Dendroflora of the polytechnic park and its immediate environs (St. Petersburg, Russia)

New annotated woody plants taxa list of the Peter the Great St.-Petersburg Polytechnic University Park located in Saint-Petersburg (Russia) has been compiled as a result of a years-long survey. As per autumn 2021, arboriflora list of a park includes 142 species and hybrids of 59 genera and 29 families, 23 species represent local species (16,2 %) and 119 species has been introduced from different world regions (83,8 %), 1 species is new for city arboriflora (Fargesia murielae (Gamble) T. P. Yi, Poaceae) while absent in other city parks. Species of varied geographic origin are prevailing in park arboriflora: Euroasiatic – 44 species, North-American – 32 species and Asian – 28 species. Among the families, most abundant as per species and genera count (species/genera), are Rosaceae (47 species from 17 genera), Salicaceae (14/2), Pinaceae (12/4), Oleaceae (7/3), Hydrangeaceae (6/ 2), Betulaceae (6/3), Caprifoliaceae (5/3), Cupressaceae (5/2). The largest genera included in a flora list are Spiraea – 11, Prunus s. l. – 9, Rosa – 7, Salix – 7, Malus– 6, Populus – 6 species. Trees and large shrubs (86,6 %) are the most abundant, while small shrubs, half-shrubs, dwarf shrubs and woody lianas are poorly represented – 19 species (13,4%). The most frequently appearing in the park are the species of singular or rare appearance – 123 species or 86,62% in total. Many species located in this park are rarely cultivated in other city parks (i.e. Padus maackii (Rupr.) Kom., Vitis amurensis Maxim., Picea mariana (Mill.) Britton, Sterns & Poggenb., etc.).