Redwood National and State Parks, California
The most common soil here is Coppercreek, on about 15% of the land: a loam, a balanced mix that crumbles in your hand. Lackscreek and Slidecreek come next.
About 96% of the land drains well; groundwater comes within two feet of the surface under 4% of it.
USDA rates 99% of the land very limited for a standard septic drain field, and 96% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 2% of the land floods occasionally or more, and bedrock lies within 40 inches under 43% 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 Redwood National and State Parks, California, 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 Ultisols — strongly weathered soils with clay-enriched subsoils, common in warm humid climates. 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 Redwood National and State Parks, California. 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 |
|---|---|---|---|---|---|
| Coppercreek-Ahpah-Lackscreek complex, 30 to 50 percent slopes | 17K | Well drained | C | Very limited | Very limited |
| Sasquatch-Sisterrocks-Ladybird complex, 30 to 50 percent | 11K | Well drained | C | Very limited | Very limited |
| Ossagon-Squashan-Goldbluffs complex, 30 to 50 percent slopes | 10K | Well drained | C | Very limited | Very limited |
| Coppercreek-Slidecreek-Tectah complex, 30 to 50 percent slopes | 9K | Well drained | C | Very limited | Very limited |
| Slidecreek-Lackscreek-Coppercreek complex, 50 to 75 percent slopes | 8K | Well drained | C | Very limited | Very limited |
| Coppercreek-Slidecreek-Lackscreek complex, 30 to 50 percent slopes | 8K | Well drained | C | Very limited | Very limited |
| Coppercreek-Tectah-Slidecreek complex, 9 to 30 percent slopes | 5K | Well drained | C | Very limited | Very limited |
| Trailhead-Fortyfour complex, 30 to 50 percent slopes | 5K | Well drained | C | Very limited | Very limited |
| Ladybird-Stonehill complex, 30 to 50 percent | 4K | Well drained | C | Very limited | Very limited |
| Trailhead, 15 to 30 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Sidehill-Oakside-Darkwoods complex, 50 to 100 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Wiregrass-Rockysaddle complex, 30 to 50 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Devilscreek-Panthercreek-Coppercreek complex, 30 to 50 percent slopes | 4K | Well drained | C | Very limited | Very limited |
| Ossagon-Goldbluffs-Squashan complex, 9 to 30 percent slopes | 4K | Well drained | B | Very limited | Very limited |
| Bigtree-Mystery complex, 2 to 9 percent slopes | 3K | Well drained | B | Very limited | Very limited |
| Sisterrocks-Sasquatch-Footstep complex, 50 to 75 percent | 3K | Well drained | C | Very limited | Very limited |
| Atwell-Coppercreek complex, 30 to 50 percent slopes | 3K | Well drained | C | Very limited | Very limited |
| Wiregrass-Rockysaddle-Scaath complex, 30 to 50 percent slopes | 3K | Well drained | C | Very limited | Very limited |
| Pasturerock-Coyoterock-Maneze complex, 15 to 50 percent slopes | 3K | Well drained | C | Very limited | Very limited |
| Panthercreek-Devilscreek-Coppercreek complex, 50 to 75 percent slopes | 3K | 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, flood-prone areas. A geotechnical assessment is recommended before building.
Septic Systems
About 99% 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.