Soil series profile
Rhoades soil series
Rhoades is a moderately well drained soil with a loam surface, mapped on 870,254 acres in 44 counties across 3 states. Hydrologic group D.
- Drainage class
- Moderately well drained 69% of mapped acres
- Hydrologic group
- D 77% of mapped acres
- Typical topsoil pH
- 6.5 slightly acidic · range 6.5–6.5
- Mapped area
- 870k acres in 44 counties, 3 states
Typical Rhoades profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–3 in (E) | Loam | 6.5 | 24% | 40% | 4% |
| 3–8 in (Btn) | Clay loam | 8.0 | 38% | 22% | 1.25% |
| 8–14 in (Btknyz) | Clay loam | 8.6 | 38% | 22% | 1.25% |
| 14–46 in (Bkyz) | Clay loam | 8.6 | 38% | 22% | 0.25% |
| 46–79 in (C) | Clay | 8.8 | 42% | 28% | 0.25% |
What this means
What Rhoades soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Rhoades soils is slightly acidic: pH 6.5, the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Rhoades acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is loam (83% of mapped Rhoades acres).
100% of mapped Rhoades acres is moderately well to excessively drained, which suits most garden plants.
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.
For a septic system
For conventional septic absorption fields, NRCS rates 16% of the acres in mapped Rhoades soils very limited, 83% somewhat limited and 1% not limited.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Rhoades soil is found
Mapped acres
Rhoades is mapped in South Dakota, North Dakota and Montana.
| County | Acres | Share of county land |
|---|---|---|
| Corson County, SD | 133,206 | 8.5% |
| Perkins County, SD | 106,820 | 5.8% |
| Ziebach County, SD | 91,069 | 7.2% |
| Bowman County, ND | 64,336 | 8.7% |
| Harding County, SD | 60,365 | 3.5% |
| Dunn County, ND | 47,100 | 3.7% |
| Morton County, ND | 42,496 | 3.5% |
| Dewey County, SD | 41,659 | 2.8% |
| Grant County, ND | 33,960 | 3.2% |
| Stark County, ND | 33,114 | 3.9% |
| Slope County, ND | 27,728 | 3.6% |
| Sioux County, ND | 23,231 | 3.3% |
| McKenzie County, ND | 22,331 | 1.3% |
| Emmons County, ND | 19,614 | 2.0% |
| Billings County, ND | 19,272 | 2.6% |
| Adams County, ND | 18,210 | 2.9% |
| Mercer County, ND | 17,389 | 2.6% |
| Glacier County, MT | 17,142 | 1.1% |
| Burleigh County, ND | 11,850 | 1.1% |
| Hettinger County, ND | 9,403 | 1.3% |
| Wibaux County, MT | 7,344 | 1.3% |
| Oliver County, ND | 7,323 | 1.6% |
| Golden Valley County, ND | 3,190 | 0.5% |
| Judith Basin County, MT | 2,989 | 0.3% |
| Williams County, ND | 1,911 | 0.1% |
| McLean County, ND | 1,404 | 0.1% |
| Meade County, SD | 976 | 0.0% |
| Mountrail County, ND | 971 | 0.1% |
| Brown County, SD | 965 | 0.1% |
| Logan County, ND | 757 | 0.1% |
| Fallon County, MT | 702 | 0.1% |
| McIntosh County, ND | 644 | 0.1% |
| Edmunds County, SD | 270 | 0.0% |
| Faulk County, SD | 163 | 0.0% |
| Pondera County, MT | 141 | 0.0% |
| Spink County, SD | 70 | 0.0% |
| Campbell County, SD | 66 | 0.0% |
| McPherson County, SD | 44 | 0.0% |
| LaMoure County, ND | 18 | 0.0% |
| Ward County, ND | 5 | 0.0% |
| Dickey County, ND | 4 | 0.0% |
| Stutsman County, ND | 2 | 0.0% |
| Walworth County, SD | 1 | 0.0% |
| Burke County, ND | 1 | 0.0% |
Septic absorption fields
NRCS rating, share of Rhoades acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 1.4% |
| Somewhat limited | 82.6% |
| Very limited | 16.0% |
Drainage, water table and flooding
Share of Rhoades acres
- Depth to seasonal high water table
- About 4.3 feet (51 in) (median where reported).
- Flooding
- Mapped as flooding on <1% of acres (<1% occasional, 0% frequent).
- Slope
- Typically 1–7% (median 3%).
- Topsoil organic matter
- Median 4%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 31.1% |
| Moderately well drained | 68.9% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
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 | 23.5% |
| D: very slow infiltration (clayey, shallow or wet) | 76.5% |
| 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 | 0.0% |
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 Rhoades (component kind "Series") in SSURGO: 870,254 acres.
- Method
- Shares are by mapped acres of Rhoades components. The profile comes from the single largest Rhoades component. Full methodology.