LOCATION MARSHNECK RI CT MA NH NY

Established Series
Rev. MKP-JDT-DCP
09/2024

MARSHNECK SERIES

MLRA(s)--144A, 145, 149B
Depth class--Very deep
Drainage class--Subaqueous
Water depth range--2 to 252 centimeters
Parent materials--Coarse-loamy estuarine deposits
Geomorphic location-Flood-tidal deltas within coastal lagoons and estuaries
Slope range for series--0 to 2 percent
Mean annual air temperature--10 degrees C (50 degrees F)
Mean annual precipitation--1295 millimeters (51 inches)

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, nonacid, mesic Haplic Sulfiwassents

TYPICAL PEDON: Marshneck very fine sand on a flood-tidal delta, 1 percent slope under 80 centimeters of estuarine water. Tidal range is approximately 1 meter. (Colors are for moist soil unless otherwise noted).

Cseg1--0 to 5 centimeters; dark gray (2.5Y 4/1) very fine sand; structureless massive; nonsticky; nonplastic; nonfluid; 2 percent shell fragments; slight sulfurous odor; slight reaction to 30 percent hydrogen peroxide; neutral (pH 7.2); slightly acid (pH 6.4) oxidized pH; clear boundary.

Cseg2--5 to 27 centimeters; dark gray (2.5Y 4/1) very fine sand; structureless massive; nonsticky; nonplastic; nonfluid; 1 percent shell fragments; slight reaction to 30 percent hydrogen peroxide; slightly alkaline (pH 7.5); neutral (pH 6.7) oxidized pH; clear boundary.

Cseg3--27 to 69 centimeters; dark gray (2.5Y 4/1) very fine sand; structureless massive; nonsticky; nonplastic; nonfluid; slight reaction to 30 percent hydrogen peroxide; neutral (pH 7.2); extremely acid (pH 3.9) oxidized pH; clear boundary.

Cseg4--69 to 103 centimeters; 80 percent very dark gray (2.5Y 3/1) and 20 percent dark gray (2.5Y 4/1) loamy very fine sand; structureless massive; nonsticky; nonplastic; nonfluid; slight sulfurous odor; slight reaction to 30 percent hydrogen peroxide; neutral (pH 7.1); extremely acid (pH 3.5) oxidized pH; clear boundary.

Cseg5--103 to 144 centimeters; very dark gray (2.5Y 3/1) fine sandy loam; structureless massive; nonsticky; nonplastic; nonfluid; slight sulfurous odor; neutral (pH 7.3); extremely acid (pH 3.7) oxidized pH; clear boundary.

Cseg6--144 to 161 centimeters; very dark gray (2.5Y 3/1) loamy sand; structureless massive; nonsticky; nonplastic; nonfluid; 10 percent shell fragments; moderate sulfurous odor; slightly alkaline (pH 7.5); extremely acid (pH 3.7) oxidized pH; clear boundary.

Cseg7--161 to 200 centimeters; dark gray (2.5Y 4/1) loamy very fine sand; structureless massive; nonsticky; nonplastic; nonfluid; slight sulfurous odor; slight reaction to 30 percent hydrogen peroxide; slightly alkaline (pH 7.5); strongly acid (pH 5.4) oxidized pH.

TYPE LOCATION: New London County, Connecticut; Pattagansett River Estuary, about 101 meters (330 feet) west-northwest of Watts Island, approximately 331 meters (1,087 feet) southeast of the intersection of S. Bridebrook Road and Ridgewood Road, and approximately 744 meters (2,440 feet) northeast of Seal Rock, in the town of East Lyme; USGS topographic quadrangle: New London, CT

Latitude--41.2992611
Longitude-- -72.2243306
Datum--WGS84
Coordinates source--from hand-held GPS

RANGE IN CHARACTERISTICS:
Depth to bedrock--Greater than 200 centimeters
Soil moisture--Continuously inundated
Reaction throughout--Neutral to strongly alkaline (6.6 to 9.0)
Oxidized reaction--Ultra acid to extremely acid (pH 4.0) in one or combined horizons of at least 15 centimeters within 50 centimeters of the soil surface
Electrical conductivity (EC 1:5 water) throughout--0.6 dS/m or greater
Depth to hypersulfidic materials (incubated pH 4.0 or less)--0 to 50 centimeters
Shell fragments--0 to 50 percent, by volume in individual horizons (the weighted average in the particle-size control section would be 34 percent or less).
Rock fragments--0 to 70 percent gravels, by volume in individual horizons (the weighted average in the particle-size control section would be 34 percent or less).
Total Soil Organic Carbon Stocks 0 to 100 centimeters--3 to 17 kg m-2
Total Soil Organic Carbon Stocks 0 to 200 centimeters--10 to 30 kg m-2

