Soil survey area

Medina County, Texas

Survey Area TX325• Texas
The short version

The most common soil here is Eckrant, on about 8% of the land: a very cobbly clay, sticky when wet and rock-hard when dry. Knippa and Castroville come next.

About 80% of the land drains well, and 4% stays wet for long stretches.

USDA rates 84% of the land very limited for a standard septic drain field, and 62% very limited for homes with basements. That means extra cost or special design, not that it can't be done.

Worth knowing: 6% of the land floods occasionally or more, and bedrock lies within 40 inches under 30% 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 ground underfoot

The soils you're most likely standing on

The biggest named soils in Medina County, Texas, each drawn five feet deep from its official USDA description, in its recorded colors.

Eckrant
8% of the area
Very cobbly clay topsoil · well drained
Sticky when wet and rock-hard when dry. Drains slowly.
Mollisols
Knippa
6% of the area
Clay topsoil · well drained
Sticky when wet and rock-hard when dry. Drains slowly.
Mollisols
Castroville
5% of the area
Silty clay loam topsoil · well drained
Smooth and slightly sticky. Holds a lot of water.
Mollisols
Montell
4% of the area
Clay topsoil · moderately well drained
Sticky when wet and rock-hard when dry. Drains slowly.
Vertisols
Olmos
4% of the area
Very gravelly loam topsoil · well drained
A balanced mix that crumbles in your hand. The gardener's ideal.
Mollisols
Divot
4% of the area
Clay loam topsoil · well drained
Firm and a little sticky. Holds water and nutrients well.
Mollisols

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 D (very slow infiltration, high 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 Medina County, Texas. Search your address to find the exact soil composition, drainage, and series details at your specific location.

Soil Map UnitAcresDrainageHydro GroupDwellingsSeptic
Eckrant-Rock outcrop association, 1 to 10 percent slopes 53K Well drainedDVery limitedVery limited
Eckrant-Rock outcrop association, 8 to 30 percent slopes 50K Well drainedDVery limitedVery limited
Knippa clay, 0 to 1 percent slopes 48K Well drainedCSomewhat limitedVery limited
Speck association, 1 to 8 percent slopes 43K Well drainedDVery limitedVery limited
Olmos very cobbly loam, 1 to 8 percent slopes, rubbly 35K Well drainedDVery limitedVery limited
Montell clay, 0 to 1 percent slopes 34K Moderately well drainedDVery limitedVery limited
Castroville clay loam, 0 to 1 percent slopes 33K Well drainedBSomewhat limitedSomewhat limited
Yologo gravelly loam, 1 to 8 percent slopes 30K Well drainedDVery limitedVery limited
Victoria clay, 0 to 1 percent slopes 29K Somewhat poorly drainedDVery limitedVery limited
Real association, undulating 29K Well drainedDVery limitedVery limited
Divot clay loam, occasionally flooded 28K Well drainedCVery limitedVery limited
Monteola gravelly clay, 1 to 5 percent slopes 22K Moderately well drainedDVery limitedVery limited
Duval very fine sandy loam, 1 to 3 percent slopes 20K Well drainedBNot limitedSomewhat limited
Nusil soils, 0 to 5 percent slopes 18K Moderately well drainedCNot limitedVery limited
Pratley clay, 0 to 3 percent slopes 18K Well drainedCVery limitedVery limited
Eckrant-rock outcrop-kerrville association, steep 17K DVery limitedVery limited
Quihi association, gently undulating 16K Well drainedCSomewhat limitedVery limited
Atco loam, 0 to 1 percent slopes 16K Well drainedBNot limitedSomewhat limited
Monteola clay, 1 to 5 percent slopes 15K Moderately well drainedDVery limitedVery limited
Castroville clay loam, 1 to 3 percent slopes 15K Well drainedBSomewhat limitedSomewhat 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.

Mollisols
Fertile grassland soils with thick, dark topsoil. Among the best for agriculture, building, and gardening.
Alfisols
Moderately weathered forest soils with clay-enriched subsoil. Productive for agriculture, generally good for building and septic.
Inceptisols
Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.
Vertisols
High-clay soils that shrink and swell dramatically. Fertile but challenging for foundations and septic systems.

What This Means

Building & Foundations

About 62% 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 84% 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.

Look Up a Specific Address

📍