Soil Conditions Under Old Field and Forest Cover in Southern Illinois

Abstract A comparison of soil conditions under pine plantations and old fields of the same age was made for three loess‐derived soil types in southern Illinois. Native hardwood stands were used for comparing soil changes under the pine and old‐field seral stages. Characteristics studied included bulk density; hydraulic conductivity; organic content; pH; and exchangeable Ca, Mg, Na, K, and H. Under native hardwoods organic matter, pH, and exchangeable bases were higher, while bulk density was lower than under pine or old‐field cover. Under pine cover bulk density, hydraulic conductivity, and exchangeable base levels were improved over old‐field conditions, but organic matter was higher under the old‐field vegetation. No significant differences were noted in pH. The introduced pine seral stage has considerably ameliorated soil conditions since abandonment from agriculture, and there appears to be a trend toward conditions typical of native hardwood stands.