The modern state of elms (Ulmus L., Ulmaceae) in arboretum of Peter the Great Botanic Garden under conditions of epiphytoty of the Dutch elm disease

The dying of elms (Ulmus L.) at Peter the Great Botanic Garden of the Komarov Botanical Institute RAS in Saint-Petersburg has been observed since the beginning of the 1990’s, soon after the considerable St.-Petersburg climate warming in 1989. During the period from 1981 (the year of the last total inventory of the Botanic Garden) to 2015 three hundred and eighty five trees died, were cut down and removed. They belonged to 12 Ulmus biological and cultivars species: U. laevis – 317 (11 trees are still alive, but all of them are infected, stem dried out from 25 to 70%), U. glabra – 40 (died compl... Mehr ...