soilbycounty

Worth County Soil Data

Worth County, Iowa

USDA SSURGO / PHZM

Avg pH

6.5

Texture

Silt loam

Drainage

Somewhat poorly drained

Organic Matter

6.0%

Hydrologic Group

D

Data Story

About Soil in Worth County, Iowa

Classic Iowa Mollisols

Worth County sits on rich Mollisols with a nearly perfect pH of 6.45, mirroring both the state average and the national median. These 'prairie soils' represent some of the most productive agricultural land in the world.

Balanced Silt Loam Texture

The dominant silt loam texture consists of 38.9% silt and 36.5% sand, creating a workable and versatile medium. This balance, rounded out by 21.1% clay, provides enough structure to hold nutrients without becoming overly heavy.

Exceptional Organic Fertility

With a massive 5.98% organic matter content, Worth County far outpaces the state average of 3.81%. Its available water capacity hits the state benchmark of 0.195 in/in, creating an ideal environment for high-yield growth.

Managing Poorly Drained Soils

Classified as somewhat poorly drained in hydrologic group D, these soils may retain water during wet Iowa springs. This classification suggests that growers should prioritize drainage tiles or raised beds to manage moisture effectively.

High-Yield Potential in Zone 5a

Located in Hardiness Zone 5a, this fertile ground is perfect for sweet corn, soybeans, and hardy perennials. The exceptional organic matter levels provide a natural boost, making this an ideal spot to launch a productive home garden.

Soil Composition

Silt loam
Sand: 36.5%
Silt: 38.9%
Clay: 21.1%
Silt loam

Soil pH

6.5pH
6.45318215721392
Strongly AcidicSlightly AcidicNeutralSlightly AlkalineStrongly Alkaline
Ideal lawn range: 6.0 - 7.0

Soil Series

Detailed soil series data not yet available for this county.

Hydrologic Group

Group D — High Runoff

Clay soils with very slow infiltration rates. Highest runoff potential. These soils have a permanent high water table or are shallow over impervious material.

Runoff potential:High

Drainage Class

Somewhat poorly drained

Water is removed slowly enough that the soil is wet at shallow depths for significant periods. Mottling present.

Soil Profile

Dominant texture: Silt loam

O HorizonOrganic layer
0-2"
A HorizonTopsoil
2-10"
B HorizonSubsoil
10-30"
C HorizonParent material
30-60"
R HorizonBedrock
60"+

Typical soil profile. Actual depths vary by location.

Soil Amendment Products

Browse products to improve your soil health and lawn performance.

Browse Soil Amendments

Frequently Asked Questions

What type of soil does Worth County have?

Worth County's soil is classified as Silt loam. This indicates the relative proportions of sand, silt, and clay — 37% sand, 39% silt, and 21% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Worth County's soil acidic or alkaline?

Worth County's soil has a pH of 6.5, which is moderately acidic. This range suits many crops and is common across much of the eastern US.

What is the drainage class for Worth County?

Worth County has a dominant drainage class of "Somewhat poorly drained." Poorly drained soils retain water for extended periods, which can limit crop choices and may require tile drainage or raised beds.

What crops or plants grow well in Worth County's soil?

Based on Worth County's Silt loam texture, pH of 6.5, and Somewhat poorly drained, the soil is well suited for vegetables, grains, and most field crops, row crops and vegetable gardens, rice, cranberries, and other water-tolerant species.

What USDA soil order is found in Worth County?

Worth County's dominant soil order is Mollisols. Mollisols are fertile, dark-colored soils that formed under grassland vegetation. They are among the most productive agricultural soils in the world.

Soil & Planting Advisory: Worth County

Soil Verdict

Worth County is in USDA hardiness zone 5a, a cold climate zone. where winter lows can reach -20°F. Freeze-thaw cycles are moderate; soil biology slows in winter but recovers reliably in spring, supporting a broad range of plants.

Planting Guidance

A wide plant palette is possible: deciduous trees, most shrubs, cool-season vegetables, and many perennials thrive here. With extreme winter lows, any marginally hardy plants need heavy mulch and wind protection. Always match plant selections to the specific microclimate of your property — low spots, slopes, and wind exposure can shift effective hardiness by half a zone.

Soil Implications

Moderate freeze-thaw cycles naturally aerate the soil but can also cause compaction in clay-heavy areas; annual core aeration is beneficial. Organic matter amendments decompose at a moderate pace — aim for 3-5% organic content for optimal fertility. When soil temperatures drop below freezing, microbial nitrogen cycling stops; spring fertilization is more effective than late-fall application.

Regional Context

Worth County closely matches the Iowa average hardiness conditions.

Other Counties in Iowa

By Evan Brooks, Data EditorUpdated Reviewed by Evan Brooks, Data Editor

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.