Major Soils of the Intermediate Soils and Their Classification

Abstract

The Intermediate zone covers about 1.3 million ha and lies between the Wet and Dry climatic zones. Thirty-six soil series have been identified and mapped as 52 mapping units of soil associations or complexes. As the Intermediate zone is the area where the Wet zone gradually changes to Dry zone some of the soil series found in both these two zones also could be found. The Intermediate zone is categorized to three elevation zones as the low country, mid-country and up country Intermediate zone. The soils of the low country Intermediate zone are further divided to physiographic divisions of depositional surfaces and erosional/residual planation surfaces. The soils of the mid-country Intermediate zone is discussed according to physiographic groups of erosional/residual planation surfaces of rolling, hill and valley landforms, ridge and valley landforms of low to moderate relief and moderate to high relief, and depositional surfaces. Mountain landform, ridge and valley landform, hill ridge, and valley landform are the physiographic groupings of the up country Intermediate zone. A benchmark soil series belonging to each of these landforms are discussed with the color photos of the landscape and soil profiles.