Union Parish Soil Data

Union Parish, Louisiana

Avg pH

5.1

Texture

Silt loam

Drainage

Poorly drained

Organic Matter

1.7%

Hydrologic Group

D

Data Story

About Soil in Union Parish, Louisiana

The Weathered Alfisols of Union

Union Parish soils are acidic with a pH of 5.15, falling below the state average of 5.74. These are classified as Alfisols, which are older, more weathered soils typical of North Louisiana's uplands.

Silt Loam with High Sand Content

The soil is a silt loam with 49.8% sand, 34.6% silt, and 15.6% clay. This high sand percentage makes it easier to till than the heavy clays found in the southern parishes.

Challenges in Organic Retention

Organic matter is low at 1.68%, trailing both state and national averages. The available water capacity of 0.151 in/in is also below the state benchmark, meaning these soils can dry out quickly.

Poorly Drained Group D Soils

Despite the sand content, these soils are classified as poorly drained and belong to hydrologic group D. This indicates a high runoff potential and a layer that restricts water from moving downward easily.

Acid-Loving Plants for Zone 8b

Zone 8b is perfect for camellias and gardenias that love the natural acidity here. Although the soil score is 24.4, your garden will thrive if you supplement it with organic mulch and consistent watering.

Soil Composition

Silt loam
Sand: 49.8%
Silt: 34.6%
Clay: 15.6%
Silt loam

Soil pH

5.1pH
5.14807919421828
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

Poorly drained

Water is removed so slowly that the soil is wet at or near the surface much of the year. Drainage improvement usually needed.

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.

Frequently Asked Questions

What type of soil does Union Parish have?

Union Parish's soil is classified as Silt loam. This indicates the relative proportions of sand, silt, and clay — 50% sand, 35% silt, and 16% clay. Loamy soils hold moisture well and support a wide range of plants.

Is Union Parish's soil acidic or alkaline?

Union Parish's soil has a low pH of 5.1, which is strongly acidic. Acidic soils benefit from lime applications to raise pH and improve nutrient availability.

What is the drainage class for Union Parish?

Union Parish has a dominant drainage class of "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 Union Parish's soil?

Based on Union Parish's Silt loam texture, pH of 5.1, and Poorly drained, the soil is well suited for acid-loving plants like blueberries and azaleas, row crops and vegetable gardens, rice, cranberries, and other water-tolerant species.

What USDA soil order is found in Union Parish?

Union Parish's dominant soil order is Alfisols. Alfisols are moderate to high base-status soils with a clay-enriched subsoil. They support productive forests and cropland across temperate regions.

Other Counties in Louisiana

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.