The Influence of Vacant Land Presence on Proliferation of Invasive Alien Plant Species: The Case of Ailanthus altissima (Mill.) Swingle Var. altissima

Urban vacant lands have become increasingly important since their potential to become both a resource and a nuisance. Although they can be transformed into green infrastructure, they also pose a threat to human safety due to their role as invasive plant species habitat. In this chapter, we explore the potential effect of the urban land vacancy on the proliferation of Ailanthus altissima (Mill.) Swingle var. altissima. This species is characteristic with allergenic potential, rapid spread, and negative impact on built structures. Thus, it is considered a threat to public health, urban infrastructures, and archeological sites. We tested the hypothesis that vacant lands in urban areas are hotspots for the rapid spread of Ailanthus altissima. Four sites distributed along a transect from the city center to its periphery serve as our study cases. In situ observations on tree morphology and abundance both within vacant lands and nearby urban land were conducted. Based on these examinations, we presented the spatial patterns along the transect, species abundance on various types of land uses, including vacant lands, public, and private green spaces. Findings suggest that due to the high adaptability of the species to degraded habitats, vacant lands act as hotspots for the species’ dispersal.