Soil series profile
Nassau soil series
Nassau is a somewhat excessively drained soil with a channery silt loam surface, mapped on 360,768 acres in 17 counties across 3 states. Hydrologic group D.
- Drainage class
- Somewhat excessively drained 98% of mapped acres
- Hydrologic group
- D 96% of mapped acres
- Typical topsoil pH
- 5.0 very strongly acidic · range 5.0–5.0
- Mapped area
- 361k acres in 17 counties, 3 states
Typical Nassau profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–9 in (H1) | Channery silt loam | 5.0 | 14% | 30% | 4% |
| 9–19 in (H2) | Very channery loam | 5.0 | 17% | 43% | 1% |
| 19–23 in (H3) | Unweathered bedrock | Not reported | Not reported | Not reported | Not reported |

What this means
What Nassau soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Nassau soils is very strongly acidic: pH 5.0. Most vegetables and lawn grasses do best around 6.0 to 7.0, so lime is often needed; blueberries, azaleas and rhododendrons like it as it is.
Loamy topsoil (loam, silt loam and similar) covers 96% of mapped Nassau acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is channery silt loam (74% of mapped Nassau acres).
98% of mapped Nassau acres is excessively or somewhat excessively drained: water moves through fast, so gardens need more frequent watering in dry spells.
For lawns and yards
On 96% 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 96% of the acres in mapped Nassau soils very limited, 0% somewhat limited and 0% not limited (4% not rated, such as urban land, pits or water).
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 Nassau soil is found
Mapped acres
Nassau is mapped in New York, New Jersey and Vermont.
| County | Acres | Share of county land |
|---|---|---|
| Washington County, NY | 88,366 | 16.6% |
| Columbia County, NY | 73,239 | 18.1% |
| Dutchess County, NY | 50,406 | 9.9% |
| Rensselaer County, NY | 29,024 | 7.0% |
| Ulster County, NY | 27,365 | 3.8% |
| Sussex County, NJ | 26,040 | 7.8% |
| Orange County, NY | 17,678 | 3.4% |
| Warren County, NJ | 11,898 | 5.2% |
| Schoharie County, NY | 10,061 | 2.5% |
| Greene County, NY | 7,255 | 1.8% |
| Saratoga County, NY | 5,433 | 1.1% |
| Herkimer County, NY | 4,429 | 0.5% |
| Albany County, NY | 3,599 | 1.1% |
| Addison County, VT | 3,226 | 0.7% |
| Jefferson County, NY | 1,730 | 0.2% |
| Schenectady County, NY | 1,017 | 0.8% |
| Montgomery County, NY | 2 | 0.0% |
Septic absorption fields
NRCS rating, share of Nassau acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 96.0% |
| Not rated | 4.0% |
Drainage, water table and flooding
Share of Nassau 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 9–38% (median 12%).
- Topsoil organic matter
- Median 4%.
Drainage class
Show as a table
| Category | Share of acres |
|---|---|
| Excessively drained | 0.0% |
| Somewhat excessively drained | 97.7% |
| Well drained | 0.0% |
| Moderately well drained | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
| Not rated | 2.3% |
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 | 0.4% |
| D: very slow infiltration (clayey, shallow or wet) | 95.6% |
| 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 | 4.0% |
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 Nassau (component kind "Series") in SSURGO: 360,768 acres.
- Method
- Shares are by mapped acres of Nassau components. The profile comes from the single largest Nassau component. Full methodology.