LOCATION CUDJOE                  FL

Established Series
Rev. GWH-MFV-AMS
12/2025

CUDJOE SERIES

MLRA(s): 156A
Soil Survey Regional Office (SSRO) Responsible: Auburn, Alabama
Depth Class: Shallow
Drainage Class: Very poorly drained
Saturated Hydraulic Conductivity: Moderately high to high in the solum and negligible in the rock material
Parent Material: Calcareous silty coastal marl materials over oolitic limestone bedrock
Slope: 0 to 1 percent
Elevation: -0.3 to 3 meters above mean sea level.
Mean Annual Air Temperature: 24 degrees C (75 degrees F.)
Mean Annual Precipitation: 1345 millimeters (53 inches)

TAXONOMIC CLASS: Loamy, carbonatic, isohyperthermic, shallow Typic Fluvaquents

TYPICAL PEDON: Cudjoe marly silt loam from a tidal swamp. (Colors are for moist soil unless otherwise stated.)

Lma1--0 to 23 centimeters (0 to 9 inches); light gray (10YR 7/1) marly silt loam, white (10YR 8/1), dry; weak coarse platy structure parting to weak fine subangular blocky; very friable, soft; slightly sticky, nonplastic; common fine and medium roots; common fine and very fine pores; strongly effervescent with 1N HCl; moderately alkaline (pH 8.0); clear smooth boundary.

Lma2--23 to 41 centimeters (9 to 16 inches); white (10YR 8/1) marly silt loam; weak coarse platy structure parting to weak fine subangular blocky; very friable, soft; slightly sticky, nonplastic; common fine roots; common fine and very fine pores; 5 percent gravel in lower 5 centimeters in the horizon; strongly effervescent with 1N HCl; moderately alkaline (pH 8.0); abrupt smooth boundary. (Combined thickness of the Lma horizons ranges from 25 to 50 centimeters)

2R--41 centimeters (16 inches); weakly to strongly cemented oolitic limestone bedrock; solution holes up to 100 centimeters) or more deep can be filled with sandy and/or loamy material.

TYPE LOCATION: Monroe County, Florida; Plantation Key; USGS quadrangle Plantation Key, FL.
Latitude: 24.9563198
Longitude: -80.5760345
Datum: WGS84
Estimated from other source

RANGE IN CHARACTERISTICS:
Solum thickness: 25 to 50 centimeters (10 to 20 inches)
Depth to seasonally high water table: 0 to 15 centimeters (0 to 6 inches)
Soil Reaction: Slightly alkaline to moderately alkaline throughout
Depth to limestone bedrock: 25 to 50 centimeters (10 to 20 inches)
Rock fragments: 0 to 10 percent throughout
Calcium carbonate equivalence: 40 to 90 percent or more
EC (mmhos/cm): 4 to 32 or more
Sodium Absorption Ratio: 15 to 60 percent or more
Exchangeable Sodium Percent: 13 to 60 percent or more
Particle-size control section (weighted averages):
Clay content: 5 to 40 percent
Carbonate Clay content: 3 to 30 percent
Silt content: 40 to 90 percent

Oa horizon, where present:
Color: Hue 5YR to 10YR, or Neutral; value 2 or 3; and chroma 1 or 2.
Texture: muck
von Post: H7 to H9
The Oa horizon is less than 8 centimeters (3 inches) thick.

Lma horizons:
Color: Hue 10YR or 2.5Y; value 3 to 8; and chroma 1 or 2.
Texture: marly silt loam, marly silt, marly silty clay loam, loam, or marly clay loam
2R horizon: weakly to strongly cemented oolitic limestone bedrock; solution holes up to 10 centimeters or more deep can be filled with sandy and/or loamy material.

COMPETING SERIES: This is the Biscayne and Saddlebunch series.
Biscayne soils: have greater than 15 percent rock fragments, have less than 90 percent calcium carbonate equivalence, occur in freshwater marshes, swamps, and low broad flats, are not impacted daily by tides.
Saddlebunch soils: are not very frequently flooded and occur on slightly higher landform positions with available water deeper in their soil profiles.

GEOGRAPHIC SETTING:
Landscape: Lower Coastal Plain
Landform(s): marine marshes, swamps, or low broad coastal flats in the tidal zone on the Key West Islands and/or along the southern coast of the Florida Peninsula
Parent material: Calcareous silty coastal marl materials over oolitic limestone bedrock
Slope: 0 to 1 percent
Elevation: -0.3 to 1.0 meters (-1.0 to 3 feet)
Mean annual temperature: 23 to 27 degrees C (73 to 81 degrees F)
Mean annual precipitation: 940 to 1570 millimeters (37 to 62 inches)
Frost-free period: 365 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Islamorda, Keylargo, Keyvaca, Keywest, Lignumvitae, Matacumbe, and Pennekamp soils:
Islamorada, Keylargo, and Tavernier soils: have control sections that contain highly decomposed organic material, occur in the tidal zone with mangroves, and occur on lower landform positions.
Keyvaca soils: have greater than 35 percent rock fragments throughout, have bedrock at depths less than 25 centimeters (10 inches), are better drained, and occur on higher landform positions.
Keywest soils: are stratified with sapric organic material and calcareous silty marl materials, occur in the tidal zone with mangroves, and occur on lower landform postions.
Lignumvitae soils have bedrock from 50 to less than 100 centimeters (20 to 40 inches), occur in the tidal zone with mangroves and are subject to very frequent flooding.
Matecumbe soils: have sapric organic materials, have bedrock at depths of less than 18 centimeters (7 inches), and occur on slightly higher landform positions.
Pennekamp soils: have less than 45 percent silt fraction, have highly decomposed organic materials at the soil surface, are better drained, and occur on higher landform positions.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class: Very poorly drained
Saturated hydraulic conductivity (KSAT): Moderately high to high
Runoff: High to very high
Depth to seasonal high-water table: 0 to 15 centimeters (0 to 6 inches)
Flooding frequency and duration: very frequent flooding with very brief duration caused by tides, storm surges, and hurricanes

USE AND VEGETATION:
Major uses: wildlife habitat and water quality.
Dominant vegetation: black mangrove, red mangrove, and white mangrove along with saltwort, glasswort, and poisonwood.

DISTRIBUTION AND EXTENT:
General area: Florida Everglades and associated areas
Land Resource Region: U - Florida Subtropical Fruit, Truck Crop, and Range Region
Major Land Resource Area: 156A
Extent: Small

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Auburn, Alabama.

SERIES ESTABLISHED: Monroe County, Florida, 1989.

REMARKS: These soils were formerly classified as Typic Fluvaquents and are revised here to the thirteenth edition of the keys (2022).
Diagnostic horizons and features recognized in this pedon:

Particle-size control section: 25 to 50 centimeters (10 to 20 inches)
Limnic soil materials: 0 to 41 centimeters (0 to 16 inches) (Lma1, Lma2 horizons)
Lithic contact: 41 centimeters (16 inches) (2R horizon)
Calcium Carbonate Equivalence: 40 to 95 percent or more
Aquic conditions: Endosaturation - 0 to 41 centimeters (0 to 16 inches)

ADDITIONAL DATA:
Laboratory data is available on the National Soil Survey website at: http://ncsslabdatamart.sc.egov.usda.gov/querypage.aspx

OSD User Site ID: S1988FL087006

OSD User Pedon ID: S1988FL087006

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National Cooperative Soil Survey
U.S.A.