Naturalization of Rare Caucasian Plants in Moscow in the Tsitsin Main Botanical Garden of the Russian Academy of Sciences

Abstract

A long‑term introduction study demonstrated the successful adaptation of rare Caucasian species to Moscow’s climatic conditions, confirming the possibility of preserving the gene pool of protected plants outside their natural habitats. Moreover, most of the tested species do not exhibit pronounced invasive activity, making them promising for use in urban landscaping. A key factor in successful adaptation is the similarity of soil and climatic conditions between the native range and the point of introduction; representatives of mountain forests, tall grasses, subalpine meadows, and meadow-steppe communities demonstrated the greatest resistance. None of the species confined to upland xerophytic, semi-desert, highland, or subtropical habitats naturalized during the entire observation period. Despite the resistance of many highly decorative protected species to Moscow’s climatic conditions, their active expansion is limited by anthropogenic impact. At the same time, among the rare plants included in the Red Data Book of Russia, individual taxa with signs of naturalization were identified: Allium paradoxum (M. Bieb.) G. Don (2008 edition) is classified as an invasive species, Staphylea pinnata L. (2008 edition) forms thickets in the undergrowth through self-seeding, and Taxus baccata L. (2024 edition) forms self-seeding outside the collection area. These observations confirm that individual rare species demonstrate the ability to expand in anthropogenically transformed conditions.