LOCATION LONGPOINT               MD+NJ

Established Series
CEP/DCS
10/2022

LONGPOINT SERIES

MLRA(s): 149A
Soil Survey Regional Office (SSRO) Responsible: Raleigh, North Carolina
Depth Class: Very deep
Drainage Class: Subaqueous (permanently submersed / continuously inundated)
Saturated Hydraulic Conductivity: High to very high in estuarine deposits, Moderately high to very high in pre-Holocene fluviomarine deposits
Parent Material: Coarse-loamy estuarine deposits and herbaceous organic material over fine-loamy, glauconitic fluviomarine deposits
Slope: 0 to 1 percent
Mean Annual Air Temperature: 55 degrees F. (13 degrees C)
Mean Annual Water Temperature: 53 degrees F. (12 degrees C)

TAXONOMIC CLASS: Fine-loamy, glauconitic, nonacid, mesic Typic Sulfiwassents

TYPICAL PEDON: Long Point loamy sand on a submerged tidal marsh landform with 1 percent slope under 0.5 meters of estuarine water in South River. (Colors are for moist soils unless otherwise noted).

Aseg--0 to 7 cm; greenish black (10Y 2.5/1) mucky loamy sand; single grain, loose; nonfluid; 20% organic fragments; strong hydrogen sulfide odor; extremely acid (pH 4.44), ultra acid (pH 2.13); color change with 3% hydrogen peroxide, slightly effervescent with 30% hydrogen peroxide; clear boundary.

Oese--7 to 20 cm; very dark brown (7.5YR 2.5/2) mucky peat; hemic soil material; von Post value of H5; 60% organic fragments; strong hydrogen sulfide odor; slightly alkaline (pH 7.37), strongly acid (pH 5.49) after 16 weeks; no color reaction with 3% hydrogen peroxide, non-effervescent with 30% hydrogen peroxide; clear boundary.

2Aseg--20 to 46 cm; greenish black (10Y 2.5/1) mucky fine sandy loam; massive; moderately fluid; 15% organic fragments; strong hydrogen sulfide odor; neutral (pH 7.34), extremely acid (pH 3.89) after 16 weeks; no color reaction with 3% hydrogen peroxide, non-effervescent with 30% hydrogen peroxide; clear boundary.

2Eseg--46 to 55 cm; greenish gray (10Y 5/1) fine sandy loam; massive; nonfluid; 15% organic fragments; slight hydrogen sulfide odor; slightly alkaline (pH 7.76), extremely acid (pH 3.62) after 16 weeks; no color reaction with 3% hydrogen peroxide, very slightly effervescent with 30% hydrogen peroxide; gradual boundary.

2Btseg1--55 to 69 cm; dark greenish gray (5GY 4/1) sandy clay loam; massive; slightly fluid; 2% distinct iron oxide concentrations; 10% organic fragments; slight hydrogen sulfide odor; neutral (pH 7.01), neutral (pH 6.68) after 16 weeks no color reaction with 3% hydrogen peroxide, very slightly effervescent with 30% hydrogen peroxide; clear boundary.

2Btseg2--69 to 86 cm; dark greenish gray (5G 4/1) clay; massive; nonfluid; 5% distinct brown (10YR 5/3) iron oxide concentrations; 5% organic fragments; no hydrogen sulfide odor; moderately alkaline (pH 7.91), strongly acid (pH 5.46) after 16 weeks; no color reaction with 3% hydrogen peroxide, slightly effervescent with 30% hydrogen peroxide; clear boundary.

2Btseg3--86 to 170 cm; dark grayish olive (10Y 4/2) sandy clay; massive; nonfluid; 2% distinct iron oxide concentrations; no hydrogen sulfide odor; neutral (pH 6.78), slightly acid after 16 weeks (pH 6.41); 5% gravels by volume; no color reaction with 3% hydrogen peroxide, strongly effervescent with 30% hydrogen peroxide.

TYPE LOCATION: Anne Arundel County, Maryland; South River, located in Selby Bay near Long Point, approximately 1,300 feet northwest of Long Point, 1,950 feet south of Mayo Point; USGS South River topographic quadrangle; latitude 38 degrees, 54 minutes, 52.77 seconds N; longitude 76 degrees, 30 minutes, 34.01 seconds W, WGS 1984; Major Land Resource Area 149A.

RANGE IN CHARACTERISTICS:
Depth to bedrock: Greater than 200 centimeters
Depth to seasonal high water table: Permanently submerged
Depth to hyper-sulfidic materials (incubated pH 4.0): 0 to 50 centimeters
Depth to Lithologic Discontinuity: 21 to 50 centimeters
Manner of Failure / Fluidity Class: nonfluid to moderately fluid throughout
Shell Fragments: 0 to 10 percent, by volume, throughout
Soil reaction: Very strongly acid to moderately alkaline throughout; oxidized reaction: ultra acid to strongly acid in the estuarine deposits, extremely acid to neutral in the fluviomarine Tertiary deposits (lithologic discontinuity)
Electrical Conductivity: greater than 1.5 dS / m-1 in estuarine deposits; less than 1 dS / m-1 in the Tertiary fluviomarine deposits by 1:5 by volume solution mixture
This soil contains up to 26% glauconite (pellets and clay-sized) in the fine-earth fraction. The glauconite percentage in the control section of the pedons range from 20-26%.

