Ammophila breviligulata: Implications of using non-local plant sources for native plant restorations in Minnesota

Ecological restoration projects often rely upon the introduction of nonlocal propagules, such as seed or clonal fragments, to replace or supplement threatened populations. In Minnesota, historical dune restoration projects introduced nonlocal propagules of Ammophila breviligulata from Michigan to augment the threatened native population. Despite the good intentions of such efforts, there is mounting concern over the source and genetic history of the propagules used in these restoration projects. If the MN and MI populations are substantially genetically diverged, genetic mixing between the two populations could lead to outbreeding depression; characterized by high mortality, slower growth, and reduced seed production. the negative effects of inbreeding depression, commonly referred to as hybrid vigor. Additionally, introduced genotypes of beachgrass from MI could compete with threatened native genotypes and become dominant if they possess a fitness advantage or numerical advantage; occurring through either vegetative spread via rhizomes or through the recruitment of seedlings.