Soil series profile
Iuka soil series
Iuka is a moderately well drained soil with a loamy sand surface, mapped on 548,013 acres in 98 counties across 11 states. Hydrologic group C.
- Drainage class
- Moderately well drained 95% of mapped acres
- Hydrologic group
- C 75% of mapped acres
- Typical topsoil pH
- 5.6 moderately acidic · range 5.0–5.6
- Mapped area
- 548k acres in 98 counties, 11 states
Typical Iuka profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–5 in (H1) | Loamy sand | 5.6 | 6% | 85% | 0.75% |
| 5–30 in (H2) | Sandy loam | 5.0 | 13% | 67% | 0% |
| 30–66 in (H3) | Fine sandy loam | 5.0 | 10% | 67% | 0% |
What this means
What Iuka soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Iuka soils is moderately acidic: pH 5.6 (most land between 5.0 and 5.6). Many vegetables grow well here, and some gardens benefit from a little lime. Test before adding any.
Loamy topsoil (loam, silt loam and similar) covers 91% of mapped Iuka acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is fine sandy loam (54% of mapped Iuka acres).
98% of mapped Iuka acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
On 95% 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 36% 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 98% of the acres in mapped Iuka soils very limited, <1% somewhat limited and 0% not limited (1% 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.
Flooding is mapped on >99% of the acres (23% occasional, 75% frequent).
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Iuka soil is found
Mapped acres
Iuka is mapped in Alabama, Tennessee, Louisiana, Mississippi, Texas, Arkansas, Georgia, Virginia, Florida, Kentucky and District of Columbia. The 60 counties with the most Iuka acres:
| County | Acres | Share of county land |
|---|---|---|
| Monroe County, AL | 35,910 | 6.4% |
| Union Parish, LA | 23,810 | 4.2% |
| Clarke County, AL | 22,940 | 3.3% |
| McNairy County, TN | 22,623 | 6.3% |
| Barbour County, AL | 22,148 | 4.6% |
| Lincoln Parish, LA | 22,026 | 7.3% |
| Baldwin County, AL | 18,939 | 2.0% |
| Tuscaloosa County, AL | 17,304 | 2.4% |
| Choctaw County, AL | 16,528 | 3.2% |
| Marion County, AL | 13,970 | 3.5% |
| Newton County, TX | 13,883 | 2.3% |
| Claiborne Parish, LA | 13,718 | 2.8% |
| Crenshaw County, AL | 13,646 | 3.9% |
| Hardeman County, TN | 13,505 | 3.2% |
| Pike County, AL | 13,086 | 3.4% |
| Jasper County, TX | 12,186 | 2.0% |
| Wayne County, MS | 11,814 | 2.4% |
| Butler County, AL | 11,224 | 2.6% |
| Clarke County, MS | 11,196 | 2.6% |
| Bibb County, AL | 11,073 | 3.1% |
| Russell County, AL | 10,058 | 2.8% |
| Prentiss County, MS | 9,440 | 3.9% |
| Henry County, TN | 9,187 | 2.6% |
| Hale County, AL | 9,062 | 2.5% |
| Benton County, TN | 8,972 | 3.5% |
| Bullock County, AL | 8,774 | 2.5% |
| Hardin County, TN | 8,361 | 2.3% |
| Chester County, TN | 7,394 | 4.0% |
| De Soto Parish, LA | 7,392 | 1.3% |
| Greene County, MS | 7,244 | 1.6% |
| Franklin County, AL | 6,794 | 2.0% |
| Madison County, TN | 6,331 | 1.8% |
| Henderson County, TN | 6,028 | 1.8% |
| Perry County, AL | 5,958 | 1.5% |
| Marion County, GA | 5,614 | 2.4% |
| Montgomery County, AL | 5,539 | 1.3% |
| Marengo County, AL | 4,737 | 0.9% |
| Webster Parish, LA | 4,597 | 1.2% |
| Clark County, AR | 3,761 | 0.7% |
| Lamar County, AL | 3,722 | 1.1% |
| Franklin County, AR | 3,679 | 0.9% |
| Walthall County, MS | 3,641 | 1.4% |
| Decatur County, TN | 3,217 | 1.5% |
| Beauregard Parish, LA | 3,200 | 0.4% |
| Fayette County, AL | 3,181 | 0.9% |
| Cross County, AR | 2,862 | 0.7% |
| Lowndes County, AL | 2,825 | 0.7% |
| Bradley County, AR | 2,806 | 0.7% |
| Covington County, AL | 2,592 | 0.4% |
| Washington County, AL | 2,333 | 0.4% |
| Caldwell Parish, LA | 2,180 | 0.6% |
| Pike County, MS | 2,169 | 0.9% |
| Stafford County, VA | 2,009 | 1.3% |
| Tippah County, MS | 1,949 | 0.7% |
| Stewart County, GA | 1,899 | 0.7% |
| Kemper County, MS | 1,627 | 0.4% |
| Montgomery County, MS | 1,624 | 0.7% |
| Chattahoochee County, GA | 1,477 | 1.1% |
| Lincoln County, MS | 1,449 | 0.4% |
| Angelina County, TX | 1,380 | 0.3% |
Septic absorption fields
NRCS rating, share of Iuka acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.2% |
| Very limited | 98.4% |
| Not rated | 1.4% |
Drainage, water table and flooding
Share of Iuka acres
- Depth to seasonal high water table
- About 2.0 feet (24 in) (median where reported); within 18 inches on 36% of acres.
- Flooding
- Mapped as flooding on >99% of acres (23% occasional, 75% frequent).
- Slope
- Typically 0–1% (median 1%).
- Topsoil organic matter
- Median 1.2%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 3.3% |
| Moderately well drained | 94.7% |
| Somewhat poorly drained | 1.2% |
| Poorly drained | 0.6% |
| 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 | 3.8% |
| C: slow infiltration | 74.6% |
| D: very slow infiltration (clayey, shallow or wet) | 1.8% |
| A/D: D as is, A if drained | 12.5% |
| B/D: D as is, B if drained | 5.9% |
| C/D: D as is, C if drained | 0.0% |
| Not rated | 1.4% |
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 Iuka (component kind "Series") in SSURGO: 548,013 acres.
- Method
- Shares are by mapped acres of Iuka components. The profile comes from the single largest Iuka component. Full methodology.