LOCATION PAWCATUCK CT DE MA NH NJ NY

Established Series
Rev MFF-MT/BEF-CEP-DCP
02/2025

PAWCATUCK SERIES

MLRA(s)--144A, 145, 149A, 149B, and 153D
Depth class--Very deep
Drainage--Very poorly drained
Saturated hydraulic conductivity--Moderately high to very high in the organic layers; very high in the underlying mineral material
Parent material--Herbaceous organic deposits overlying sandy marine, estuarine, or glaciofluvial deposits
Geomorphic location--Tidal marshes within estuaries, coastal lowlands and barrier islands
Slope range for series--0 to 1 percent
Mean annual air temperature--10 degrees C (50 degrees F)
Mean annual precipitation--1143 millimeters (45 inches)

TAXONOMIC CLASS: Sandy or sandy-skeletal, mixed, euic, mesic Terric Sulfihemists

TYPICAL PEDON: Pawcatuck mucky peat - salt grass tidal marsh, undrained. (Colors are for moist soil, unless otherwise noted.)

Oese1--0 to 30 centimeters; very dark gray (10YR 3/1) mucky peat, dark grayish brown (10YR 4/2) dry; 65 percent fiber, 30 percent rubbed; H5 von Post humification; dense mat of roots, stems and leaves; slightly sticky; many very fine, fine and medium roots; fibers herbaceous; thin lenses and coatings of silt; 57 percent organic matter; total salts 19,500 ppm; slightly acid (pH 6.3), extremely acid (pH 3.9) oxidized pH; clear wavy boundary.

Oese2--30 to 102 centimeters; black (10YR 2/1) mucky peat, very dark gray (10YR 3/1) dry; 50 percent fiber, 25 percent rubbed; H5 von Post humification; slightly sticky; few very fine, fine and medium roots; fibers herbaceous; 54 percent organic matter; total salts 22,900 ppm; slightly acid (pH 6.3), very strongly acid (pH 4.8) oxidized pH; gradual wavy boundary.

Oese3--102 to 117 centimeters; black (10YR 2/1) moist and dry mucky peat; 40 percent fiber, 25 percent rubbed; H5 von Post humification; slightly sticky; fibers herbaceous; 27 percent organic matter; total salts 18,850 ppm; slightly acid (pH 6.3), extremely acid (pH 3.7) oxidized pH; clear wavy boundary. (Combined thickness of Oese horizons in 40 to 125 centimeters).

Cseg1--117 to 127 centimeters; gray (N 5/) very fine sandy loam, gray (10YR 5/1) dry; massive; friable; slightly sticky; 10 percent organic matter; total salts 20,000 ppm; slightly acid (pH 6.3), extremely acid (pH 4.0) oxidized pH; clear wavy boundary.

Cseg2--127 to 200 centimeters; black (10YR 2/1) loamy sand, dark gray (10YR 4/1) dry; single grain; loose; 10 percent gravel; total salts 20,000 ppm; slightly acid (pH 6.3), ultra acid (pH 2.8) oxidized pH. (Combined thickness of Cseg horizons is 20 to 75 centimeters).

TYPE LOCATION: New London County, Connecticut; town of Stonington, Barn Island area, 0.8 kilometers northeast of the elevation benchmark on Barn Island and 1.23 kilometers north of the elevation benchmark on Pawcatuck Point. USGS Quadrangle--Watch Hill, CT

Latitude--41.3341222
Longitude-- -71.8615500
Datum--WGS84
Coordinates source--handheld GPS

RANGE IN CHARACTERISTICS:
Depth to Bedrock--Greater than 200 centimeters
Thickness of Organic Deposits--40 to 130 centimeters
Soil moisture--Saturated; peraquic soil moisture regime
Reaction Throughout--Strongly acid to slightly alkaline (pH 5.1 to 7.8)
Oxidized Reaction Throughout--Ultra acid to strongly acid (pH 2.2 to 5.5)
Electrical Conductivity (EC 1:5 water) throughout--0.6 dS/m or greater
Total Soil Organic Carbon Stock 0 to 100 centimeters--10 to 53 kg m-2
Total Soil Organic Carbon Stock 0 to 200 centimeters--35 to 76 kg m-2
Thin layers of silt and very fine sand are common in the organic horizons.

Oese, Oe, Oase, Oa, Oise, or Oi horizons (where present)
Hue--5YR to 5Y, or neutral
Value--2 to 5
Chroma--0 to 3
Texture--typically hemic materials; range includes fibric and sapric materials
Von post humification scale--H2 to H9
Organic carbon density--23 to 66 kg m-3

Cseg or Cg horizons
Hue--10YR to 5BG
Value--2 to 7
Chroma--0 to 3
Texture--loamy sand or sand; some pedons have finer-textured sub-horizons but the weighted average texture class is sandy
Organic carbon density--8 to 54 kg m-3
Coarse fragments--0 to 25 percent gravels, by volume
Shell fragments and herbaceous fibers are common.

