Floristic explore of specially protected natural area «The steppe slopes and beams forests on the valley right bank of the Osetrik river» (Moscow region)

During research 1989, 2022-2023. field route floristic and landscape studies were carried out, as well as a search and analysis of documentary information necessary for reconstructing the history of the formation of modern natural complexes of the reserve «The Steppe slopes and beams forests on the valley right bank of the Osetrik river», which is located in the urban district of Zaraysk, Moscow region. More than 500 herbarium sheets were transferred to the A.K. Skvortsov Herbarium Foundation of Main Botanical Garden of the RAS (MNA). In the protected area, 366 species of vascular plants were identified, of which 61 species were listed for the first time for the urban district of Zaraysk. 12 rare species included in the Red Book of the Moscow Region (2018) were found in the protected areas, including Scrophularia umbrosa Dumort and Corydalis marschalliana (Pall. ex Willd.) Pers. are indicated for the first time. Information is provided on 17 rare and vulnerable taxa from among those in need of constant monitoring; Corydalis intermedia (L.) Merat, Carlina vulgaris L. and Vicia cassubica L. were noted for the first time. Most of the protected, rare and vulnerable plant species are confined to meadows and forests. The alien component of the flora includes 25 taxa, including 12 invasive species.