El Yunque National Forest, Puerto Rico
The dominant drainage class is Well drained and the dominant hydrologic group is B/D (varies with drainage). 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 El Yunque National Forest, Puerto Rico.
| Soil Map Unit | Acres | Drainage | Hydro Group | Dwellings | Septic |
|---|---|---|---|---|---|
| Zarzal-Cristal complex, 20 to 60 percent slopes | 6K | Well drained | B | Very limited | Very limited |
| Yunque-Moteado complex, 20 to 60 percent slopes | 3K | Moderately well drained | B/D | Very limited | Very limited |
| Zarzal very cobbly clay, 40 to 90 percent slopes | 3K | Well drained | B | Very limited | Very limited |
| Cristal-Zarzal complex, 5 to 40 percent slopes | 2K | Somewhat poorly drained | B/D | Very limited | Very limited |
| Palm-Yunque complex, 40 to 90 percent slopes, extremelly stony | 2K | Poorly drained | C/D | Very limited | Very limited |
| Yunque-Los Guineos-Moteado complex, 5 to 40 percent slopes | 2K | Moderately well drained | B/D | Very limited | Very limited |
| Humatas-Zarzal complex, 5 to 40 percent slopes | 2K | Well drained | C | Very limited | Very limited |
| Yunque cobbly clay,40 to 90 percent slopes, extremely stony | 2K | Moderately well drained | B/D | Very limited | Very limited |
| Picacho-Utuado complex, 5 to 40 percent slopes | 1K | Poorly drained | B/D | Very limited | Very limited |
| Picacho-Ciales complex, 5 to 40 percent slopes | 1K | Poorly drained | B/D | Very limited | Very limited |
| Picacho-Utuado complex, 40 to 90 percent slopes | 1K | Poorly drained | B/D | Very limited | Very limited |
| Dwarf-El Duque complex, 5 to 60 percent slopes, windswept | 753 | Poorly drained | B/D | Very limited | Very limited |
| Sonadora-Caguabo complex, 40 to 90 percent slopes | 726 | Well drained | D | Very limited | Very limited |
| Sonadora-Caguabo complex, 20 to 40 percent slopes | 310 | Well drained | D | Very limited | Very limited |
| Icacos loam, occasionally flooded | 294 | Poorly drained | B/D | Very limited | Very limited |
| Prieto very cobbly clay loam, 20 to 60 percent slopes | 196 | Poorly drained | C/D | Very limited | Very limited |
| Guayabota-Yunque complex, 20 to 60 percent slopes | 187 | Poorly drained | C/D | Very limited | Very limited |
| Caguabo gravelly clay loam, 12 to 20 percent slopes | 148 | Well drained | D | Very limited | Very limited |
| Luquillo-El Verde complex, 0 to 5 percent slopes, occasionally flooded | 144 | Somewhat poorly drained | C/D | Very limited | Very limited |
| Humatas clay, 40 to 60 percent slopes | 6 | Well drained | C | Very limited | Very limited |
What This Means
Building & Foundations
About 100% 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.