Soil Properties

Soil Properties

There are some chemical properties you can determine on your own in identifying a soil type along the upper Gulf Coast:

Soil Color

What color is your soil? Soil color reflects the amount of organic material, conditions of drainage, and the level of oxidation and soil weathering.

Light-colored soil means low organic matter. Darker colors indicate higher organic content. Also, light or pale colors of soil could mean courser soil and heavy leaching.

Dark colors can also mean high water tables and poor drainage (for instance, the gumbo soil along the coast) or the parent material’s color. Red and yellow shades can mean finely textured soil, but red dirt in Alabama and Florida can also mean oxidized iron in the ground. Red and brown subsoil show that there is free movement of air and water through the soil.

Texture

How coarse or how fine the mineral particles in the soil determine texture.

Sandy soils are generally coarser, while silt is fine, smooth, and feels floury. The finest soil particles make up clay, while loam has mixtures of clay, sand and silt, and humus. There are different types of topsoil, each with its own characteristics: sandy loam (feels sandy and rough but has some silt in it; silt loam (feels smooth – like flour, when rubbed between your thumb and fingers); silty clay loam (feels smooth when dry – sticky and slick when wet but has noticeable amounts of silt in it; and clay loam (smooth when dry and sticky and slick when wet – there may be some amounts of silt and sand in it, but there is noticeably more clay).

While there are no hard and fast rules about soil types, these are general rules of thumb when determining your type of soil.

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