Influence of border area drainage on the vegetation on the slope of the Ruunasoo bog, South-west Estonia

The effect of long-term (over 100 years) drainage on the plant cover of the marginal slope of the Ruunasoo bog (SW-Estonia) was studied. Stable Vaccinium-dominated drained bog pine forest has formed close to the marginal ditch. The forest is expanding over the earlier open S. magellanicum-dominated bog slope and has even reached the hollow-ridge complex. As a result of the self-drainage, and limited throughfall because of dense tree canopy, the Sphagnum carpet is degrading. For the re-naturalization of the plant cover and hydrology of the bog slope, the cutting of trees and closing of ditches are both equally required.