Soil series profile
Medco soil series
Medco is a moderately well drained soil with a cobbly clay loam surface, mapped on 77,530 acres in 3 counties across 2 states. Hydrologic group D.
- Drainage class
- Moderately well drained 100% of mapped acres
- Hydrologic group
- D 100% of mapped acres
- Typical topsoil pH
- 7.0 neutral · range 7.0–7.0
- Mapped area
- 78k acres in 3 counties, 2 states
Typical Medco profile
Texture and pH by depth
Show as a table
| Depth | Texture | pH | Clay | Sand | Organic matter |
|---|---|---|---|---|---|
| 0–7 in (A1) | Cobbly clay loam | 7.0 | 31% | 35% | 4.5% |
| 7–12 in (A2) | Cobbly clay loam | 6.3 | 35% | 33% | 1.25% |
| 12–30 in (2Bw) | Clay | 5.6 | 55% | 17% | 0.25% |
| 30–40 in (3Cr) | Bedrock | Not reported | Not reported | Not reported | Not reported |
What this means
What Medco soil means for gardens, lawns and septic systems
For gardens
Typical topsoil in Medco soils is neutral: pH 7.0, the range most vegetables, flowers and lawn grasses prefer.
Loamy topsoil (loam, silt loam and similar) covers 96% of mapped Medco acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is cobbly clay loam (78% of mapped Medco acres).
100% of mapped Medco acres is moderately well to excessively drained, which suits most garden plants.
For lawns and yards
On 100% 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 100% 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 100% of the acres in mapped Medco 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 Medco soil is found
Mapped acres
Medco is mapped in Oregon and California.
| County | Acres | Share of county land |
|---|---|---|
| Jackson County, OR | 76,392 | 5.7% |
| Klamath County, OR | 30 | 0.0% |
| Siskiyou County, CA | 22 | 0.0% |
Septic absorption fields
NRCS rating, share of Medco acres
Show as a table
| Category | Share of acres |
|---|---|
| Not limited | 0.0% |
| Somewhat limited | 0.0% |
| Very limited | 100.0% |
Drainage, water table and flooding
Share of Medco acres
- Depth to seasonal high water table
- About 1.0 feet (12 in) (median where reported); within 18 inches on 100% of acres.
- Flooding
- Not mapped as flooding on most acres.
- Slope
- Typically 24–31% (median 31%).
- Topsoil organic matter
- Median 4.5%.
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 | 100.0% |
| 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 | 0.0% |
| C: slow infiltration | 0.0% |
| D: very slow infiltration (clayey, shallow or wet) | 100.0% |
| 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 Medco (component kind "Series") in SSURGO: 77,530 acres.
- Method
- Shares are by mapped acres of Medco components. The profile comes from the single largest Medco component. Full methodology.