Oak forests of the alliance Scutellario altissimae–Quercion roboris Goncharenko et al. 2020 in the South of the European part of Russia

The article describes a new association of meso-xerophylous forests in the South of the European part of Russia Poo nemoralis–Quercetum roboris ass. nov. hoc loco, its differentiation from analogous syntaxa is discussed, and new data on the distribution of communities of the alliance Scutellario altissimae–Quercion roboris Goncharenko et al. 2020 on the Russian Plain are done. Vegetation classification was carried out by J. Braun-Blanquet approach based on 470 relevés of forest vegetation, collected by the author in 2007–2021 in the northern and central parts of Rostov, Voronezh and Volgograd Regions. In addition, the analysis included 777 relevés from the phytocenary made by G. M. Zozulin in the same regions in 1960–1980s. Based on the studies carried out, the current area of the alliance can be expanded to the lower reaches of the Don River. For a more adequate reflection of the floristic, ecological and geographical features of its communities, it was proposed to change the composition of the diagnostic species of the alliance and it was recommended to amend the current definition of the order Quercetalia pubescenti-petraeae, expanding its area to Eastern Europe.