Mapping is provisional; presence in Ky. is not verified. This southeastern tree is sometimes treated as a variety of sylvatica, and there is probably some intergradation. It has been reported from adjacent w. Tenn. (Ch), adjacent se. Mo. (Y based on a single old coll.) and perhaps s Ill (K). There are only a few scattered uncertain records from Ky. (M; Clark et al. 2005). A fruiting coll. from ROCK (KY; see also Wharton 1945) may be typical biflora, but even this has been doubted (Burckhalter 1992). N. biflora differs from sylvatica (F, Cr, W) in its fruiting peduncles usually 1-3 cm long (versus 3-5 cm), with 2 flowers (versus 3-5). Leaves are relatively thick and stiff, usually oblanceolate (versus obovate), with obtuse apex (versus acuminate), usually entire (versus often with a few distal teeth). Petioles and young twigs tend to have more persistent hairs (versus largely glabrous). The trunk is swollen or buttressed at base (not in sylvatica); and older bark has vertical furrows (versus vertical and horizontal). Identification is often difficult or impossible with leaves alone.