Soil series profile
Clarion soil series
Clarion is a well drained soil with a loam surface, mapped on 958,155 acres in 56 counties across 2 states. Hydrologic group B.
- Drainage class
- Well drained >99% of mapped acres
- Hydrologic group
- B >99% of mapped acres
- Typical topsoil pH
- 6.2 slightly acidic · range 6.2–6.2
- Mapped area
- 958k acres in 56 counties, 2 states
Typical Clarion profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–9 in (Ap) | Loam | 6.2 | 21% | 45% | 3.5% |
| 9–14 in (A) | Loam | 6.2 | 21% | 45% | 2.5% |
| 14–33 in (Bw) | Loam | 6.6 | 21% | 45% | 0.75% |
| 33–79 in (C) | Loam | 8.0 | 15% | 49% | 0.25% |
What this means
What Clarion soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Clarion soils is slightly acidic: pH 6.2, the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Clarion acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is loam (>99% of mapped Clarion acres).
100% of mapped Clarion 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 3% of the acres in mapped Clarion soils very limited, 98% somewhat limited and 0% not limited.
Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.
Where Clarion soil is found
Mapped acres
Clarion is mapped in Iowa and Minnesota.
| County | Acres | Share of county land |
|---|---|---|
| Dallas County, IA | 106,874 | 28.5% |
| Story County, IA | 87,737 | 24.0% |
| Hardin County, IA | 80,379 | 22.2% |
| Boone County, IA | 68,621 | 18.8% |
| Polk County, IA | 67,534 | 18.4% |
| Greene County, IA | 62,819 | 17.2% |
| Carroll County, IA | 52,909 | 14.5% |
| Franklin County, IA | 49,884 | 13.4% |
| Guthrie County, IA | 30,963 | 8.2% |
| Palo Alto County, IA | 23,623 | 6.6% |
| Kossuth County, IA | 23,509 | 3.8% |
| Sac County, IA | 21,073 | 5.7% |
| Nobles County, MN | 17,043 | 3.7% |
| Winnebago County, IA | 15,619 | 6.1% |
| Calhoun County, IA | 15,263 | 4.2% |
| Cerro Gordo County, IA | 14,475 | 4.0% |
| Dickinson County, IA | 12,982 | 5.4% |
| Buena Vista County, IA | 12,273 | 3.3% |
| Emmet County, IA | 12,209 | 4.8% |
| Martin County, MN | 11,738 | 2.6% |
| Freeborn County, MN | 11,443 | 2.5% |
| Hamilton County, IA | 11,427 | 3.1% |
| Cottonwood County, MN | 11,229 | 2.7% |
| Webster County, IA | 11,121 | 2.4% |
| Wright County, IA | 11,014 | 3.0% |
| Marshall County, IA | 10,488 | 2.9% |
| Pocahontas County, IA | 8,563 | 2.3% |
| Jasper County, IA | 8,527 | 1.8% |
| Clay County, IA | 7,377 | 2.0% |
| Hancock County, IA | 7,182 | 2.0% |
| Faribault County, MN | 6,554 | 1.4% |
| Jackson County, MN | 6,473 | 1.4% |
| Humboldt County, IA | 5,963 | 2.1% |
| Renville County, MN | 5,647 | 0.9% |
| Nicollet County, MN | 5,143 | 1.8% |
| Murray County, MN | 4,866 | 1.1% |
| Osceola County, IA | 4,447 | 1.7% |
| Sibley County, MN | 4,386 | 1.2% |
| Brown County, MN | 4,279 | 1.1% |
| Steele County, MN | 4,010 | 1.5% |
| Waseca County, MN | 3,987 | 1.5% |
| Blue Earth County, MN | 3,870 | 0.8% |
| McLeod County, MN | 3,768 | 1.2% |
| Worth County, IA | 3,762 | 1.5% |
| Watonwan County, MN | 2,239 | 0.8% |
| Scott County, MN | 1,392 | 0.6% |
| Meeker County, MN | 495 | 0.1% |
| Chippewa County, MN | 260 | 0.1% |
| Carver County, MN | 173 | 0.1% |
| Redwood County, MN | 128 | 0.0% |
| Rice County, MN | 115 | 0.0% |
| Yellow Medicine County, MN | 104 | 0.0% |
| Le Sueur County, MN | 96 | 0.0% |
| Wright County, MN | 56 | 0.0% |
| Lac qui Parle County, MN | 48 | 0.0% |
| Lincoln County, MN | 0 | 0.0% |
Septic absorption fields
NRCS rating, share of Clarion acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 97.5% |
| Very limited | 2.5% |
Drainage, water table and flooding
Share of Clarion 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 3–8% (median 4%).
- Topsoil organic matter
- Median 3.5%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 99.5% |
| Moderately well drained | 0.5% |
| 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 | 99.5% |
| C: slow infiltration | 0.5% |
| 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 Clarion (component kind "Series") in SSURGO: 958,155 acres.
- Method
- Shares are by mapped acres of Clarion components. The profile comes from the single largest Clarion component. Full methodology.