Soil series profile

Sulco soil series

Sulco is a well drained soil with a silt loam surface, mapped on 587,170 acres in 16 counties across 2 states. Hydrologic group B.

#446 by mapped area coarse-silty Aridic Haplustepts (Inceptisols)

Drainage class: Well drained
Hydrologic group: B
Typical topsoil pH: 7.9
Mapped area: 587k

Typical Sulco profile

Texture and pH by depth

Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).

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Typical Sulco horizons (representative values)
Depth	Texture	pH	Clay	Sand	Organic matter
0–6 in (A)	Silt loam	7.9	11%	21%	1.25%
6–79 in (Bk)	Silt loam	8.2	13%	14%	0.75%

Representative values from the most extensive Sulco map unit (Sulco silt loam, 9 to 30 percent slopes, survey area NE087). Other map units of this series vary within the series range.

Stock photo for illustration, not a sample of this soil series. Credit on the Sources & method page.

What this means

What Sulco soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Sulco soils is moderately alkaline: pH 7.9 (most land between 7.6 and 7.9). Acid-loving plants such as blueberries and azaleas struggle without amended beds, and some trees and shrubs show iron chlorosis (yellow leaves with green veins).

Loamy topsoil (loam, silt loam and similar) covers 100% of mapped Sulco acres: generally the easiest soil to garden, holding moisture without staying waterlogged. The most common surface texture is silt loam (66% of mapped Sulco acres).

100% of mapped Sulco acres is moderately well to excessively drained, which suits most garden plants.

For lawns and yards

Most land is in hydrologic groups B and C, where rain soaks in at a moderate pace.

For a septic system

For conventional septic absorption fields, NRCS rates 90% of the acres in mapped Sulco soils very limited, 10% somewhat limited and 0% not limited.

Where the soil is very limited (slow permeability, a high water table, flooding, shallow bedrock or steep slopes), alternative systems such as mound or sand-filter designs are common and cost more.

Only a licensed site evaluation or perc test at the actual lot decides whether a system is allowed and which design.

Generated from the mapped numbers above using fixed rules, not a site visit. See how these notes are written.

Where Sulco soil is found

Mapped acres

Sulco is mapped in Nebraska and Kansas.

Counties with the most mapped Sulco soil
County	Acres	Share of county land
Hitchcock County, NE	167,372	36.9%
Hayes County, NE	142,536	31.2%
Dundy County, NE	73,477	12.5%
Chase County, NE	53,155	9.3%
Keith County, NE	49,440	7.3%
Red Willow County, NE	20,888	4.6%
Cheyenne County, KS	19,282	3.0%
Frontier County, NE	16,828	2.7%
Garden County, NE	14,045	1.3%
Perkins County, NE	12,627	2.2%
Deuel County, NE	6,153	2.2%
Rawlins County, KS	3,414	0.5%
Scotts Bluff County, NE	2,779	0.6%
Dawes County, NE	2,562	0.3%
Lincoln County, NE	2,546	0.2%
Cheyenne County, NE	67	0.0%

Septic absorption fields

NRCS rating, share of Sulco acres

Not limited 0%

Somewhat limited 10%

Very limited 90%

Septic tank absorption field rating across mapped Sulco acres. Scale 0 to 100% of mapped land.

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Septic tank absorption field rating across mapped Sulco acres.
Category	Share of acres
Not limited	0.0%
Somewhat limited	9.6%
Very limited	90.4%

Drainage, water table and flooding

Share of Sulco acres

Depth to seasonal high water table: None reported within about 6.5 feet (median where reported).
Flooding: Not mapped as flooding on most acres.
Slope: Typically 20–45% (median 20%).
Topsoil organic matter: Median 1.2%.

Drainage class

Excessively drained 0%

Somewhat excessively drained 0%

Well drained 100%

Moderately well drained 0%

Somewhat poorly drained 0%

Poorly drained 0%

Very poorly drained 0%

Drainage class across mapped Sulco acres. Scale 0 to 100% of mapped land.

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Drainage class across mapped Sulco acres.
Category	Share of acres
Excessively drained	0.0%
Somewhat excessively drained	0.0%
Well drained	100.0%
Moderately well drained	0.0%
Somewhat poorly drained	0.0%
Poorly drained	0.0%
Very poorly drained	0.0%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%

B: moderate infiltration 100%

C: slow infiltration 0%

D: very slow infiltration (clayey, shallow or wet) 0%

A/D: D as is, A if drained 0%

B/D: D as is, B if drained 0%

C/D: D as is, C if drained 0%

Hydrologic soil group across mapped Sulco acres. Scale 0 to 100% of mapped land.

Show as a table

Hydrologic soil group across mapped Sulco acres.
Category	Share of acres
A: fast infiltration (mostly sandy or gravelly)	0.0%
B: moderate infiltration	100.0%
C: slow infiltration	0.0%
D: very slow infiltration (clayey, shallow or wet)	0.0%
A/D: D as is, A if drained	0.0%
B/D: D as is, B if drained	0.0%
C/D: D as is, C if drained	0.0%

Sources & data dates

Source: USDA NRCS Soil Survey Geographic Database (SSURGO), queried through Soil Data Access. Public domain.
Data date: SSURGO as published on November 3, 2026 (most recent survey area update October 26, 2026). NRCS refreshes SSURGO each October.
Scope: All map unit components named Sulco (component kind "Series") in SSURGO: 587,170 acres.
Method: Shares are by mapped acres of Sulco components. The profile comes from the single largest Sulco component. Full methodology.

Independent reference site. No government affiliation or endorsement.

Full narrative description: USDA Official Soil Series Description for Sulco.