Monona County Soil Data
Monona County, Iowa
Avg pH
6.8
Texture
Silt loam
Drainage
Moderately well drained
Organic Matter
2.5%
Hydrologic Group
C
Data Story
About Soil in Monona County, Iowa
Silt Loam and Young Entisols
Monona County is dominated by silt loam textures and the Entisols taxonomic order, representing relatively young soil development. The average pH of 6.77 is slightly alkaline, sitting above the national median of 6.5. This pH level is favorable for many crops that prefer less acidic conditions.
Silt-Heavy Soils with Moderate Workability
The soil profile consists of 54.7% silt, 27.2% clay, and 13.1% sand. While the high silt content provides a smooth texture and good nutrient storage, the 27.2% clay can lead to crusting if the soil surface dries too quickly. Maintaining surface cover is essential to keep this soil workable.
Lower Organic Matter but Stable Potential
Organic matter levels average 2.48%, which is notably lower than the state average of 3.81%. Available water capacity matches Mitchell County at 0.184 in/in, falling just short of the 0.195 in/in state benchmark. Gardeners should consider adding compost to boost fertility and moisture retention.
Managing Runoff in Group C Soils
The county's soils are moderately well drained but fall into hydrologic group C. This means while the soil drains reasonably well, it has a slower infiltration rate that can lead to runoff during heavy rains. Proper land management is key to preventing erosion in this silt-rich landscape.
Gardening in the Zone 5a Climate
Monona County's Zone 5a climate supports robust harvests of corn, soybeans, and hardy perennials. The silt loam is particularly well-suited for alfalfa and deep-rooted prairie plants that can handle the variable Iowa weather. It is a great environment for establishing a productive backyard garden.
Soil Composition
Soil pH
Soil Series
Detailed soil series data not yet available for this county.
Hydrologic Group
Group C — Moderate-High Runoff
Soils with slow infiltration rates, often with a layer that impedes downward water movement. Higher clay content restricts drainage.
Drainage Class
Moderately well drained
Water is removed somewhat slowly. May have a slowly permeable layer or seasonal water table.
Soil Profile
Dominant texture: Silt loam
Typical soil profile. Actual depths vary by location.
USDA Soil Orders
Frequently Asked Questions
What type of soil does Monona County have?
Monona County's soil is classified as Silt loam. This indicates the relative proportions of sand, silt, and clay — 13% sand, 55% silt, and 27% clay. Loamy soils hold moisture well and support a wide range of plants.
Is Monona County's soil acidic or alkaline?
Monona County's soil has a pH of 6.8, which is near neutral. This range is ideal for most garden plants and field crops.
What is the drainage class for Monona County?
Monona County has a dominant drainage class of "Moderately well drained." Well-drained soils allow excess water to move through quickly, reducing waterlogging risk and supporting most field and garden crops.
What crops or plants grow well in Monona County's soil?
Based on Monona County's Silt loam texture, pH of 6.8, and Moderately well drained, the soil is well suited for vegetables, grains, and most field crops, row crops and vegetable gardens, most annual and perennial crops.
What USDA soil order is found in Monona County?
Monona County's dominant soil order is Entisols. Entisols are recently formed soils with little to no horizon development. They are common on floodplains, steep slopes, and sandy deposits.
Planning your lawn? View lawn care data for Monona County on LawnByCounty.com →
Other Counties in Iowa
Soil data sourced from USDA SSURGO via Soil Data Access. Data is informational only and should not be used as a substitute for on-site soil testing. Contact your local NRCS office for site-specific soil information.