Soil Types in Madison County, Alabama
- Madison County features many distinct soil types.Arid soil image by Igor Baryshev from Fotolia.com
Madison County, Alabama, is situated in the Tennessee Valley, just south of the Tennessee border and 100 miles south of Nashville. It is Alabama's third most populated county, and its largest town is Huntsville. The county covers 806 square miles. Its soil composition varies tremendously and includes more than 50 distinct soil types, primarily with silt loam textures. A few types, however, comprise the majority of Madison County's total soil composition. - One of the predominant soil types in Madison County is Decatur and Cumberland silty clay loam. A silty clay loam has a varied texture with high levels of organic matter, indicative of loam, combined with the relatively small particle size of silt and clay. Generally, this soil type is found in moderate climates with average annual temperatures of 57 to 61 F and an average annual rainfall of 46 to 54 inches. The soil derives from weathered limestone. It is well-drained, suiting it well to agricultural use, and has a moderate water capacity. The silty clay loam texture extends downward less than 1 foot; from depths of 9 to 13 inches, it becomes silty clay; from 13 to 60 inches, it changes to pure clay.
- Another primary soil type in Madison County is Dickson silt loam. It occurs in similar climates as Decatur and Cumberland soil and also derives from weathered limestone; it combines with a higher concentration of silt. Dickson is moderately well-drained and has a low water capacity. It features relatively little stratification at its uppermost levels, maintaining a silt loam texture down to depths of about 44 inches. From 44 to 60 inches, it becomes gravelly clay.
- Abernathy silt loam is another of Madison County's many silt loam soils. Unlike Dickson or Decatur and Cumberland soils, Abernathy is derived from sedimentary rock and silty alluvium, the deposits from rivers. It is well-drained, has a high ability to transmit water, a high water capacity and a tendency to pond, suiting it to general agricultural usage. The silt loam texture only extends down about 8 inches. From depths of 8 to 80 inches, it becomes silty clam loam.
- Like most of Madison County's soil types, Baxter cherty silt loam has a silty, loamy texture and is found predominantly in moderate climates. It is derived from cherty limestone, which is limestone flecked with high concentrations of quartz and amorphous silica. This soil is well-drained and has a moderate water capacity. Unlike other local silt loams, it is highly gravelly at all depths.
