Union Parish, Louisiana
The most common soil here is Darley, on about 15% of the land: a fine sand, loose sand that holds almost no water. Ruston and Sacul come next.
About 44% of the land drains well, and 20% stays wet for long stretches; groundwater comes within two feet of the surface under 26% of it.
USDA rates 95% of the land very limited for a standard septic drain field, and 47% very limited for homes with basements. That means extra cost or special design, not that it can't be done.
Worth knowing: 24% of the land floods occasionally or more.
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 Union Parish, Louisiana, 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 Union Parish, Louisiana. 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 |
|---|---|---|---|---|---|
| Ruston fine sandy loam, 1 to 5 percent slopes | 62K | Well drained | B | Not limited | Very limited |
| Darley gravelly fine sandy loam, 5 to 12 percent slopes | 55K | Well drained | C | Not limited | Very limited |
| Iuka-Dela complex, 0 to 1 percent slopes, frequently flooded | 40K | Moderately well drained | C | Very limited | Very limited |
| Guyton silt loam, 0 to 1 percent slopes, frequently flooded | 36K | Poorly drained | C/D | Very limited | Very limited |
| Darley gravelly fine sandy loam, 12 to 30 percent slopes | 33K | Well drained | C | Very limited | Very limited |
| Sacul very fine sandy loam, 5 to 12 percent slopes | 30K | Moderately well drained | C | Somewhat limited | Very limited |
| Smithdale fine sandy loam, 8 to 15 percent slopes | 22K | Well drained | B | Somewhat limited | Very limited |
| Kirvin fine sandy loam, 5 to 12 percent slopes | 22K | Well drained | C | Somewhat limited | Very limited |
| Malbis fine sandy loam, 1 to 5 percent slopes | 22K | Moderately well drained | C | Somewhat limited | Very limited |
| Sacul very fine sandy loam, 1 to 5 percent slopes | 19K | Moderately well drained | D | Very limited | Very limited |
| Water | 19K | D | Not rated | Not rated | |
| Litro clay, frequently flooded | 17K | Poorly drained | D | Very limited | Very limited |
| Kirvin fine sandy loam, 1 to 5 percent slopes | 17K | Well drained | C | Somewhat limited | Very limited |
| Libuse silt loam, 1 to 5 percent slopes | 16K | Moderately well drained | D | Very limited | Very limited |
| Savannah fine sandy loam, 1 to 5 percent slopes | 13K | Moderately well drained | C/D | Very limited | Very limited |
| Mahan fine sandy loam, 1 to 5 percent slopes | 12K | Well drained | B | Not limited | Very limited |
| Frizzell silt loam, 0 to 2 percent slopes | 12K | Somewhat poorly drained | C | Somewhat limited | Very limited |
| Sawyer silt loam, 1 to 5 percent slopes | 11K | Moderately well drained | C/D | Very limited | Very limited |
| Groom silty clay loam, frequently flooded | 11K | Poorly drained | C/D | Very limited | Very limited |
| Groom silt loam, occasionally flooded | 10K | Poorly drained | C/D | 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 47% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.
Septic Systems
About 95% 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
Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.