LOCATION HILLSMERE MD+NJ

Established Series
CEP/DCS
10/2022

HILLSMERE 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: Moderately high to high
Parent Material: Fine-loamy, mixed estuarine 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, mixed, subactive, nonacid, mesic Fluventic Sulfiwassents

TYPICAL PEDON: Hillsmere silt loam on a permanently submerged southeast flowing estuarine channel landform with less than 1 percent slope under 4.5 meters of estuarine water. (Colors are for moist soil unless otherwise stated).

Aseg1--0 to 14 cm; greenish black (10Y 2.5/1) silt loam; massive; very fluid; slight petrochemical odor; ultra acid (pH 3.05), extremely acid (pH 3.57) after 16 weeks; color reaction with 3% hydrogen peroxide, strongly effervescent with 30% hydrogen peroxide; clear boundary.

Aseg2--14 to 45 cm; greenish black (10Y 2.5/1) silt loam; massive; very fluid; slight petrochemical odor; extremely acid (pH 4.36), ultra acid (pH 2.53) after 16 weeks; color reaction with 3% hydrogen peroxide, strongly effervescent with 30% hydrogen peroxide; clear boundary.

Cseg1--45 to 90 cm; very dark greenish gray (5GY 3/1) clay loam; massive; moderately fluid; slight petrochemical odor; slightly acid (6.38 pH), ultra acid (pH 3.14) after 16 weeks; color reaction with 3% hydrogen peroxide, strongly effervescent with 30% hydrogen peroxide; clear boundary.

Cseg2--90 to 151 cm; very dark greenish gray (10GY 3/1) silty clay; massive; moderately fluid; 1 percent shell fragments by volume; slight petrochemical odor; neutral (pH 7.06), ultra acid (pH 3.21) after 16 weeks; color reaction with 3% hydrogen peroxide, strongly effervescent with 30% hydrogen peroxide; gradual boundary.

Cseg3--151 to 200 cm; very dark greenish gray (10GY 3/1) loam; massive; moderately fluid; 1 percent shell fragments by volume; slight petrochemical odor; neutral (pH 7.26), ultra acid (pH 3.02) after 16 weeks; color reaction with 3% hydrogen peroxide, slightly effervescent with 30% hydrogen peroxide.

TYPE LOCATION: Anne Arundel County, Maryland; Glebe Bay in South River, approximately 3,500 feet southwest of Cedar Point and approximately 2,400 feet southwest of Larrimore Point and approximately 1,700 feet North of Glebe Heights, MD. USGS South River topographic quadrangle; latitude 38 degrees, 55 minutes, 49.11 seconds N. and longitude 76 degrees, 32 minutes, 14.35 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 submersed
Depth to hyper-sulfidic materials (incubated pH 4.0): 0 to 50 centimeters
Manner of Failure / Fluidity Class: slightly to very fluid throughout
Shell Fragments: 0 to 10 percent, by volume, throughout
Soil reaction: Ultra Acid to strongly alkaline; oxidized reaction: neutral to ultra acid throughout
Electrical Conductivity: greater than 1.0 dS / m-1 by 1:5 by volume solution mixture
Glauconite ranges from 0 to 15% by weight in the fine-earth fraction.

RANGE OF INDIVIDUAL HORIZONS:
Aseg horizon:
Color - hue N, 10Y, 5GY, or 10GY; value 2.5, 3, or 4; chroma 0 and 1
Texture - sandy loam, loam, silt loam, silty clay loam
Consistence - moderately fluid and very fluid
Cseg or Cg horizon:
Color - hue N, 5Y, 10Y, 5GY, 10GY, or 5G; value 2.5, 3, or 4; chroma 0 and 1
Texture - loam, clay loam, silt loam, silty clay loam, silty clay,
Consistence - slightly fluid, moderately fluid, very fluid

COMPETING SERIES:
Figgs soils - formed on lagoon bottom landforms in fine-loamy estuarine lagoonal deposits, do not contain glauconite, located within the Northern Tidewater Area, MLRA 153D.
Broad Creek soils (tentative) - fine-loamy soils occur on Estuarine Tidal Creek Channel landforms; composed of Holocene fine fluid estuarine deposits; includes a buried A horizon.

GEOGRAPHIC SETTING:
Landscape: Northern Coastal Plain estuaries
Landform: Estuarine Channels and Mainland Coves
Parent Material: Fine-loamy mixed estuarine deposits
Slope: 0 to 1 percent
Mean Annual Air Temperature: 52 to 59 degrees F. (11 to 15 degrees C.)
Mean Annual Water Temperature: 50 to 60 degrees F. (10 to 16 degrees C.)
Water Depth Range: 0 to 31 feet (0 to 9 meters)
Water Regime: Tidal, 0 to 2 feet (0 to 0.6 meters) tidal range
Water Salinity Range: 7 to 20 ppt

GEOGRAPHICALLY ASSOCIATED SOILS:
Duvall Creek soils - sandy soils formed in stratified Holocene sands on submerged wave-built terrace landforms.
Long Point soils - coarse-loamy soils occur on Submerged Tidal Marsh landforms; composed of sandy estuarine deposits and hemic organic material overlying lithologic discontinuity composed a relatively intact paleosol of Tertiary materials.
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: Moderately high to high
Soil Moisture Regime: Peraquic
Soil is permanently submerged / continuously inundated with brackish water. The presence of hyper-sulfidic materials within 50 cm of the soil surface puts these soils at 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 Monmouth County, NJ. MLRA 149A. This series is of small extent.

SERIES ESTABLISHED: Anne Arundel County, Maryland, 2022.

REMARKS: This subaqueous series is named for Hillsmere Shores a community located on the South River sub-estuary of Chesapeake Bay said to be where the South River meets the Chesapeake Bay. Areas of Hillsmere were formerly included with 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 45 centimeters (Aseg1 and Aseg2 horizons)
-Peraquic feature-the zone from 0 to 200 centimeters is permanently saturated
-Hyper-sulfidic materials-the zone from 0 to 200 centimeters incubated pH values less than 4.0 after 16 weeks.
-n Value greater than 0.7 - the zone from 0 to 200 centimeters with a moderately fluid to very fluid manner of failure.

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: 883186
NASIS user site and pedon ID: 2021MD003029

National Cooperative Soil Survey
U.S.A.