Challenges of establishing native versus exotic status of herbarium specimens

In cases where invasive species are presumed to be strictly exotic, the discovery that the species is also native can be disconcerting for researchers and land managers responsible for eradicating an exotic invasive. Such is the case with reed canarygrass (Phalaris arundinacea), for which decades of misinformation led to the call for nationwide control of this species in the United States. However, native populations were first reported by LaVoie and then later confirmed by Casler with molecular analyses. This, coupled with the discovery by Anderson that this species has been used in weavings by Native Americans for centuries, also made the native forms of interest for protection. Identifying the native status of historic, herbarium specimens via molecular analyses is of great interest to determine localities of native populations for confirmation with extant specimens. Genetic-based methods describing DNA polymorphism of reed canary grass are not well developed. The goal of the presented research is to assess the utility of genomic DNA obtained from historic (herbaria) and extant (fresh) tissue of reed canarygrass and the application of using Diversity Arrays Technology sequencing low density for genetic population studies.