, Downer, Fallsington, Hammonton, Ingleside, Pineyneck, Pone, and Sassafras soils. Ingleside soils do not have loam and silt loam textures in the solum. Sassafras and Downer soils do not have a fluctuating seasonal water table above 72 inches. Pineyneck and Hammonton soils are moderately well drained. Carmichael and Fallsington soils are poorly drained. Pone soils are very poorly drained.
DRAINAGE AND PERMEABILITY: Unicorn soils are well drained, but have a seasonally high water table from 42 to 72 inches from January to May. Runoff is slow; permeability is moderate in the solum and moderately rapid to slow in the substratum.
USE AND VEGETATION: Most areas of Unicorn soils are cleared and used for growing corn, soybeans, wheat, and barley. Some areas are irrigated. 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: Coastal Plain of Maryland. The series is moderately extensive.
MLRA OFFICE 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 42 and 72 inches which will affect its use.
Diagnostic horizons and features recognized in this pedon are an ochric epipedon; an argillic horizon; and masses of iron accumulation or zones of iron depletion, between 42 and 72 inches, but not within the upper 24 inches of the argillic horizon.
ADDITIONAL DATA: None
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation MD0179 UNICORN 0- 30 52- 58 190-210 42- 48 5- 120SOI-5 FloodL FloodH Watertable Kind Months Bedrock Hardness MD0179 NONE 4.0-6.0 APPARENT JAN-MAY 99-99
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC- MD0179 0-11 SIL L 0- 0 90-100 7-15 5- 15 MD0179 11-24 SIL L 0- 0 90-100 8-18 1- 9 MD0179 24-35 SL L 0- 0 85-100 5-15 1- 5 MD0179 35-54 LS S GR-SL 0- 0 65-100 3- 8 1- 3 MD0179 54-72 SR GR-LS SIL 0- 0 65-100 5-27 1- 9
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll MD0179 0-11 3.5- 5.0 .5-3. 0- 0 0.6- 6.0 LOW MD0179 11-24 3.5- 5.5 0.-.5 0- 0 0.6- 2.0 LOW MD0179 24-35 3.5- 5.5 0.-.5 0- 0 0.6- 6.0 LOW MD0179 35-54 3.5- 5.5 0.-.5 0- 0 2.0- 20 LOW MD0179 54-72 3.5- 5.5 0.-.5 0- 0 0.6- 6.0 LOW