American ginseng (Panax quinquefolius L.), goldenseal (Hydrastis canadensis L.) and American bugbane (Actaea podocarpa) in Pennsylvania: habitat, geography, chemistry, and commerce
American ginseng (Panax quinquefolius L.), goldenseal (Hydrastis canadensis L.) and American bugbane (Actaea podocarpa) in Pennsylvania: habitat, geography, chemistry, and commerce