Aseg or ACseg horizon (where present)
Hue--5GY, 10GY, 10Y, 10YR, 2.5Y, 5Y, or N
Value--2 to 6
Chroma--0 to 2
Texture--very fine sand, fine sand, loamy fine sand, very fine sandy loam, sandy loam, or silt loam
Organic matter content--0.5 to 6.0 percent
Clay content--0 to 8 percent
Manner of failure / fluidity--nonfluid to very fluid
Rock fragments (gravel)--0 to 10 percent, by volume
Organic carbon density--2 to 19 kg m-3

Cseg, Cg, C'seg, or C''seg horizon (where present)
Hue--2.5Y, 5Y, 5GY, 10GY, 10Y, 10YR, or N
Value--2.5 to 6
Chroma--0 to 2
Texture--very fine sand, loamy very fine sand, very fine sandy loam, silt loam, sandy loam, loamy sand, sand, or coarse sand
Organic matter content--0.5 to 4.0 percent
Clay content--0 to 8 percent
Manner of failure / fluidity class--nonfluid, slightly fluid, or moderately fluid
Rock fragments (gravel)--0 to 70 percent gravels, by volume
Some pedons contain one or multiple buried Ag or Aseg horizons
Organic carbon density--2 to 17 kg m-3

COMPETING SERIES: Fort Neck, Hammock, and Thames are competing series.
Fort Neck soils--in shallow mainland coves or lagoon bottoms and may include glacial parent materials below estuarine deposits
Hammock soils--on submerged mainland beaches and bay bottoms within sounds, and developed in marine deposits
Thames soils--are within river channels and on shoals in tidal rivers, and formed in subaqueous alluvium

GEOGRAPHIC SETTING:
Parent material-Coarse-loamy estuarine deposits
Landscape--Estuaries and lagoons
Landform-Flood-tidal delta flats
Slope--0 to 2 percent
Mean annual precipitation--1023 to 1320 millimeters (40 to 52 inches)
Mean annual air temperature--4 to 13 degrees C (39 to 55 degrees F)
Water salinity range--18 to 30 parts per thousand
Frost-free period--350 to 365 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are Alewife Cove, Massapog, and Pishagqua soils.
Alewife Cove soils--occur on flood-tidal deltas with higher water velocity and have coarser soil textures with higher amounts of gravel
Massapog soils--occur on sandy flood-tidal deltas and lack hypersulfidic materials
Pishagqua soils--in low-energy lagoon bottom and mainland cove landforms with higher amounts of clay.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--Subaqueous
Saturated hydraulic conductivity--High or very high
Soil moisture regime--Peraquic
Soil is continuously inundated with saline or brackish water.

USE AND VEGETATION:
Major uses--Areas of this soil are used for recreational fishing and swimming. Commercial uses include shell fishing and aquaculture. Wildlife use and benthic fauna associated with this soil includes tubeworms, clams, juvenile blue crabs, scallops, and juvenile finfish.
Native vegetation--This soil supports submerged aquatic vegetation and aquatic habitats. Some areas are vegetated with eelgrass (Zostera marina) and widgeon grass (Ruppia maritima)

DISTRIBUTION AND EXTENT:
General area--These soils are located along Connecticut, Massachusetts, New Hampshire, New York, and Rhode Island coasts.
Land Resource Regions--R - Northeastern Forage and Forest Region, S - Northern Atlantic Slope Diversified Farming Region
MLRA(s)--144A, 145, and 149B
Extent-Small

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Special Projects Office

SERIES ESTABLISHED: Washington County, Rhode Island, 2010.

REMARKS: This subaqueous soil series was mapped previously as water in the states listed above.

Diagnostic horizons and features in this pedon include--
Peraquic feature--Positive soil water potential (continuous inundation) at the soil surface (under 80 centimeters of brackish water).
Particle-size control section--The zone from 0 to 100 centimeters (0 to 40 inches) is coarse- loamy.
Hypersulfidic materials--The zone from 27 to 161 centimeters (Cseg3, Cseg4, Cseg5, and Cseg6 horizons) have oxidized reactions with pH values less than 4 after 16 weeks.
Haplic feature--The zone from 20 and 50 centimeters (Cseg2 and Cseg3 horizons) has a fluidity class of nonfluid.
Type location was moved to Connecticut as part of the Long Island Sound Coastal Zone Soil Survey in 2024, based on supporting laboratory analysis conducted at the University of Connecticut.
Taxonomic Version--Keys to Soil Taxonomy, 13th edition (2022)

ADDITIONAL DATA: Type location taken from S2022CT011091 in Pattagansett River Estuary, East Lyme, CT. Additional pedons used to determine ranges include S2000RI009002-NP, S2007RI009012-PJ, S2007RI009005-PJ, and S2006RI009015-QP (Sampled by the University of Rhode Island).

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National Cooperative Soil Survey
U.S.A.