Soil series profile
Wyola soil series
Wyola is a well drained soil with a silty clay loam surface, mapped on 694,392 acres in 55 counties across 4 states. Hydrologic group C.
- Drainage class
- Well drained >99% of mapped acres
- Hydrologic group
- C >99% of mapped acres
- Typical topsoil pH
- 7.0 neutral · range 6.4–7.0
- Mapped area
- 694k acres in 55 counties, 4 states
Typical Wyola profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–6 in (Ap) | Silty clay loam | 6.4 | 32% | 16% | 3% |
| 6–14 in (Bt1) | Silty clay | 7.2 | 42% | 18% | 2% |
| 14–21 in (Bt2) | Silty clay loam | 7.7 | 38% | 18% | 1.25% |
| 21–46 in (Bk) | Silty clay loam | 8.0 | 34% | 17% | 0.75% |
| 46–79 in (C) | Silty clay loam | 8.0 | 37% | 16% | 0.25% |
What this means
What Wyola soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Wyola soils is neutral: pH 7.0 (most land between 6.4 and 7.0), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 98% of mapped Wyola acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silty clay loam (64% of mapped Wyola acres).
>99% of mapped Wyola acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
On >99% 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 >99% of the acres in mapped Wyola 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.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Wyola soil is found
Mapped acres
Wyola is mapped in North Dakota, Montana, South Dakota and Wyoming.
| County | Acres | Share of county land |
|---|---|---|
| Hettinger County, ND | 59,770 | 8.2% |
| Morton County, ND | 48,865 | 4.0% |
| Grant County, ND | 36,358 | 3.4% |
| Big Horn County, MT | 35,617 | 0.8% |
| Dunn County, ND | 31,096 | 2.4% |
| Perkins County, SD | 30,448 | 1.7% |
| Judith Basin County, MT | 30,076 | 3.3% |
| Stark County, ND | 29,244 | 3.4% |
| Adams County, ND | 29,206 | 4.6% |
| Corson County, SD | 28,193 | 1.8% |
| McKenzie County, ND | 27,890 | 1.6% |
| Sioux County, ND | 23,449 | 3.4% |
| Fergus County, MT | 21,090 | 0.8% |
| Roosevelt County, MT | 18,150 | 1.2% |
| Sheridan County, MT | 17,242 | 1.6% |
| Ziebach County, SD | 17,186 | 1.4% |
| Richland County, MT | 16,684 | 1.2% |
| Glacier County, MT | 16,549 | 1.0% |
| Chouteau County, MT | 13,723 | 0.5% |
| Blaine County, MT | 12,761 | 0.5% |
| Bowman County, ND | 12,415 | 1.7% |
| Slope County, ND | 12,072 | 1.6% |
| Sheridan County, WY | 11,747 | 0.7% |
| Mercer County, ND | 10,288 | 1.5% |
| Wibaux County, MT | 10,135 | 1.8% |
| Billings County, ND | 9,945 | 1.4% |
| Williams County, ND | 7,260 | 0.5% |
| Daniels County, MT | 7,123 | 0.8% |
| Emmons County, ND | 6,120 | 0.6% |
| Mountrail County, ND | 5,857 | 0.5% |
| McCone County, MT | 5,710 | 0.3% |
| Oliver County, ND | 5,565 | 1.2% |
| Toole County, MT | 5,466 | 0.5% |
| Fallon County, MT | 4,637 | 0.4% |
| Rosebud County, MT | 4,629 | 0.1% |
| Harding County, SD | 4,322 | 0.3% |
| Valley County, MT | 4,042 | 0.1% |
| Burleigh County, ND | 3,527 | 0.3% |
| Phillips County, MT | 3,507 | 0.1% |
| Golden Valley County, ND | 3,400 | 0.5% |
| Custer County, MT | 2,211 | 0.1% |
| Pondera County, MT | 2,003 | 0.2% |
| Park County, MT | 1,872 | 0.1% |
| Dewey County, SD | 1,332 | 0.1% |
| Campbell County, SD | 971 | 0.2% |
| Musselshell County, MT | 932 | 0.1% |
| McIntosh County, ND | 878 | 0.1% |
| Dawson County, MT | 875 | 0.1% |
| Liberty County, MT | 740 | 0.1% |
| Logan County, ND | 597 | 0.1% |
| McLean County, ND | 397 | 0.0% |
| Hill County, MT | 100 | 0.0% |
| Golden Valley County, MT | 96 | 0.0% |
| Johnson County, WY | 19 | 0.0% |
| Yellowstone County, MT | 2 | 0.0% |
Septic absorption fields
NRCS rating, share of Wyola acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 99.9% |
| Not rated | 0.1% |
Drainage, water table and flooding
Share of Wyola acres
- Depth to seasonal high water table
- About 4.9 feet (59 in) (median where reported).
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 1–5% (median 4%).
- Topsoil organic matter
- Median 3%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 99.7% |
| Moderately well drained | 0.2% |
| 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 | 99.2% |
| D: very slow infiltration (clayey, shallow or wet) | 0.7% |
| 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% |
| Not rated | 0.1% |
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 Wyola (component kind "Series") in SSURGO: 694,392 acres.
- Method
- Shares are by mapped acres of Wyola components. The profile comes from the single largest Wyola component. Full methodology.