What's My Soil

A field guide to the soil under your feet

Soil series profile

Ontario soil series

Ontario is a well drained soil with a gravelly loam surface, mapped on 231,163 acres in 13 counties in NY. Hydrologic group B.

#1522 by mapped area fine-loamy Glossic Hapludalfs (Alfisols)

Drainage class
Well drained
100% of mapped acres
Hydrologic group
B
>99% of mapped acres
Typical topsoil pH
5.8
moderately acidic · range 5.8–5.8
Mapped area
231k
acres in 13 counties, 1 state

Typical Ontario profile

Texture and pH by depth

Typical Ontario soil profile by depth 0 in 20 in 40 in 60 in 0–8 in · Ap · pH 5.8 · 17% clay Gravelly loam 8–14 in · E · pH 5.8 · 17% clay Loam 14–21 in · Bt/E · pH 6.3 · 22% clay Loam 21–39 in · Bt · pH 7.0 · 22% clay Gravelly loam 39–48 in · C1 · pH 7.6 · 17% clay Gravelly loam 48–79 in · C2 · pH 7.6 · 17% clay Gravelly loam
Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).
Show as a table
Typical Ontario horizons (representative values)
Depth Texture pH Clay Sand Organic matter
0–8 in (Ap) Gravelly loam 5.8 17% 41% 3%
8–14 in (E) Loam 5.8 17% 41% 1.5%
14–21 in (Bt/E) Loam 6.3 22% 37% 1.5%
21–39 in (Bt) Gravelly loam 7.0 22% 37% 1.5%
39–48 in (C1) Gravelly loam 7.6 17% 41% 0.5%
48–79 in (C2) Gravelly loam 7.6 17% 41% 0.5%

Representative values from the most extensive Ontario map unit (Ontario gravelly loam, 3 to 8 percent slopes, survey area NY117). Other map units of this series vary within the series range.

Hands holding dark garden soil
Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Ontario soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Ontario soils is moderately acidic: pH 5.8. Many vegetables grow well here, and some gardens benefit from a little lime. Test before adding any.

Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Ontario acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is loam (60% of mapped Ontario acres).

100% of mapped Ontario 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 19% of the acres in mapped Ontario soils very limited, 81% 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.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Ontario soil is found

Mapped acres

Ontario is mapped in New York.

Counties with the most mapped Ontario soil
County Acres Share of county land
Wayne County, NY 57,107 14.8%
Monroe County, NY 36,794 8.8%
Genesee County, NY 29,641 9.4%
Cayuga County, NY 22,967 5.4%
Onondaga County, NY 19,979 4.0%
Ontario County, NY 19,207 4.7%
Livingston County, NY 16,268 3.8%
Seneca County, NY 7,263 3.5%
Orleans County, NY 6,526 2.6%
Niagara County, NY 5,933 1.8%
Yates County, NY 4,094 1.9%
Herkimer County, NY 3,413 0.4%
Madison County, NY 1,972 0.5%

Septic absorption fields

NRCS rating, share of Ontario acres

Not limited 0%
Somewhat limited 81%
Very limited 19%
Septic tank absorption field rating across mapped Ontario acres. Scale 0 to 100% of mapped land.
Show as a table
Septic tank absorption field rating across mapped Ontario acres.
CategoryShare of acres
Not limited0.0%
Somewhat limited81.2%
Very limited18.8%

Drainage, water table and flooding

Share of Ontario acres

Depth to seasonal high water table
About 2.5 feet (30 in) (median where reported).
Flooding
Not mapped as flooding on most acres.
Slope
Typically 5–28% (median 6%).
Topsoil organic matter
Median 3%.

Drainage class

Excessively drained 0%
Somewhat excessively drained 0%
Well drained 100%
Moderately well drained 0%
Somewhat poorly drained 0%
Poorly drained 0%
Very poorly drained 0%
Drainage class across mapped Ontario acres. Scale 0 to 100% of mapped land.
Show as a table
Drainage class across mapped Ontario acres.
CategoryShare of acres
Excessively drained0.0%
Somewhat excessively drained0.0%
Well drained100.0%
Moderately well drained0.0%
Somewhat poorly drained0.0%
Poorly drained0.0%
Very poorly drained0.0%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%
B: moderate infiltration >99%
C: slow infiltration <1%
D: very slow infiltration (clayey, shallow or wet) 0%
A/D: D as is, A if drained 0%
B/D: D as is, B if drained 0%
C/D: D as is, C if drained 0%
Hydrologic soil group across mapped Ontario acres. Scale 0 to 100% of mapped land.
Show as a table
Hydrologic soil group across mapped Ontario acres.
CategoryShare of acres
A: fast infiltration (mostly sandy or gravelly)0.0%
B: moderate infiltration99.8%
C: slow infiltration0.2%
D: very slow infiltration (clayey, shallow or wet)0.0%
A/D: D as is, A if drained0.0%
B/D: D as is, B if drained0.0%
C/D: D as is, C if drained0.0%

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 Ontario (component kind "Series") in SSURGO: 231,163 acres.
Method
Shares are by mapped acres of Ontario components. The profile comes from the single largest Ontario component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Ontario.