The most frequent diseases of certain introduced tree species in parks, park forests, and tree rows of Serbia

Various symptoms of diseases, including primarily rotting and dieback of branches were recorded on individual trees of boxelder maple (Acer negundo), honey locust (Gleditsia triacanthos), and green ash (Fraxinus pennsylvanica) during the urban forest health monitoring in the territory of Serbia. This paper presents the most frequent parasitic and saprophytic fungi related to the decline of these tree species. 14 species in total of lignicolous fungi and 1 species that causes necroses and die-back of trees were recorded. The greatest damages were recorded on boxelder maple (Acer negundo) and green ash (Fraxinus pennsylvanica) and the smallest on honey locust (Gleditsia triacanthos). The application of protection strategies should be aimed at reducing the source of inoculum for healthy trees. This can be achieved using various forestry measures, which primarily should be aimed at better phytosanitary treatments of parks and park forests of Serbia, as well as the papers aimed at production of phenotypically adequate trees.