Since 1982, the plant succession and hydrological phenomena were studied in the Jizerka experimental catchment (1.0 km2, the Jizera Mts, Czech Republic). After the clear-cut of spruce plantations (1984–1990), Junco effusi-Calamagrostietum villosae became a new dominant community there. C. villosa has been spreading widely with increased light incomes. In 1991–2005, the re-growth of forest stands, topsoil water content (SWC), and spontaneous plant succession have been studied at the 1,100 m hill-slope transect (elevation from 860 to 980 m). The SWC values increased with forest harvest, and they are still not significantly affected by the re-growth of stands. The canopy development of reforested sites (mainly Picea abies and Pinus sp.) is still low (horizontal canopy density of 0.05–0.25), and does not affect the succession of herbaceous vegetation. The botanical indication reflects changes of SWC in the delay of almost ten years. The Ellenberg s F indicator was found as a powerful tool to describe both the topsoil climate (long-time water phenomena) and the plant succession. However, it cannot address detailed hydrological processes in a short-time scale, and should be employed in combination with an adequate monitoring of environmental factors.