LOCATION COARDS MD+DE NJ
Established Series
DMB-PK/Rev. DCS/RBT
05/2023
COARDS SERIES
MLRA(s): 153D
Soil Survey Regional Office (SSRO) Responsible: Raleigh, North Carolina
Depth Class: Very deep
Drainage Class: Subaqueous (permanently submersed)
Saturated Hydraulic Conductivity: Low to moderately low
Parent Material: Fine mainland cove, lagoon bottom, and fluviomarine bottom estuarine deposits
Slope: 0 to 1 percent
Mean Annual Air Temperature: 13.3 degrees C. (56 degrees F.)
Mean Annual Water Temperature: 13.9 degrees C. (57 degrees F.)
TAXONOMIC CLASS: Fine, mixed, subactive, nonacid, mesic Fluventic Sulfiwassents
TYPICAL PEDON: Coards silt loam, on permanently submerged fluviomarine bottom, <0.1 percent slope, under 190 centimeters of strongly saline water. (Colors are for moist soil unless otherwise noted.
A--0 to 2 inches (0 to 4 cm); dark gray (5Y 4/1) silt loam; massive; non-sticky; very fluid; abrupt boundary.
Ase--2 to 6 inches (4 to 15 cm); greenish black (10Y 2.5/1) silt loam; massive; very sticky; very fluid; sulfurous odor; clear boundary. (2 to 29 centimeter thick).
Cseg1--6 to 16 inches (15 to 42 cm); very dark greenish gray (10Y 3/1) silt loam; massive; moderately sticky; very fluid; 2 percent shell fragments; sulfurous odor; clear boundary.
Cseg2--16 to 32 inches (42 to 81 cm); very dark greenish gray (10Y 3/1) silty clay loam; massive; moderately sticky; very fluid; 3 percent olive (5Y 4/4) herbaceous fibers; sulfurous odor; clear boundary.
Cseg3--32 to 83 inches (81 to 210 cm); very dark greenish gray (10Y 4/1) silty clay loam; massive; very sticky; very fluid; sulfurous odor.
TYPE LOCATION: Worcester County, Maryland; approximately 4,900 feet south-southwest of Assacorkin Island and 11,044 feet east-northeast of the end of George Island Landing Road where it meets Parker Bay and approximately 10,130 feet north of the Maryland / Virginia state line in Chincoteague Bay, lat. 38 degrees 2 minutes 52.30 seconds N. long. 75 degrees 19 minutes 26.90 seconds W., NAD 83, USGS 7 minute Boxiron quadrangle.
RANGE IN CHARACTERISTICS:
Depth to Bedrock: Greater than 80 inches (200 centimeters)
Depth to Seasonal High Water Table: Permanently submersed
Depth to Sulfidic Materials: 0 to 20 inches (0 to 50 centimeters and a horizon at least 15 centimeters thick)
Manner of failure / fluidity class: Slightly to very fluid throughout
Shell Fragments: typically 0 to 5 percent by volume but could range up to 25 percent if a former historic oyster reef is encountered
Soil Reaction: Slightly alkaline to moderately alkaline throughout the profile
Oxidized reaction: Extremely or ultra acid
Electrical Conductivity: greater than 5.3 dS m-1
Salinity Class: Slightly to strongly saline
RANGE OF INDIVIDUAL HORIZONS:
A, Ag, Ase, or Aseg horizon:
Color--hue of 10Y, 10GY, 5GY, 5Y, 2.5Y or N, value of 2.5 to 4 moist, chroma of 0 to 2 with a dominant chroma of 1.
Texture--silty clay loam, silty clay, silt loam, clay, loam, fine sandy loam, sandy loam, loamy fine sand, or fine sand with mucky analogs
Consistence--non fluid to very fluid
Sulfurous odor and sulfidic materials are present.
Cseg horizon (some pedons may have 2Cseg horizons):
Color--hue of 10Y, 5GY, 10GY, N, 5Y, 2.5Y or 10YR value of 2 to 4 moist, chroma 0 to 2 but dominantly a chroma of 1.
