Soil series profile
Ben Lomond soil series
Ben Lomond is a well drained soil with a sandy loam surface, mapped on 44,550 acres in 3 counties in CA. Hydrologic group A.
- Drainage class
- Well drained >99% of mapped acres
- Hydrologic group
- A >99% of mapped acres
- Typical topsoil pH
- 6.5 slightly acidic · range 5.2–6.5
- Mapped area
- 45k acres in 3 counties, 1 state
Typical Ben Lomond profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–19 in (H1) | Sandy loam | 6.5 | 14% | 67% | 1.5% |
| 19–46 in (H2) | Sandy loam | 5.6 | 14% | 67% | 0.75% |
| 46–59 in (H3) | Weathered bedrock | Not reported | Not reported | Not reported | Not reported |
What this means
What Ben Lomond soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Ben Lomond soils is slightly acidic: pH 6.5 (most land between 5.2 and 6.5), the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers >99% of mapped Ben Lomond acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is sandy loam (76% of mapped Ben Lomond acres).
>99% of mapped Ben Lomond acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
>99% of mapped acres is in hydrologic group A, where water soaks in fast. Lawns there dry out quickly; deeper, less frequent watering and organic matter help.
For a septic system
For conventional septic absorption fields, NRCS rates >99% of the acres in mapped Ben Lomond 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 Ben Lomond soil is found
Mapped acres
Ben Lomond is mapped in California.
| County | Acres | Share of county land |
|---|---|---|
| Santa Cruz County, CA | 34,208 | 12.5% |
| Santa Clara County, CA | 10,302 | 1.2% |
| San Mateo County, CA | 40 | 0.0% |
Septic absorption fields
NRCS rating, share of Ben Lomond 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 Ben Lomond 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 18–63% (median 40%).
- Topsoil organic matter
- Median 2%.
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 | 0.0% |
| Somewhat poorly drained | 0.0% |
| Poorly drained | 0.0% |
| Very poorly drained | 0.0% |
| Not rated | 0.3% |
Hydrologic soil group
Show as a table
| Category | Share of acres |
|---|---|
| A: fast infiltration (mostly sandy or gravelly) | 99.7% |
| 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 | 0.0% |
| B/D: D as is, B if drained | 0.0% |
| C/D: D as is, C if drained | 0.0% |
| Not rated | 0.3% |
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 Ben Lomond (component kind "Series") in SSURGO: 44,550 acres.
- Method
- Shares are by mapped acres of Ben Lomond components. The profile comes from the single largest Ben Lomond component. Full methodology.