Bc. Štefanka Patrik: Diploma thesis, Flora (vascular plants) of the forest ecosystems in the mountain massif Žiar–Ležisko (Vtáčnik Mts). Technical University in Zvolen, Faculty of Forestry, Department of Phytology, advisor: RNDr. Judita Kochjarová, CSc. Grade of qualification: engineer. City: Zvolen, TUZVO, LF, 2020, 88 pages. The work deals with floristic research of forest ecosystems content in selected studied area. Research object was the forest undergrowth of the mountain massif spreading from the elevation point Ležisko to the hill Žiar. The aim of work was the floristic inventory and documentation of forest communities of the study area by phytosociological relevés. The field research was conducted in 2019. During the research brief characteristic of undergrowth has been elaborated. The studied area has been divided into 6 zones, where 6 phytosociological relevés have been noted. Comprehensive list of species in tree-, scrub-, herb- and moss layer was completed. Altogether 117 species of herbs, 18 species of trees and scrubs and 12 species of mosses have been registered in the studied area. There were two significant species of protected plant (herb) species Lychnis coronaria and Waldsteinia geoides found. Zone no.1 was the north-west part from the saddle towards to elevation point Ležisko, there was the fir-beech forest in this area, on the north-west slope and up on the edge. Zone no. 2 was the rocky peak part of the elevation point Ležisko, scree linden-ash forest was in this area developed on stone scree under the top rocks. Zone no. 3 was the part westwards from the saddle towards to hill Žiar, no forest was developed in this area, because it is the glade of previous beech forest (harvesting in stripes from the western side of the ridge Žiar–Ležisko) Zone no. 4 was the stone ridge between the hill Žiar and the elevation point Ležisko, there were mixed oak, oak-ash and maple-ash forests in this area. Opened sunny and rocky spaces were often found in forest, the rocky oak forest steppe was developed on steep hillside from south-east side, on the ridge it met with beech forest from north-west side. Zone no. 5 was the rocky peak of the hill Žiar, there was oak forest developed. Zone no. 6 was the west and north-west hill side situated western from the hill Žiar, there was beech forest with some mountain maple, fire and birch developed on this hillside. Plant species characteristic for both natural and man-made forests were found in studied area. Until these days there was no botanic research conducted in the studied area Žiar–Ležisko and there are no information except those we found out there. Obtained data will be possible to use for further research, science and forestry practice.