Soil series profile

Sharkey soil series

Sharkey is a poorly drained soil with a clay surface, mapped on 3,645,880 acres in 66 counties across 5 states. Hydrologic group D.

#8 by mapped area very-fine Chromic Epiaquerts (Vertisols)

Drainage class
Poorly drained
>99% of mapped acres
Hydrologic group
D
99% of mapped acres
Typical topsoil pH
6.8
neutral · range 5.3–6.8
Mapped area
3.6M
acres in 66 counties, 5 states

Typical Sharkey profile

Texture and pH by depth

Typical Sharkey soil profile by depth 0 in 20 in 40 in 60 in 0–5 in · Ap · pH 5.3 · 60% clay Clay 5–28 in · Bg · pH 6.3 · 75% clay Clay 28–49 in · Bssg · pH 7.5 · 75% clay Clay 49–80 in · Cssyg · pH 7.5 · 56% clay Clay
Depth to scale. More strongly shaded layers hold more clay. Horizon names are the soil survey's (A = topsoil, B = subsoil, C = parent material).
Show as a table
Typical Sharkey horizons (representative values)
Depth Texture pH Clay Sand Organic matter
0–5 in (Ap) Clay 5.3 60% 2% 2.25%
5–28 in (Bg) Clay 6.3 75% 2% 0.25%
28–49 in (Bssg) Clay 7.5 75% 2% 0.25%
49–80 in (Cssyg) Clay 7.5 56% 6% 0.25%

Representative values from the most extensive Sharkey map unit (Sharkey clay, 0 to 1 percent slopes, rarely flooded, south, survey area LA065). Other map units of this series vary within the series range.

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

What this means

What Sharkey soil means for gardens, lawns and septic systems

For gardens

Typical topsoil in Sharkey soils is neutral: pH 6.8 (most land between 5.3 and 6.8), the range most vegetables, flowers and lawn grasses prefer.

Clayey topsoil covers 93% of mapped Sharkey acres. Clay holds water and nutrients but drains slowly and compacts if worked wet: add compost, avoid tilling soggy soil and consider raised beds. The most common surface texture is clay (76% of mapped Sharkey acres).

>99% of mapped Sharkey acres is somewhat poorly to very poorly drained, so soil stays soggy for long spells after rain and in wet seasons. Raised beds, plants that tolerate wet feet, and not working the soil while wet all help.

For lawns and yards

On 99% of mapped acres, rain soaks in slowly (hydrologic groups C and D, including dual groups that are D until drained). Expect runoff and puddles after heavy rain: core-aerate compacted lawns and keep ground sloping away from foundations.

A seasonal high water table comes within 18 inches of the surface on >99% of mapped acres, often in spring. Basements, sump pumps and lawns in low spots feel it first.

For a septic system

For conventional septic absorption fields, NRCS rates 99% of the acres in mapped Sharkey soils very limited, 0% somewhat limited and 0% not limited (1% not rated, such as urban land, pits or water).

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.

Flooding is mapped on 81% of the acres (18% occasional, 22% frequent).

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 Sharkey soil is found

Mapped acres

Sharkey is mapped in Louisiana, Arkansas, Mississippi, Missouri and Tennessee. The 60 counties with the most Sharkey acres:

