Soil series profile
Savannah soil series
Savannah is a moderately well drained soil with a fine sandy loam surface, mapped on 1,692,470 acres in 103 counties across 7 states. Hydrologic group C.
- Drainage class
- Moderately well drained >99% of mapped acres
- Hydrologic group
- C 51% of mapped acres
- Typical topsoil pH
- 4.6 very strongly acidic · range 4.5–5.3
- Mapped area
- 1.7M acres in 103 counties, 7 states
Typical Savannah profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–10 in (H1) | Fine sandy loam | 4.6 | 10% | 69% | 1.75% |
| 10–31 in (H2) | Sandy clay loam | 4.6 | 25% | 57% | 0.25% |
| 31–64 in (H3) | Sandy clay loam | 4.6 | 25% | 57% | 0.25% |
What this means
What Savannah soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Savannah soils is very strongly acidic: pH 4.6 (most land between 4.5 and 5.3). 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.
Loamy topsoil (loam, silt loam and similar) covers 98% of mapped Savannah acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (67% of mapped Savannah acres).
>99% of mapped Savannah acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
On 98% 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.
For a septic system
For conventional septic absorption fields, NRCS rates 98% of the acres in mapped Savannah soils very limited, 0% somewhat limited and 0% not limited (2% not rated, such as urban land, pits or water).
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.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Savannah soil is found
Mapped acres
Savannah is mapped in Mississippi, Arkansas, Louisiana, Alabama, Tennessee, Virginia and Texas. The 60 counties with the most Savannah acres:
| County | Acres | Share of county land |
|---|---|---|
| Washington Parish, LA | 97,448 | 22.8% |
| Winn Parish, LA | 75,210 | 12.4% |
| St. Tammany Parish, LA | 68,275 | 12.5% |
| Smith County, MS | 61,936 | 15.5% |
| Jones County, MS | 58,309 | 13.7% |
| Dallas County, AL | 54,641 | 10.3% |
| Rankin County, MS | 48,025 | 10.5% |
| Simpson County, MS | 43,780 | 12.3% |
| Calhoun County, AR | 43,278 | 10.8% |
| Scott County, MS | 42,326 | 11.0% |
| Pickens County, AL | 40,026 | 7.7% |
| Marion County, MS | 38,106 | 11.5% |
| Jefferson County, AR | 36,325 | 6.5% |
| Caldwell Parish, LA | 36,060 | 10.7% |
| Cleveland County, AR | 34,899 | 9.2% |
| Franklin County, AL | 33,442 | 9.7% |
| Dallas County, AR | 32,968 | 7.9% |
| Bradley County, AR | 32,809 | 7.9% |
| Decatur County, TN | 32,794 | 15.3% |
| Saline County, AR | 31,094 | 6.8% |
| Lincoln County, AR | 28,693 | 8.0% |
| Marion County, AL | 27,998 | 6.9% |
| Pike County, MS | 27,599 | 11.2% |
| Monroe County, MS | 26,676 | 5.6% |
| Sumter County, AL | 26,642 | 5.5% |
| Lowndes County, MS | 26,102 | 8.3% |
| Drew County, AR | 25,597 | 4.8% |
| Hempstead County, AR | 25,345 | 5.5% |
| Wayne County, MS | 24,842 | 5.1% |
| Clark County, AR | 23,782 | 4.3% |
| Washington County, AR | 23,137 | 3.8% |
| Winston County, MS | 22,979 | 6.0% |
| Prentiss County, MS | 22,094 | 9.1% |
| Choctaw County, AL | 22,072 | 4.3% |
| Lamar County, AL | 21,179 | 6.0% |
| Ashley County, AR | 20,965 | 3.6% |
| Covington County, MS | 20,762 | 8.2% |
| Noxubee County, MS | 18,525 | 4.3% |
| Jasper County, MS | 17,401 | 4.2% |
| Newton County, MS | 16,362 | 4.8% |
| Greene County, AL | 16,299 | 4.8% |
| Oktibbeha County, MS | 15,921 | 5.7% |
| Kemper County, MS | 13,710 | 3.5% |
| Union Parish, LA | 13,441 | 2.4% |
| Ouachita Parish, LA | 13,322 | 3.5% |
| Itawamba County, MS | 13,198 | 3.9% |
| Lauderdale County, MS | 12,873 | 3.4% |
| LaSalle Parish, LA | 11,196 | 2.7% |
| Tishomingo County, MS | 11,117 | 4.2% |
| Hale County, AL | 11,014 | 3.1% |
| Chester County, TN | 10,861 | 5.9% |
| Jefferson Davis County, MS | 10,670 | 4.5% |
| Clarke County, MS | 9,904 | 2.3% |
| Leake County, MS | 8,440 | 2.3% |
| Neshoba County, MS | 7,528 | 2.2% |
| Walthall County, MS | 7,346 | 2.9% |
| Marengo County, AL | 6,813 | 1.2% |
| Spotsylvania County, VA | 6,676 | 3.0% |
| Fayette County, AL | 6,527 | 1.9% |
| Greene County, MS | 5,944 | 1.3% |
Septic absorption fields
NRCS rating, share of Savannah acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 98.2% |
| Not rated | 1.8% |
Drainage, water table and flooding
Share of Savannah acres
- Depth to seasonal high water table
- About 2.0 feet (24 in) (median where reported); within 18 inches on 14% of acres.
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 1–7% (median 3%).
- Topsoil organic matter
- Median 1.8%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 0.0% |
| Moderately well drained | 99.9% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
| Not rated | 0.1% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 0.0% |
| B: moderate infiltration | 0.0% |
| C: slow infiltration | 51.3% |
| D: very slow infiltration (clayey, shallow or wet) | 1.0% |
| A/D: D as is, A if drained | 0.0% |
| B/D: D as is, B if drained | 0.0% |
| C/D: D as is, C if drained | 46.0% |
| Not rated | 1.8% |
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 Savannah (component kind "Series") in SSURGO: 1,692,470 acres.
- Method
- Shares are by mapped acres of Savannah components. The profile comes from the single largest Savannah component. Full methodology.