Soil series profile
Clarno soil series
Clarno is a well drained soil with a loam surface, mapped on 1,149,153 acres in 27 counties across 2 states. Hydrologic group B.
- Drainage class
- Well drained 100% of mapped acres
- Hydrologic group
- B 98% of mapped acres
- Typical topsoil pH
- 6.7 neutral · range 6.7–6.7
- Mapped area
- 1.1M acres in 27 counties, 2 states
Typical Clarno profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–6 in (Ap) | Loam | 6.7 | 22% | 38% | 3% |
| 6–15 in (Bw) | Loam | 7.2 | 22% | 38% | 2% |
| 15–43 in (Bk) | Loam | 7.9 | 25% | 38% | 0.75% |
| 43–79 in (C) | Clay loam | 7.9 | 28% | 38% | 0.25% |
What this means
What Clarno soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Clarno soils is neutral: pH 6.7, the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Clarno acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is loam (>99% of mapped Clarno acres).
100% of mapped Clarno acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.
For a septic system
For conventional septic absorption fields, NRCS rates >99% of the acres in mapped Clarno soils very limited, <1% 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 Clarno soil is found
Mapped acres
Clarno is mapped in South Dakota and Nebraska.
| County | Acres | Share of county land |
|---|---|---|
| Hanson County, SD | 240,182 | 30.1% |
| Hutchinson County, SD | 240,182 | 30.1% |
| McCook County, SD | 113,348 | 30.9% |
| Miner County, SD | 86,522 | 24.8% |
| Yankton County, SD | 70,534 | 21.3% |
| Bon Homme County, SD | 66,235 | 18.3% |
| Sanborn County, SD | 64,296 | 17.7% |
| Turner County, SD | 59,298 | 15.0% |
| Kingsbury County, SD | 39,610 | 7.6% |
| Davison County, SD | 36,606 | 14.2% |
| Douglas County, SD | 31,142 | 11.2% |
| Jerauld County, SD | 26,604 | 7.8% |
| Aurora County, SD | 18,985 | 4.2% |
| Clay County, SD | 16,837 | 6.4% |
| Lake County, SD | 15,771 | 4.4% |
| Charles Mix County, SD | 11,037 | 1.6% |
| Minnehaha County, SD | 3,622 | 0.7% |
| Clark County, SD | 3,532 | 0.6% |
| Pierce County, NE | 2,368 | 0.6% |
| Stanton County, NE | 890 | 0.3% |
| Moody County, SD | 588 | 0.2% |
| Madison County, NE | 430 | 0.1% |
| Beadle County, SD | 408 | 0.1% |
| Hand County, SD | 60 | 0.0% |
| Brookings County, SD | 52 | 0.0% |
| Wayne County, NE | 8 | 0.0% |
| Spink County, SD | 7 | 0.0% |
Septic absorption fields
NRCS rating, share of Clarno acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.1% |
| Very limited | 99.9% |
Drainage, water table and flooding
Share of Clarno acres
- Depth to seasonal high water table
- None reported within about 6.5 feet (median where reported).
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 1–4% (median 1%).
- 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 | 100.0% |
| Moderately well drained | 0.0% |
| 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 | 98.0% |
| C: slow infiltration | 2.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| 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 | 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 Clarno (component kind "Series") in SSURGO: 1,149,153 acres.
- Method
- Shares are by mapped acres of Clarno components. The profile comes from the single largest Clarno component. Full methodology.