Counties with the most mapped Sharkey soil
County Acres Share of county land
Madison Parish, LA 219,441 56.0%
Tensas Parish, LA 182,845 46.9%
Mississippi County, AR 171,502 29.9%
Desha County, AR 159,721 33.5%
Bolivar County, MS 148,617 27.8%
Washington County, MS 140,120 31.8%
Crittenden County, AR 137,196 35.3%
Tunica County, MS 134,197 46.5%
Concordia Parish, LA 128,686 29.6%
Iberville Parish, LA 124,803 31.7%
Sharkey County, MS 115,001 44.7%
East Carroll Parish, LA 109,453 41.3%
New Madrid County, MO 106,661 26.4%
Pemiscot County, MO 106,253 34.6%
St. Landry Parish, LA 102,454 17.4%
Issaquena County, MS 101,461 40.9%
Phillips County, AR 98,611 22.2%
Pointe Coupee Parish, LA 98,291 27.9%
Yazoo County, MS 95,265 17.0%
Avoyelles Parish, LA 91,142 17.2%
Chicot County, AR 90,259 23.2%
Catahoula Parish, LA 85,072 19.1%
Poinsett County, AR 79,340 16.6%
Monroe County, AR 70,660 18.2%
Franklin Parish, LA 60,849 15.6%
Mississippi County, MO 60,826 24.1%
Dunklin County, MO 53,111 16.0%
West Baton Rouge Parish, LA 51,855 42.8%
St. Martin Parish, LA 49,323 10.6%
Stoddard County, MO 47,548 9.5%
Coahoma County, MS 41,509 12.5%
St. Francis County, AR 37,966 9.4%
Lee County, AR 37,254 9.7%
Warren County, MS 30,644 8.4%
Scott County, MO 26,012 10.2%
Wilkinson County, MS 20,390 4.7%
Lauderdale County, TN 18,945 6.3%
Sunflower County, MS 17,489 4.2%
West Carroll Parish, LA 17,112 7.5%
Dyer County, TN 16,404 5.0%
Craighead County, AR 16,218 3.6%
West Feliciana Parish, LA 15,743 6.2%
Quitman County, MS 12,517 5.2%
Adams County, MS 12,278 4.8%
Jefferson County, MS 11,130 3.6%
Lake County, TN 9,694 9.4%
Shelby County, TN 9,573 2.0%
East Baton Rouge Parish, LA 9,299 3.2%
Lawrence County, AR 8,772 2.3%
Carroll County, MS 7,720 2.0%
Cape Girardeau County, MO 7,511 2.1%
Jackson County, AR 5,598 1.4%
Ascension Parish, LA 5,167 2.8%
DeSoto County, MS 5,113 1.7%
Tipton County, TN 5,022 1.7%
Lafayette Parish, LA 4,666 2.7%
LaSalle Parish, LA 4,601 1.1%
Richland Parish, LA 3,607 1.0%
Cross County, AR 2,304 0.6%
Tallahatchie County, MS 1,887 0.5%

Septic absorption fields

NRCS rating, share of Sharkey acres

Not limited 0%
Somewhat limited 0%
Very limited 99%
Not rated 1%
Septic tank absorption field rating across mapped Sharkey acres. Scale 0 to 100% of mapped land.
Show as a table
Septic tank absorption field rating across mapped Sharkey acres.
CategoryShare of acres
Not limited0.0%
Somewhat limited0.0%
Very limited98.9%
Not rated1.1%

Drainage, water table and flooding

Share of Sharkey acres

Depth to seasonal high water table
About 0 inches (median where reported); within 18 inches on >99% of acres.
Flooding
Mapped as flooding on 81% of acres (18% occasional, 22% frequent).
Slope
Typically 0–1% (median 0%).
Topsoil organic matter
Median 2.2%.

Drainage class

Excessively drained 0%
Somewhat excessively drained 0%
Well drained 0%
Moderately well drained 0%
Somewhat poorly drained 0%
Poorly drained >99%
Very poorly drained <1%
Not rated <1%
Drainage class across mapped Sharkey acres. Scale 0 to 100% of mapped land.
Show as a table
Drainage class across mapped Sharkey acres.
CategoryShare of acres
Excessively drained0.0%
Somewhat excessively drained0.0%
Well drained0.0%
Moderately well drained0.0%
Somewhat poorly drained0.0%
Poorly drained99.7%
Very poorly drained0.2%
Not rated0.1%

Hydrologic soil group

A: fast infiltration (mostly sandy or gravelly) 0%
B: moderate infiltration 0%
C: slow infiltration 0%
D: very slow infiltration (clayey, shallow or wet) 99%
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%
Not rated 1%
Hydrologic soil group across mapped Sharkey acres. Scale 0 to 100% of mapped land.
Show as a table
Hydrologic soil group across mapped Sharkey acres.
CategoryShare of acres
A: fast infiltration (mostly sandy or gravelly)0.0%
B: moderate infiltration0.0%
C: slow infiltration0.0%
D: very slow infiltration (clayey, shallow or wet)98.9%
A/D: D as is, A if drained0.0%
B/D: D as is, B if drained0.0%
C/D: D as is, C if drained0.0%
Not rated1.1%

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 Sharkey (component kind "Series") in SSURGO: 3,645,880 acres.
Method
Shares are by mapped acres of Sharkey components. The profile comes from the single largest Sharkey component. Full methodology.

Independent reference site. No government affiliation or endorsement.

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