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Crawford County Soil Data

Crawford County, Iowa

USDA SSURGO / PHZM

Avg pH

6.4

Texture

Silt Loam

Drainage

N/A

Organic Matter

2.8%

Hydrologic Group

N/A

Data Story

About Soil in Crawford County, Iowa

Neutral Soils and High Scores

Crawford's soil carries a pH of 6.41, sitting right at the state average and very close to the 6.5 national median. The county boasts a high soil score of 80.1, indicating excellent overall quality.

Dense, Silt-Heavy Ground

The soil is remarkably high in silt at 63.8%, with only 10.2% sand. This silt-heavy mix creates a dense environment that is exceptionally good at holding onto moisture and nutrients.

Leading in Water Capacity

Though organic matter is 2.83%, the available water capacity is a chart-topping 0.217 in/in. This means the soil acts like a sponge, storing significantly more water for plants than the average Iowa soil.

Resilient During Dry Spells

Specific drainage and hydrologic group data are not available for this county. However, the high silt and clay content suggest that water moves slowly, which acts as a major advantage during dry periods.

Powerful Production in Zone 5a

Zone 5a gardeners will find this moisture-retentive soil perfect for heavy feeders like corn or sunflowers. With a bit of mulch to manage the surface, this soil is a true powerhouse for production.

Soil Composition

Silt Loam
Sand: 10.2%
Silt: 63.8%
Clay: 26.0%
Silt Loam

Soil pH

6.4pH
6.41201097309058
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

Hydrologic group data not available.

Drainage Class

Drainage class data not available.

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

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Frequently Asked Questions

What type of soil does Crawford County have?

Crawford County's soil is classified as Silt Loam. This indicates the relative proportions of sand, silt, and clay — 10% sand, 64% silt, and 26% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Crawford County's soil acidic or alkaline?

Crawford County's soil has a pH of 6.4, which is moderately acidic. This range suits many crops and is common across much of the eastern US.

What is the drainage class for Crawford County?

Drainage class data is not currently available for Crawford County.

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

Based on Crawford County's Silt Loam texture, pH of 6.4, and drainage class, the soil is well suited for vegetables, grains, and most field crops, row crops and vegetable gardens.

What USDA soil order is found in Crawford County?

The dominant USDA soil order for Crawford County is not currently available in our dataset.

Soil & Planting Advisory: Crawford County

Soil Verdict

Crawford 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

Crawford County closely matches the Iowa average hardiness conditions. The zone range of 5a-5b within the county means soil and planting decisions should account for local elevation and topography.

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.