Abstract: Fifty-seven county records, representing 56 species and 28 vascular plant families, are reported here as new additions to the Virginia flora. All voucher specimen are housed in the Radford University Herbarium (RUHV). Our study examined the entirety of the nearly 10,000-specimen collection at Radford University. Each specimen was manually cross-referenced with current county records; when potentially new county records were discovered, identifications were verified. We also determined whether any new county records were listed as state-, federally-, or globally-imperiled. Among the county records, we also determined the number and distribution of non-native and potentially invasive species. Most specimens were collected from Virginia’s Appalachian Mountain region. Of the 56 species, two have conservation ratings of globally and state “vulnerable” (Monotropsis odorata and Aconitum reclinatum). Several others are “globally secure” but of concern in Virginia, including two state-imperiled species (Calopogon tuberosus and Stylophorum diphyllum) and three vulnerable species (Carex shortiana, Pogonia ophioglossoides, and Stachys latidens). We also document the first county records of three invasive species (Ludwigia grandiflora ssp. hexapetala, Poa trivialis, and Securigeria varia). These contributions show how smaller herbarium collections contribute to our understanding of Virginia’s natural history and native and non-native flora.

Saxifraga tridactylites (Saxifragaceae), an annual herb native to northwest Africa, southwestern Asia, Europe, northeastern Iran, and western Russia, has rapidly naturalized in two geographically distinct areas of the United States: the Southeast and the Northwest. In the Southeast, the spread has been exceedingly fast and poses a potential threat to xeric limestone habitats of the Interior Low Plateau and Ridge and Valley physiographic provinces. Prior to our work, S. tridactylites appeared to be an insignificant introduction, only documented in a few North American locations in British Columbia and Oregon. Here, we show that the North American distribution is much greater than previously reported, with records from four counties in the Northwest and 53 counties in the Southeast: northern Alabama (14 counties), northwest Georgia (two counties) northern Mississippi (five counties), and southern Tennessee (32 counties). To our knowledge, it has not yet dispersed into Arkansas, Kentucky, or North Carolina.