Clarification of secondary area boundaries of North American potentially invasive plant species in the south of the Russian Far East.
Currently, one of the urgent problems of preserving regional flora is the task of identifying invasive species. For this, it is necessary to monitor the distribution of these species and clarify their cultural areas. Landscaping in the South of the Russian Far East makes extensive use of North American woody plants - ash-leaved maple Acer negundo L., desert false indigo Amorpha fruticosa L., false Virginia creeper Parthenocissus inserta (A. Kern.) Fritsch, staghorn sumac Rhus typhina L. Some of them (desert false indigo, black locust Robinia pseudoacacia L.) actively reproduce vegetatively, sometimes creating continuous thickets. This makes it possible to consider them potentially invasive species for the territory of the south of the Far East, although at present they do not intrude into natural coenoses. At the same time, ash-leaved maple, populating disturbed territories, can subsequently grow together with emerging native species (Siberian elm Ulmus pumila L., Manchurian ash Fraxinus mandshurica Rupr., willows Salix spp.), it may be considered as the first stage of its introduction into natural communities. Rarely, it forms monodominant forest stands. Black locust is often intensively vegetatively distributed and, in some cases, is involved in the formation of secondary plant communities. False Virginia creeper and staghorn sumac are found only at the landing sites, but false Virginia creeper can run wild. Ash-leaved maple has the most extensive secondary range (PrimorskyKrai, Khabarovsk Krai), it is somewhat inferior to false Virginia creeper. The remaining species are distributed in Primorsky Krai only. It is important that, together with North American woody plants, in some cases their pests penetrate. Climate change and anthropogenic factors can lead to expansion of the cultural ranges of both North American woody plant species and their pests.