Mean annual air temperature ranges from 55 to 58 degrees F, and the mean annual precipitation ranges from 40 to 45 inches. These are the Frenchmill , Killarney , Knobtop and Loughboro soils. Frenchmill soils are very deep and are below Irondale soils in the landscape. Killarney soils are on lower slopes and have a fragipan. Knobtop soils occupy the gentle to sloping mountain ridges and tops and contain less than 15 percent coarse fragments.
Loughboro soils are on nearly level areas at the base of the mountains.
They are deep, poorly drained soils and contain only a trace of coarse fragments. Runoff is high. Permeability is moderate. Water saturates the horizon just above the bedrock for short periods during late winter or early spring. Nearly all these soils remain in mixed hardwood forest with a few shortleaf pine in some places.