Spatial patterns of female Ailanthus altissima across an urban-to-rural land use gradient Rick E. Landenberger & Timothy A.Warner & James B.McGraw Published online: 20 March 2009 # Springer Science + Business Media, LLC 2009 AbstractAilanthusaltissima isan invasive, dioeciousdeciduous tree common at the interface between urban and rural areas in the mid-Atlantic region, U.S.A. To examine spatial patterns of abundance and associations with land use type, we mapped all mature female trees in nine 89.5 ha plots (805.5 ha total area) across a typical urban-to-ru use gradient using aerial images obtained via remote sensing supplemented by detaile ground referencing. Ruralplots were dominated by forest and had the lowest density of mature females (0.007 females ha −1 ); urban and suburban plots did not differ significantly in mean density (0.37 females ha −1 vs. 0.34 females ha −1 , respectively). Individuals in urban plots were more evenly distributed, but were not associated with a wider variety of land uses and were closer to roads or openings than those in suburban plots. Given less available habitat perunitarea in urban than in suburban environments, these patterns suggest thatAilanthus fits the profile of an invasive species that may be proliferating outward from urban centers. With continued disturbances associated with development in the suburban areas, and timber harvesting in the rural areas, further spread of Ailanthus seems likely. KeywordsInvasion . Dispersion . Ailanthus . Land use . Environmental gradient Introduction Invasive species impose high socioeconomic, cultural, and environmental costs on society (Pimental et al. 2000, 2005).There is growing recognition of the problem by scientists, Urban Ecosyst (2009) 12:437–448 DOI 10.1007/s11252-009-0087-x R. E. Landenberger (*) : T. A. Warner Department of Geology and Geography, West Virginia University, Morgantown, WV 26505-6300, US e-mail: rlanden@mail.wvu.edu T. A. Warner e-mail: tim.warner@mail.wvu.edu J. B. McGraw Department of Biology, West Virginia University, Morgantown, WV 26505-6057, USA e-mail: jmcgraw@wvu.edu