Arkansas Soil Types

Five major types of soil--alluvial, loess, loam, shale and limestone--make up the majority of the land in the state of Arkansas. Each soil varies in terms of composition and fertility based on its location in the state.

The Arkansas Delta is the eastern part of the state that runs along the Mississippi River. The soil found in this area is a loose, mineral-rich soil that may even contain traces of valuable materials such as gold and others gems. Created by river erosion, this soil is extremely rich and fertile.

Crowley's Ridge is a small rolling hill that rises above the flat, alluvial plains of the Delta. The soil found here, called loess, is an accumulation of wind-blown silt and bits of clay. It is quick to erode when introduced to water or wind, and is also very fertile soil.

The West Gulf Coastal Plain in Arkansas is around the southeastern part of the state, near Louisiana. Characterized by farms and lush forests, the soil found here is sandy loam. Loam, composed of sand, silt and clay, is moist and fertile. As it is easier to till than some soils, farmers often choose to farm on this land.

The Ouachita Mountains run from Oklahoma through central Arkansas, with the Ouachita River running through. The soil found here includes shale and sandstone, which are sedimentary soils that contain mostly clay and tiny particles of crystals such as quartz. As opposed to looser soils, shale is typically found in gray, rock-like sheets with layers that easily break off.

The Ozark Mountains run along the northern part of Arkansas. The soil found here is residual limestone, which is a sedimentary rock made up of silt, sand, clay and often traces of marine organisms' skeletal structures, such as coral. Limestone can erode over time.