Linn County Area, Oregon
The most common soil here is Honeygrove, on about 5% of the land: a paragravelly silty clay loam, smooth and slightly sticky. Dayton and Kinney come next.
About 66% of the land drains well, and 21% stays wet for long stretches; groundwater comes within two feet of the surface under 24% of it.
USDA rates 96% of the land very limited for a standard septic drain field, and 88% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 10% of the land floods occasionally or more, and bedrock lies within 40 inches under 34% of it.
Soils change over short distances, so look up an address below for the soil at that exact spot and the reasons behind each rating.
The soils you're most likely standing on
The biggest named soils in Linn County Area, Oregon, each drawn five feet deep from its official USDA description, in its recorded colors.
Dots mark gravel; white flecks mark lime. Shares are by acres across the survey area, and each mapped patch usually mixes several of these soils.
The biggest mapped areas
The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). The most common soil order is Inceptisols — young soils with minimal horizon development but more than Entisols. This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in Linn County Area, Oregon. Search your address to find the exact soil composition, drainage, and series details at your specific location.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Dayton silt loam | 58K | Poorly drained | D | Very limited | Very limited |
| Honeygrove silty clay loam, 12 to 25 percent slopes | 32K | Well drained | C | Very limited | Very limited |
| Harrington-Klickitat complex, 50 to 75 percent south slopes | 31K | Well drained | B | Very limited | Very limited |
| Woodburn silt loam, 0 to 3 percent slopes | 29K | Moderately well drained | C | Very limited | Very limited |
| Amity silt loam | 26K | Somewhat poorly drained | C/D | Very limited | Very limited |
| Bashaw silty clay | 25K | Poorly drained | D | Very limited | Very limited |
| Harrington-Klickitat complex, 50 to 75 percent north slopes | 17K | Well drained | B | Very limited | Very limited |
| Keel gravelly silt loam, 45 to 75 percent slopes | 17K | Well drained | C | Very limited | Very limited |
| Holcomb silt loam | 17K | Somewhat poorly drained | D | Very limited | Very limited |
| Honeygrove silty clay loam, 25 to 50 percent south slopes | 16K | Well drained | C | Very limited | Very limited |
| Coburg silty clay loam | 15K | Moderately well drained | C | Very limited | Very limited |
| Water | 14K | Not rated | Not rated | ||
| Newberg fine sandy loam | 14K | Well drained | A | Very limited | Very limited |
| Blachly clay loam, 3 to 30 percent slopes | 12K | Well drained | C | Very limited | Very limited |
| Malabon silty clay loam | 12K | Well drained | C | Somewhat limited | Very limited |
| Keel gravelly silt loam, 25 to 45 percent slopes | 11K | Well drained | C | Very limited | Very limited |
| Nekia silty clay loam, 2 to 12 percent slopes | 11K | Well drained | C | Very limited | Very limited |
| Chehalis silty clay loam | 11K | Well drained | B | Very limited | Very limited |
| Concord silt loam | 11K | Poorly drained | C/D | Very limited | Very limited |
| Kinney-Klickitat complex, 50 to 70 percent south slopes | 11K | Well drained | B | Very limited | Very limited |
Soil Orders in This Area
The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.
What This Means
Building & Foundations
About 88% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 96% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.
Gardening & Agriculture
Well-drained soils on sloped terrain — good for most plants but watch for erosion. Terracing, contour planting, and mulching help retain moisture and topsoil. Drip irrigation is more effective than sprinklers on slopes.