This northeastern and Appalachian species of relatively dry sites with acid soils is close to cernua but generally distinct (FNA 26, W). It differs from cernua (and odorata) as follows: lateral sepals clearly separated along upper margins from adjacent margins of dorsal sepal, the separation abrupt and ca. 1 mm at the base (versus touching or only gradually separated); lip curving at ca. 20-60 degrees from the narrowed base (versus <30 degrees), cuneate at the base (versus cordate to truncate); perianth creamy to greenish-white (versus white to creamy). Flowering tends to be later, as in magnicamporum (Catling & Brown 1983). The species should be searched for further in the field and herbarium.