Aspetti vegetazionali e floristici del territorio nursino (Umbria - Italia centrale): le serie di vegetazione della roverella (Quercus pubescens s.l.)

We describe a geobotanical study on the vegetation of the Norcia territory (Umbria, central Italy). The natural potential vegetation of the study area is represented by white-oak (Quercus pubescens s.l.) woods. The woods, the shrub vegetation and the grasslands are described in terms of phytosociological units; the relationships between units are used to analyse the vegetation dynamics. Different communities characterized by Quercus pubescens s.l., by Stipa capillata and by Stipa dasyvaginata subsp. apenninicola are described. Moreover, four new species never mentioned for the Umbria region, and seven rare species were found.