Union County Area, Oregon
The dominant drainage class is Well drained and the dominant hydrologic group is C (slow infiltration, moderate runoff). The most common soil order is Mollisols — grassland soils with a thick, dark, fertile topsoil rich in organic matter. 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 Union 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 |
|---|---|---|---|---|---|
| Tolo silt loam, 12 to 35 percent slopes | 62K | Well drained | C | Very limited | Very limited |
| Klicker stony silt loam, 2 to 40 percent slopes | 39K | Well drained | C | Very limited | Very limited |
| Klicker-Anatone complex, 5 to 40 percent slopes | 24K | Well drained | C | Very limited | Very limited |
| Hall Ranch stony loam, 2 to 35 percent slopes | 23K | Well drained | C | Very limited | Very limited |
| Gwinly very cobbly silt loam, 12 to 20 percent slopes | 23K | Well drained | D | Very limited | Very limited |
| Hot Lake silt loam | 22K | Somewhat poorly drained | C | Very limited | Very limited |
| Watama-Gwinly complex, 2 to 12 percent slopes | 19K | Well drained | C | Very limited | Very limited |
| Gwinly-Rockly complex, 5 to 40 percent slopes | 18K | Well drained | D | Very limited | Very limited |
| Lookingglass silt loam, 2 to 12 percent slopes | 16K | Moderately well drained | C | Very limited | Very limited |
| Starkey very stony silt loam, 2 to 35 percent slopes | 16K | Well drained | D | Very limited | Very limited |
| Gwinly very cobbly silt loam, 20 to 40 percent slopes | 15K | Well drained | D | Very limited | Very limited |
| La Grande silt loam | 15K | Moderately well drained | C | Very limited | Very limited |
| Olot stony silt loam, 12 to 35 percent slopes* | 14K | Well drained | C | Very limited | Very limited |
| Catherine silt loam | 14K | Somewhat poorly drained | C | Very limited | Very limited |
| Ukiah-Starkey complex, 5 to 40 percent slopes | 12K | Well drained | D | Very limited | Very limited |
| Imbler fine sandy loam, 1 to 5 percent slopes | 12K | Well drained | A | Not limited | Very limited |
| Anatone extremely stony loam, 2 to 35 percent slopes | 12K | Well drained | D | Very limited | Very limited |
| Gwinly-Rockly complex, 40 to 70 percent slopes | 10K | Well drained | D | Very limited | Very limited |
| Tolo silt loam, 35 to 65 percent slopes | 10K | Well drained | C | Very limited | Very limited |
| Klicker stony silt loam, 40 to 65 percent north slopes | 9K | Well drained | C | 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 96% of soils are rated "very limited" for dwellings with basements. Specific challenges include shallow bedrock, steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 100% 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.