Soil series profile

Croatan soil series

Croatan is a very poorly drained soil with a muck surface, mapped on 413,786 acres in 35 counties across 4 states. Hydrologic group B/D.

#744 by mapped area loamy Terric Haplosaprists (Histosols)

Drainage class
Very poorly drained
100% of mapped acres
Hydrologic group
B/D
78% of mapped acres
Typical topsoil pH
4.5
very strongly acidic · range 3.2–4.5
Mapped area
414k
acres in 35 counties, 4 states

Typical Croatan profile

Texture and pH by depth

Typical Croatan soil profile by depth 0 in 20 in 40 in 60 in 0–28 in · Oa · pH 4.5 Muck 28–33 in · Ag · pH 4.0 · 15% clay Mucky sandy loam 33–60 in · Cg1 · pH 4.0 · 25% clay Sandy clay loam 60–80 in · Cg2 · pH 4.0 · 5% clay Loamy sand
Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).
Show as a table
Typical Croatan horizons (representative values)
Depth Texture pH Clay Sand Organic matter
0–28 in (Oa) Muck 4.5 Not reported Not reported 42.5%
28–33 in (Ag) Mucky sandy loam 4.0 15% 68% 12%
33–60 in (Cg1) Sandy clay loam 4.0 25% 60% 2.75%
60–80 in (Cg2) Loamy sand 4.0 5% 80% 0%

Representative values from the most extensive Croatan map unit (Croatan muck, ponded, 0 to 2 percent slopes, survey area NC141). Other map units of this series vary within the series range.

Hands holding dark garden soil
Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Croatan soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Croatan soils is very strongly acidic: pH 4.5 (most land between 3.2 and 4.5). Most vegetables and lawn grasses do best around 6.0 to 7.0, so lime is often needed; blueberries, azaleas and rhododendrons like it as it is.

Organic muck or peat is the most common topsoil (100% of mapped Croatan acres). It is rich and holds water, but is often wet, can be acidic, and settles when drained. The most common surface texture is muck (90% of mapped Croatan acres).

100% of mapped Croatan acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.

For lawns and yards

On 100% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.

A seasonal high water table comes within 18 inches of the surface on 100% of mapped acres, often in spring. Basements, sump pumps and lawns in low spots feel it first.

For a septic system

For conventional septic absorption fields, NRCS rates 100% of the acres in mapped Croatan soils very limited, 0% somewhat limited and 0% not limited.

Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.

Flooding is mapped on 32% of the acres (0% occasional, 17% frequent).

Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Croatan soil is found

Mapped acres

Croatan is mapped in North Carolina, Florida, Georgia and Mississippi.

Counties with the most mapped Croatan soil
County Acres Share of county land
Pender County, NC 50,318 10.1%
Jones County, NC 36,589 13.2%
Onslow County, NC 28,890 6.5%
Calhoun County, FL 27,137 7.5%
Brunswick County, NC 24,777 4.9%
Ware County, GA 23,889 4.5%
Craven County, NC 21,524 5.4%
Jackson County, MS 19,959 4.9%
Charlton County, GA 19,872 4.4%
Carteret County, NC 18,076 5.9%
Columbus County, NC 17,978 3.3%
Bladen County, NC 16,549 3.2%
Liberty County, FL 12,392 2.3%
Cumberland County, NC 10,669 2.9%
Beaufort County, NC 10,210 2.1%
Gulf County, FL 8,178 2.0%
Clinch County, GA 6,864 1.4%
Pamlico County, NC 6,026 3.1%
Taylor County, FL 5,924 0.9%
Pearl River County, MS 5,259 1.1%
Nassau County, FL 5,243 1.3%
Union County, FL 5,237 3.3%
Duplin County, NC 5,121 1.1%
Escambia County, FL 4,795 1.1%
Bradford County, FL 4,437 2.4%
Stone County, MS 4,297 1.6%
Screven County, GA 3,856 1.1%
Perry County, MS 2,386 0.6%
Wakulla County, FL 1,998 0.5%
Marion County, MS 1,868 0.6%
Lamar County, MS 1,566 0.5%
Robeson County, NC 1,420 0.2%
Echols County, GA 188 0.1%
Martin County, NC 177 0.1%
Brantley County, GA 118 0.0%

Septic absorption fields

NRCS rating, share of Croatan acres

Not limited 0%
Somewhat limited 0%
Very limited 100%
Septic tank absorption field rating across mapped Croatan acres. Scale 0 to 100% of mapped land.
Show as a table
Septic tank absorption field rating across mapped Croatan acres.
CategoryShare of acres
Not limited0.0%
Somewhat limited0.0%
Very limited100.0%

Drainage, water table and flooding

Share of Croatan acres

Depth to seasonal high water table
About 0 inches (median where reported); within 18 inches on 100% of acres.
Flooding
Mapped as flooding on 32% of acres (0% occasional, 17% frequent).
Slope
Typically 0–1% (median 1%).
Topsoil organic matter
Median 42.5%.

Drainage class

Excessively drained 0%
Somewhat excessively drained 0%
Well drained 0%
Moderately well drained 0%
Somewhat poorly drained 0%
Poorly drained 0%
Very poorly drained 100%
Drainage class across mapped Croatan acres. Scale 0 to 100% of mapped land.
Show as a table
Drainage class across mapped Croatan acres.
CategoryShare of acres
Excessively drained0.0%
Somewhat excessively drained0.0%
Well drained0.0%
Moderately well drained0.0%
Somewhat poorly drained0.0%
Poorly drained0.0%
Very poorly drained100.0%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%
B: moderate infiltration 0%
C: slow infiltration 0%
D: very slow infiltration (clayey, shallow or wet) 2%
A/D: D as is, A if drained 21%
B/D: D as is, B if drained 78%
C/D: D as is, C if drained 0%
Hydrologic soil group across mapped Croatan acres. Scale 0 to 100% of mapped land.
Show as a table
Hydrologic soil group across mapped Croatan acres.
CategoryShare of acres
A: fast infiltration (mostly sandy or gravelly)0.0%
B: moderate infiltration0.0%
C: slow infiltration0.0%
D: very slow infiltration (clayey, shallow or wet)1.6%
A/D: D as is, A if drained20.6%
B/D: D as is, B if drained77.8%
C/D: D as is, C if drained0.0%

Sources & data dates

Source
USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
Data date
SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
Scope
All map unit components named Croatan (component kind "Series") in SSURGO: 413,786 acres.
Method
Shares are by mapped acres of Croatan components. The profile comes from the single largest Croatan component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Croatan.