Wild Flowers of North Carolina:
also covering Virginia, South Carolina, and Areas of Georgia, Tennessee, Kentucky, West Virginia, Maryland & Delaware
William S. Justice, C. Ritchie Bell, & Anne H.Lindsey
This classic field guide includes photos, as well as information on identifying features and habitat, of wild flowers and flowering trees, shrubs, vines, and weeds found in North Carolina and neighboring states. (It also provides each plant's Vascular Flora of the Carolinas index number.)
University of North Carolina Press.
To select from a dropdown list of genera, type only the first 2-3 letters.
If "briar" doesn't deliver the results you want, try an alternate spelling such as "brier", etc.