Soil survey area

Whiteside County, Illinois

Survey Area IL195• Illinois
The short version

The most common soil here is Seaton, on about 8% of the land: a silt loam, smooth, like flour. Dickinson and Richwood come next.

About 59% of the land drains well, and 37% stays wet for long stretches; groundwater comes within two feet of the surface under 38% of it.

USDA rates 72% of the land very limited for a standard septic drain field, and 49% very limited for homes with basements. That means extra cost or special design, not that it can't be done.

Worth knowing: 11% 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 ground underfoot

The soils you're most likely standing on

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

Seaton
8% of the area
Silt loam topsoil · well drained
Smooth, like flour. Fertile and holds water well.
Alfisols
Dickinson
6% of the area
Fine sandy loam topsoil · well drained
Gritty and crumbly. Drains fast and warms early in spring.
Mollisols
Richwood
4% of the area
Silt loam topsoil · well drained
Smooth, like flour. Fertile and holds water well.
Mollisols
Greenbush
4% of the area
Silt loam topsoil · well drained
Smooth, like flour. Fertile and holds water well.
Alfisols
Ambraw
4% of the area
Clay loam topsoil · poorly drained
Firm and a little sticky. Holds water and nutrients well.
Mollisols
Marshan
4% of the area
Silty clay loam topsoil · poorly drained
Smooth and slightly sticky. Holds a lot of water.
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 B (moderate infiltration). 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 Whiteside County, Illinois. Search your address to find the exact soil composition, drainage, and series details at your specific location.

Soil Map UnitAcresDrainageHydro GroupDwellingsSeptic
Dickinson sandy loam, 0 to 2 percent slopes 20K Well drainedANot limitedVery limited
Marshan loam, sandy subsratum, 0 to 2 percent slopes 17K Poorly drainedB/DVery limitedVery limited
Richwood silt loam, 2 to 5 percent slopes 17K Well drainedBSomewhat limitedVery limited
Greenbush silt loam, 2 to 5 percent slopes 13K Well drainedBSomewhat limitedSomewhat limited
Drummer silty clay loam, 0 to 2 percent slopes 13K Poorly drainedB/DVery limitedVery limited
Seaton-Timula silt loams, 10 to 18 percent slopes, severely eroded 12K Well drainedBSomewhat limitedSomewhat limited
Seaton silt loam, 5 to 10 percent slopes, eroded 11K Well drainedBNot limitedSomewhat limited
Seaton-Timula silt loams, 18 to 35 percent slopes, eroded 10K Well drainedBVery limitedVery limited
Water 10K Not ratedNot rated
Osco silt loam, 2 to 5 percent slopes 9K Well drainedBSomewhat limitedSomewhat limited
Zumbro sandy loam, 1 to 4 percent slopes, rarely flooded 9K Well drainedAVery limitedVery limited
Elburn silt loam, 0 to 2 percent slopes 9K Somewhat poorly drainedB/DVery limitedVery limited
Ambraw loam, 0 to 2 percent slopes, occasionally flooded 9K Poorly drainedC/DVery limitedVery limited
Prophetstown silt loam, 0 to 2 percent slopes 9K Poorly drainedB/DVery limitedVery limited
Port Byron silt loam, 2 to 5 percent slopes 8K Well drainedBNot limitedSomewhat limited
Lawler loam, 0 to 2 percent slopes 8K Somewhat poorly drainedB/DVery limitedVery limited
Fayette silt loam, glaciated, 5 to 10 percent slopes, eroded 8K Well drainedBSomewhat limitedSomewhat limited
Seaton silt loam, 10 to 18 percent slopes, eroded 8K Well drainedBSomewhat limitedSomewhat limited
Orion silt loam, 0 to 2 percent slopes, frequently flooded 8K Somewhat poorly drainedB/DVery limitedVery limited
Ambraw clay loam, 0 to 2 percent slopes, rarely flooded 8K Poorly drainedC/DVery limitedVery 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.

What This Means

Building & Foundations

About 49% of soils have significant building limitations, while the rest are generally suitable. Check specific sites carefully — conditions vary across the area.

Septic Systems

About 72% 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.

Look Up a Specific Address

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