COMPETING SERIES: There are no other soils currently in this family.

GEOGRAPHIC SETTING:
Parent Material--Herbaceous organic deposits overlying sandy marine, estuarine or glaciofluvial deposits
Landscape--Estuaries, coastal lowlands, and barrier islands
Landform--Tidal marshes
Slope--0 to 2 percent
Mean Annual Precipitation--1000 to 1300 millimeters (39 to 51 inches)
Mean Annual Air Temperature--7 to 13 degrees C (45 to 55 degrees F)
Frost-free Period--350 to 365 days

GEOGRAPHICALLY ASSOCIATED SOILS:
These are the Calves, Hammonasset, Ipswich, Matunuck, Quinnipiac, and Westbrook soils.
Calves soils--formed in loamy estuarine deposits overlying loamy or sandy alluvium and include a histic epipedon
Hammonasset soils--formed in thick deposits of highly decomposed herbaceous organic materials and are found on tidal marshes within coastal lowlands
Ipswich soils--formed in deposits of moderately decomposed herbaceous organic materials deeper than 130 centimeters and found on tidal marshes within coastal lowlands
Matunuck soils--are mineral soils and have an organic surface layer less than 40 centimeters thick
Quinnipiac soils--formed in loamy alluvium or estuarine deposits with no histic epipedon and are found on tidal marshes within coastal lowlands, estuaries, and tidal rivers
Westbrook soils--formed in partially decomposed herbaceous organic material overlying loamy marine, estuarine or glaciofluvial deposits

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage Class--Very poorly drained
Saturated Hydraulic Conductivity--Moderately high to very high in the organic layers; very high in the underlying mineral material
Soil Moisture Regime--Peraquic
Flooding Frequency--Twice daily by tides in addition to periodic riverine flooding at times

USE AND VEGETATION:
Major Uses--Most areas are in salt marsh and provide food and habitat for fish, shellfish and wildfowl.
Vegetation--Small scattered areas are in saltgrass hay. The most common grasses are salt meadowgrass, salt water grass and spike grass. Other vegetation includes blackgrass, sea lavender, saltwort, seaside goldenrod, aster, and purple gerardi. In areas where the 1:5 EC by volume is below 1.5 dS/m, vegetation consists principally of tall reeds and sedges.

DISTRIBUTION AND EXTENT:
General Area--Coastal areas and tidally influenced rivers of Connecticut, Massachusetts, Delaware, New Hampshire, New Jersey, and New York
Land Resource Regions--R - Northeastern Forage and Forest Region, S - Northern Atlantic Slope Diversified Farming Region, and T - Atlantic and Gulf Coast Lowland Forest and Crop Region
MLRA(s)--144A, 145, 149A, 149B, and 153D
Extent-Moderate

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

SERIES ESTABLISHED: New London County, Connecticut, 1977.

REMARKS: This revision reflects general updating, reformatting, and inclusion of blue carbon data. Pawcatuck soils have been mapped as Tidal marsh, undifferentiated. Some of the Pawcatuck soils were classified and mapped at the Great Group or Subgroup level. Pawcatuck series was originally described as consisting of fibric organic materials. Current procedures for estimating fibers indicate that the materials are dominantly hemic. These soils become extremely acid when drained.

The lab and/or field method for total salts in the Typical Pedon is not known but is retained for historical purposes. Total salt content previously reported in the RIC is generally more than 10,000 ppm, but total salt content ranges from 1,000 to 40,000 ppm.

Diagnostic horizons and features in this pedon include:
1. Histosols--have organic materials that total 40 centimeters or more between the soil surface and a depth of 50 centimeters - the zone from a depth of 0 to 117 centimeters (Oese horizons).
2. Hypersulfidic materials--the zone from 0 to 200 centimeters;
3. Reaction (pH value) is more than 4.5 throughout the control section.

ADDITIONAL DATA: Type location taken from 2008CT011008 in Stonington, CT.

Additional support pedons used to develop this series include 1987NY059008, 1994NH015016, 1998NJ025001, 2004NJ033001, 2011CT011002, 2011CT011004, S2015NJ029024, S2016RI009010, S2019NH015006, S2019RI009002, S2022MD047112, 2023CT011227, and 2023CT011261.

Refer to publication "Tidal Marshes of Connecticut and Rhode Island," Hill, D. E. and Shearin, A. E., Connecticut Agricultural Experiment Station Bulletin 709, Feb. 1970.

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National Cooperative Soil Survey
U.S.A.