Typically, St. Albans soils have a very dark grayish brown slaty loam Ap horizon, dark yellowish brown or brown slaty fine sandy loam and coarse sandy loam B horizons, and friable dark brown to very dark grayish brown slaty coarse sandy loam C horizons. Thickness of the solum ranges from 15 to 30 inches. Depth to fragmental or clayey layers or to bedrock is more than 60 inches. They are comprised mainly of slate and shale. Mean annual soil temperature at a depth of 20 inches ranges from 47 to 52 degrees Fahrenheit.
Reaction ranges from very strongly acid to medium acid.
The A and Ap horizons have hue of 10YR or 2.5Y, value of 3 or 4, and chroma of 2 and 3. A discontinued E horizon is present in some pedons. They are sandy loam, fine sandy loam, and loam, and their slaty analogues. Structure is weak to strong, fine or medium granular. Consistence is friable or very friable.