RANGE OF INDIVIDUAL HORIZONS:
Aseg horizon:
Color - hue 5Y, 10Y; value of 2.5 or 3; chroma of 1 or 2
Texture - loamy sand, sandy loam
Consistence - nonfluid or slightly fluid

Oe, Oese, or Oase horizon (if present):
Color - hue of 10YR or 7.5YR; value of 2, 2.5, or 3; chroma of 1 or 2
Texture - mucky peat or muck
Von Post Humification Scale - H1 to H6

2Aseg horizon (if present):
Color - hue of 10Y; value of 2.5 or 3; chroma of 1
Texture - sandy loam, mucky fine sandy loam
Consistence - nonfluid or moderately fluid

2Btseg or 2BCtg horizon:
Color - hue of 10YR, 5Y, 10Y, 5GY, 10GY or 5G; value of 3 or 4; and chroma of 1 or 2
Texture -sandy clay loam, sandy clay, clay
Consistence - nonfluid to moderately fluid

2CBseg horizon (if present):
Color - hue of 10YR, 10Y, or 10GY; values of 3 or 4; and chroma of 1 or 2
Texture - loamy sand, sandy loam, or sandy clay
Consistence - nonfluid

COMPETING SERIES: None.

GEOGRAPHIC SETTING:
Landscape: Northern Coastal Plain Estuaries
Landform: Submerged Tidal Marshes
Parent Material: Coarse-loamy estuarine deposits and herbaceous organic material over fine-loamy, glauconitic fluviomarine deposits
Slope: 0 to 1 percent
Mean Annual Air Temperature: 11 to 15 degrees C. (52 to 59 degrees F.)
Mean Annual Water Temperature: 10 to 16 degrees C. (50 to 60 degrees F.)Water Depth Range: 0 to 8 feet (0 to 2.5 meters)
Water Regime: Tidal, 0 to 2 feet (0 to 0.6 meters) tidal range
Water Salinity Range: 3 to 25 ppt

GEOGRAPHICALLY ASSOCIATED SOILS:
Broad Creek soils - fine-loamy soils which occur on Estuarine Tidal Creek Channel landforms; includes hypersulfidic materials and a buried A horizon.
Duvall Creek soils - sandy soils formed in stratified Holocene sands on submerged wave-built terrace landforms.
Hillsmere soils - fine-loamy soils which occur on Estuarine Channel and Mainland Cove landforms.
Overboard soils -fine-loamy soils occur on Tidal Creek Platform landforms; composed of fine fluid estuarine deposits overlying pre-Holocene Tertiary material; includes a buried A horizon and has greater than 15% glauconite by volume in the fine earth fraction.
South River soils -coarse-loamy soils occur on Wave-Cut Platform landforms; composed of sandy estuarine deposits overlying Tertiary fluviomarine material; has greater than 15% glauconite by volume in the fine earth fraction and horizons with chroma 3 or more between 15 and 100 cm.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage Class: Subaqueous drainage
Saturated Hydraulic Conductivity: High to very high in estuarine deposits, Moderately high to very high in pre-Holocene fluviomarine deposits
Soil Moisture Regime: Peraquic
Soil is permanently submerged / continuously inundated with brackish water. The presence of hypersulfidic materials within 50 cm of the soil surface puts these soils at severe risk for potential acid sulfate soil formation if they are dredged and exposed to the air.

USE AND VEGETATION:
Major Uses: Areas of this soil are used for recreational fishing, swimming, and boating. Commercial uses include shell fishing and aquaculture.
Dominant Vegetation: Benthic fauna such as clams, blue crabs, and oysters are associated with this soil. Eelgrass (Zostera marina), sea lettuce (Ulva sp.), and horned pondweed (Zannichellia palustris) may occur on these soils.

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Raleigh, North Carolina.

DISTRIBUTION AND EXTENT: Northern Atlantic Coastal Plain sub-estuaries of the western portion of the Chesapeake Bay and Atlantic Seaboard estuaries of the Northern Coastal Plain in New Jersey. MLRA 149A. This series is of small extent.

SERIES ESTABLISHED: Anne Arundel County, Maryland, 2022.

REMARKS: This subaqueous series is named for Long Point, a geomorphic feature of the Selby Bay located within the South River sub-estuary of Chesapeake Bay. Areas of Longpoint soils were formerly included and mapped as Water.

Diagnostic horizons and other diagnostic soil characteristics recognized in this pedon are (Keys to Soil Taxonomy, Twelfth Edition, 2012):
Ochric epipedon - the zone from 0 to 55 centimeters (Aseg, Oese, 2Aseg, and 2Eseg horizons)
Peraquic feature - the zone from 0 to 170 centimeters is permanently saturated
Hemic soil materials - the zone from 7 to 20 centimeters (Oese horizon)
Hyper-sulfidic materials - the zone from 20 to 46 centimeters incubated pH values less than 4.0 after 16 weeks (2Aseg horizon).
Lithologic Discontinuity - the zone from 20 to 170 centimeters (2Aseg, 2Eseg, 2Btseg1, 2Btseg2, 2Btseg3 horizons)
Albic horizon - the zone from 46 to 55 centimeters (2Eseg horizon)
Argillic horizon - the zone from 55 to 170 centimeters (2Btseg1, 2Btseg2, 2Btseg3 horizons)

ADDITIONAL DATA: Park, C.E., University of Maryland, Master of Science, 2021; thesis; Subaqueous Soils of South River, Maryland: Soil-Landscape Model Evaluation

Data Map Unit ID: 883190
NASIS user site and pedon ID: 2021MD003003

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National Cooperative Soil Survey
U.S.A.