The aim of bachelor work was to create a complet list of the vascular plants on the studied locality based on field floristic research. The list contains 108 taxa. Within those of nature protection importance, 13 spieces were found including 6 protected species (Campanula serrata, Dactylorhiza fuchsii, Epipactis helleborine, Gladiolus imbricatus, Gymnadenia conopsea, Lycopodium clavatum) and 7 rare and endangered ones (Campanula serrata, Dactylorhiza fuchsii, Epipactis helleborine, Gladiolus imbricatus, Gymnadenia conopsea, Lycopodium clavatum, Platanthera bifolia).Part of this work is also a mutual comparison of existing data with results of the current field research. By this comparison we confirmed the loss of heath areas (Calluna vulgaris), mainly by the reason of afforestation and secondary succession. On the other hand, we confirmed increased coverage of acidophilic grasses. From this reason, it is possible to consider reclassifying of the part of non-forest habitats on the locality of Tretie brehy, from European dry heaths to montain Nardus stricta-rich communities. Proper management – extensive grazing in the study area is proposed, on behalf of species diversity of the vascular plants protection and restriction of succession.