Reaction is very strongly acid or strongly acid. It is commonly silty clay loam but may be silt loam in the lower part in some pedons. Clay content ranges from 24 to 35 percent. Reaction ranges from very strongly acid to moderately acid. It is silt loam with clay content of 20 to 27 percent.
Reaction ranges from very strongly acid to neutral.
No other series is in this family. The Stoy soils are on nearly level to gently sloping ridgetops on loess covered Illinoian till plains and bedrock plateaus. Slopes range from 0 to 10 percent. The soils are formed in loess. Mean annual air temperature ranges from 54 to 57 degrees F, mean annual precipitation ranges from 35 to 45 inches, frost free period ranges from 180 to 200 days, and elevation ranges from 340 to 1,020 feet above sea level.