Occurrence of invasive species tree of heaven [Ailanthus altissima (Mill.) Swingle] in the urban area - a case study.
There has been a certain lack of detailed studies dealing with the occurrence and spread of invasive plant species at the local level, which would be an exact guide for local authorities in Slovakia. It is necessary to know where invasive plant species are found, what is their population density and how can be effectively eradicated. For that reason we observed the spread of local populations of invasive woody neophyte tree of heaven [Ailanthus altissima (Mill.) Swingle] in the town of Hlohovec (SW Slovakia) in 2019. We located the plants in habitat type, measured GPS coordinates in the center of the polygons, estimated the area of their occurrence (m2), average height of trees (m), population density (i.m2), the diameter and the circumference of the tree trunk (m) and evaluated impact of management measures against the neophyte compared to unmanaged areas. In 2019, the colonized area totaled 4,673 m2, and A. altissima had not yet occurred in forest ecosystems. The species was found mainly near the Váh River, which accounted for 37% of the total area studied, along the roads (34%), on extensively cultivated fields (9%) and in the parks (9%). A few A. altissima populations were found also along railways (3%), on cemeteries (3%), at abandoned sites (brownfields) (2%), along field roads (2%) and in permanent grasslands (1%). The only management measure was mowing of seedlings in 32% of the total area occupied by tree of heaven.