LOCATION PENNEKAMP               FL

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

PENNEKAMP SERIES

MLRA(s): 156A
Soil Survey Regional Office (SSRO) Responsible: Auburn Alabama
Depth Class: Shallow
Drainage Class: Moderately Well drained
Saturated Hydraulic Conductivity: High in the organic and loamy material and negligible in the rock material
Index Surface Runoff: High
Parent Material: Herbaceous organic material and loamy materials over oolitic limestone bedrock
Slope: 0 to 2 percent
Elevation: 1.5 to 4.5 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-skeletal, carbonatic, isohyperthermic Lithic Haprendolls

TYPICAL PEDON: Pennekamp gravelly muck on rises on a tropical hammock. (Colors are for moist soil unless otherwise stated.)

Oa--0 to 8 centimeters (0 to 3 inches); black (10YR 2/1) gravelly muck, very dark gray (10YR 3/1) dry; 15 percent fiber unrubbed and less than 5 percent rubbed; massive; very friable, soft; many fine, common medium, and few large roots throughout; 5 percent cobbles and 15 percent gravel; neutral (pH 7.3); abrupt smooth boundary. [2 to 10 centimeters (1 to 4 inches thick)]

A--8 to 20 centimeters (3 to 8 inches); very dark gray (5YR 3/1) very gravelly silt loam, dark reddish brown (5YR 3/2) dry; weak fine granular structure; very friable, soft; 50 percent gravel, 10 percent cobble; many fine and common medium roots throughout; neutral (pH 7.3); abrupt wavy boundary. [10 to 30 centimeters (4 to 12 inches thick)]

2R--20 centimeters (8 inches); weakly to strongly cemented oolitic limestone bedrock; solution holes up to 102 centimeters (40 inches) or more deep can be filled with sandy and/or marly material.

TYPE LOCATION: Monroe County, Florida; Key Largo USGS Blackwater Sound, FL quadrangle.
Latitude-- 25.1289749
Longitude-- -80.4086838
Datum--WGS84

RANGE IN CHARACTERISTICS:
Solum thickness: 25 to 50 centimeters (10 to 20 inches)
Depth to seasonally high water table: 106 to 152 centimeters (42 to 60 inches)
Soil Reaction: Moderately acid to slightly alkaline in the Oa horizon (pH 5.6 to 7.8) and neutral to moderately alkaline (pH 6.6 to 8.4) in the A horizon
Depth of mollic epipedon: 10 to 18 centimeters (4 to 7 inches) or more
Depth to limestone bedrock: 25 to 50 centimeters (10 to 20 inches)
Calcium carbonate equivalence: more than 40 percent in the loamy material
EC (mmhos/cm): 0 to 4
Sodium Absorption Ration: 0 to 5 percent
Exchangeable Sodium Percentage: 0 to 5 percent
Fiber content: Un-Rubbed: 5 to 70 percent; Rubbed less than 17 percent

Particle-size control section (weighted averages):
Clay content: 5 to 25 percent
Silt content: 45 to 60 percent
Very fine sand content: 2 to 10 percent

Oa horizon:
Hue: 10YR, 7.5YR, or 5YR
Value: 2 or 3 moist, 3 to 5 dry
Chroma: 1 to 3 moist, 1 to 3 or dry
Texture: muck or gravelly muck
Rock fragments: 5 to 25 percent

A horizon:
Hue: 10YR, 7.5YR, or 5YR
Value: 2 or 3 moist, 3 to 5 dry
Chroma: 1 to 3 moist, 1 to 3 or dry
Texture: very or extremely gravelly loam or silt loam
Rock fragments: 35 to 75 percent

R horizon: weakly to strongly cemented, oolitic limestone bedrock

COMPETING SERIES: This is the Keyvaca (FL) series.
Keyvaca soils have less than 45 percent silt formed from oolitic limestone and occur on lower positions.

GEOGRAPHIC SETTING:
Landscape: Lower Coastal Plain
Landform(s): rises on tropical hammocks on the Key West Islands
Parent material: Herbaceous organic material over loamy residuum from oolithic limestone bedrock
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:
Cudjoe and Saddlebunch soils are composed of silty marl, have less than 15 percent rock fragments, and occur on lower positions.
Islamorada soils have bedrock at depths greater than 51 centimeters (20 inches), are composed of sapric organic material, and occur in the tidal zone in lower positions.
Keylargo soils are composed of sapric organic sediments, have bedrock at depths greater than 130 centimeters (51 inches), and occur in the tidal zone in lower positions.
Keywest soils are stratified with sapric organic and silty marl sediments, have bedrock at depths of greater than 102 centimeters (40 inches), and occur in tidal swamps with mangroves.
Lignumvitae soils have bedrock at depths of more than 50 centimeters (20 inches), are composed of silty marl, and occur in the tidal zone swamps with mangroves.
Matecumbe soils have bedrock at depths less than 20 centimeters (8 inches) are composed of sapric organic materials and occur in lower positions.

DRAINAGE AND PERMEABILITY:
Drainage class: Moderate Well drained
Saturated hydraulic conductivity (KSAT): High
Runoff: High
Depth to seasonal high-water table: 106 to 152 centimeters (42 to 60 inches)
These soils are subject to rare flooding from storm surges and hurricanes.

USE AND VEGETATION:
Major uses: recreational and urban development.
Dominant vegetation: gumbo limbo, poisonwood, strangler fig, paradise tree, canella winterana, wild tamarind, and Deering's tree cactus.

DISTRIBUTION AND EXTENT: MLRA 156A Florida Everglades and Associated Areas.
Extent: limited

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

SERIES ESTABLISHED: Monroe County, Florida, 1989.

REMARKS: Diagnostic horizons and features recognized in this Pedon:

1. Particle-size control section: is less than 25 centimeters (10 inches)
2. Mollic epipedon - 0 to 20 centimeters (0 to 8 inches) (Oa, A horizon)
3. Lithic contact - 20 centimeters (8 inches) (2R horizon)

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: S1988FL087003

OSD User Pedon ID: S1988FL087003

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National Cooperative Soil Survey
U.S.A.