Texture--silty clay loam, silt loam, clay loam, clay, or silty clay (not thick enough to dominate PSCS)
Consistence-moderately fluid to very fluid
Organic carbon ranges from 11.3 to 15.2 g kg-1.
Sulfurous odor and sulfidic materials are present.
COMPETING SERIES:
None
GEOGRAPHIC SETTING:
Landscape: Mid-Atlantic Coastal Plain Estuaries
Landform: Low-energy mainland coves, fluviomarine and lagoon bottoms
Parent Material: Fine mainland cove, lagoon bottom, and fluviomarine bottom estuarine deposits
Slope: 0 to 1 percent
Mean Annual Air Temperature: 10 to 13.9 degrees C. (50 to 57 degrees F.)
Mean Annual Water Temperature: 11.1 to 14.4 degrees C. (52 to 58 degrees F.)
Water Regime: Tidal, 1 to 4 feet tidal range
GEOGRAPHICALLY ASSOCIATED SOILS:
Pasture Point soils--are coarse-loamy and are on submerged wave-cut platforms.
Tingles soils--are fine-silty and have lower quantities of clay (<35%) and do not allow thick silty clay loam and silty clay layers.
Trappe soils--are sandy throughout and are on submerged wave-cut platforms.
Truitt soils--are fine-silty soils formed in estuarine deposits that have buried and preserved organic horizons below a depth of 40 inches (1 meter).
Tumagan soils--have organic horizons greater than within 16 inches (40 centimeters) of the soil surface.
Southpoint soils--are fine-silty soils formed in estuarine deposits of relict marsh sediments, and upland subaerial soils on mainland coves and submerged wave-cut headlands.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage Class: Subaqueous (permanently submersed)
Saturated Hydraulic Conductivity: Low to moderately low
Soil is permanently submerged with salt or brackish water. The presence of sulfidic material within 50 cm of the soil surface puts these soils at risk for acid sulfate drainage if they are dredged and exposed to the air.
USE AND VEGETATION:
Major Uses: Most areas are unvegetated and function as estuarine benthic wildlife habitat. Benthic fauna such as tubeworms are common. Benthic fauna such as clams, razor clams, juvenile blue crabs, scallops, oysters and juvenile finfish are rare.
Dominant Vegetation: Native vegetation includes rooted algae, eelgrass (Zostera marina) and Widgeon grass (Ruppia maritima). Vegetative coverage ranges from 0 to 5 percent.
SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Raleigh, North Carolina.
DISTRIBUTION AND EXTENT: Mid-Atlantic coastal lagoons and estuaries of Delaware (Indian River and Rehoboth Bays), Maryland (Chincoteague Bay), and possibly New Jersey (Barnegat Bay). This series is of small extent.
SERIES PROPOSED: Worcester County, Maryland, 2007. The name was taken and used from Danielle Balduff's dissertation for Chincoteague Bay, Maryland.
REMARKS: Diagnostic horizons and features in this pedon include:
Ochric epipedon--the zone from 0 to 6 inches (0 to 15 cm) (A and Ase horizons)
Peraquic feature--Positive soil water potential (permanently submerged) at the soil surface. (under 75 inches (190 cm) of salt water).
Particle size control section--The zone from 0 to 40 inches (0 to 100 cm) (the A, Ase and the Cseg horizons).
Sulfidic materials--a 6 inch (15 centimeter) thick horizon with 20 inches (50 centimeters) of the soil surface that contains sulfidic materials (the Ase, Cseg1 and Cseg2 horizons).
Fluidity Class--the zone from 0 to 83 inches (0 to 210 centimeters) is very fluid.
Fluventic feature--the soil organic carbon is greater than 0.2 percent at a depth of 50 inches (125 centimeters) below the soil surface.
ADDITIONAL DATA: Balduff, D.M. 2007 Ph.D. dissertation, University of Maryland.
NASIS user site and pedon ID: 2005MD047093.
NASIS Data Map Unit ID: 800940
National Cooperative Soil Survey
U.S.A.