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One need only peruse a nursery catalog or visit a localgardening center to realize the enormous array of plant choices available to the everyday American gar-dener. Unfortunately, this wealth of consumer choices comes at a steep cost. Non-native plants introduced through the horticulture trade often become invasive (Mack and Lonsdale 2001; Reichard and White 2001), which we define here as introduced species whose popu-lations are surviving and reproducing beyond the loca-tion of introduction (sensu Blackburn et al. 2011). Although only a portion of species that become invasive cause ecological damage (Williamson and Fitter 1996; Sax et al. 2002), and some have benefited biodiversity (Davis et al. 2011; Schlaepfer et al. 2011), invasive plants as a whole substantially reduce native species abundance and diversity (Vilà et al. 2011) and alter ecosystem func