Soil series profile
Tawas soil series
Tawas is a very poorly drained soil with a muck surface, mapped on 727,968 acres in 70 counties across 3 states. Hydrologic group A/D.
- Drainage class
- Very poorly drained >99% of mapped acres
- Hydrologic group
- A/D 87% of mapped acres
- Typical topsoil pH
- 6.3 slightly acidic · range 5.5–6.3
- Mapped area
- 728k acres in 70 counties, 3 states
Typical Tawas profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–8 in (Oa1) | Muck | 6.3 | Not reported | Not reported | 80% |
| 8–18 in (Oa2) | Muck | 6.1 | Not reported | Not reported | 82% |
| 18–27 in (Oa3) | Muck | 6.1 | Not reported | Not reported | 85% |
| 27–79 in (Cg) | Sand | 5.7 | 1% | 94% | 0.25% |
What this means
What Tawas soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Tawas soils is slightly acidic: pH 6.3 (most land between 5.5 and 6.3), the range most vegetables, flowers and lawn grasses prefer.
Organic muck or peat is the most common topsoil (>99% of mapped Tawas acres). It is rich and holds water, but is often wet, can be acidic, and settles when drained. The most common surface texture is muck (92% of mapped Tawas acres).
>99% of mapped Tawas acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.
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.
A seasonal high water table comes within 18 inches of the surface on >99% 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 >99% of the acres in mapped Tawas 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 Tawas soil is found
Mapped acres
Tawas is mapped in Michigan, Minnesota and Wisconsin. The 60 counties with the most Tawas acres:
| County | Acres | Share of county land |
|---|---|---|
| Marquette County, MI | 74,629 | 5.9% |
| Delta County, MI | 33,834 | 4.5% |
| Schoolcraft County, MI | 32,861 | 4.4% |
| Menominee County, MI | 32,018 | 4.9% |
| Beltrami County, MN | 31,626 | 2.0% |
| Chippewa County, MI | 31,462 | 3.2% |
| Lake of the Woods County, MN | 31,409 | 3.8% |
| Luce County, MI | 29,758 | 5.2% |
| Roscommon County, MI | 26,426 | 7.9% |
| Cheboygan County, MI | 25,691 | 5.6% |
| Mackinac County, MI | 23,197 | 3.6% |
| Alger County, MI | 22,932 | 3.9% |
| Montmorency County, MI | 19,553 | 5.6% |
| Alpena County, MI | 18,896 | 5.2% |
| Presque Isle County, MI | 18,006 | 4.3% |
| Itasca County, MN | 17,720 | 1.0% |
| Missaukee County, MI | 16,185 | 4.5% |
| Lake County, MI | 14,600 | 4.0% |
| Emmet County, MI | 13,578 | 4.5% |
| Kalkaska County, MI | 13,174 | 3.7% |
| Alcona County, MI | 13,000 | 3.0% |
| Otsego County, MI | 12,947 | 3.9% |
| Iosco County, MI | 11,838 | 3.4% |
| Montcalm County, MI | 11,574 | 2.6% |
| Wexford County, MI | 11,336 | 3.1% |
| Antrim County, MI | 11,169 | 3.7% |
| Crawford County, MI | 9,671 | 2.7% |
| Ogemaw County, MI | 9,103 | 2.5% |
| Charlevoix County, MI | 8,983 | 3.3% |
| Keweenaw County, MI | 8,944 | 2.5% |
| Roseau County, MN | 8,212 | 0.8% |
| Iron County, MI | 6,598 | 0.9% |
| Bayfield County, WI | 6,082 | 0.6% |
| Arenac County, MI | 5,963 | 2.5% |
| Price County, WI | 5,666 | 0.7% |
| Houghton County, MI | 5,596 | 0.9% |
| Osceola County, MI | 5,111 | 1.4% |
| Clearwater County, MN | 4,904 | 0.8% |
| Sawyer County, WI | 4,820 | 0.6% |
| Oscoda County, MI | 4,737 | 1.3% |
| Mecosta County, MI | 4,320 | 1.2% |
| Washburn County, WI | 3,721 | 0.7% |
| Gladwin County, MI | 2,920 | 0.9% |
| Muskegon County, MI | 2,904 | 0.9% |
| Ashland County, WI | 2,636 | 0.4% |
| Ionia County, MI | 2,345 | 0.6% |
| Douglas County, WI | 2,186 | 0.3% |
| Ontonagon County, MI | 1,976 | 0.2% |
| Gogebic County, MI | 1,896 | 0.3% |
| Marinette County, WI | 1,738 | 0.2% |
| Isabella County, MI | 1,048 | 0.3% |
| Grand Traverse County, MI | 1,042 | 0.4% |
| Iron County, WI | 979 | 0.2% |
| Newaygo County, MI | 908 | 0.2% |
| Baraga County, MI | 641 | 0.1% |
| Clare County, MI | 577 | 0.2% |
| Dickinson County, MI | 451 | 0.1% |
| Oneida County, WI | 437 | 0.1% |
| Oconto County, WI | 333 | 0.1% |
| Vilas County, WI | 285 | 0.1% |
Septic absorption fields
NRCS rating, share of Tawas acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 99.7% |
| Not rated | 0.3% |
Drainage, water table and flooding
Share of Tawas acres
- Depth to seasonal high water table
- About 0 inches (median where reported); within 18 inches on >99% of acres.
- Flooding
- Mapped as flooding on 1% of acres (0% occasional, 1% frequent).
- Slope
- Typically 0–1% (median 0%).
- Topsoil organic matter
- Median 80%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 0.0% |
| Well drained | 0.0% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 99.7% |
| Not rated | 0.3% |
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 | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 0.0% |
| A/D: D as is, A if drained | 86.6% |
| B/D: D as is, B if drained | 13.1% |
| C/D: D as is, C if drained | 0.0% |
| Not rated | 0.3% |
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 Tawas (component kind "Series") in SSURGO: 727,968 acres.
- Method
- Shares are by mapped acres of Tawas components. The profile comes from the single largest Tawas component. Full methodology.