Plants allogamous. Flowers: sepals 3.5–5 mm; rostellum and viscidium absent. 2n = 30.

Flowering late Aug--Oct. Moist, rich woodlands, thickets, old fields, 2d-growth woodlands, wooded hillsides; 0--900 m; Ont.; Ala., Ark., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mich., Miss., Mo., Ohio, Okla., N.C., Pa., S.C., Tenn., Tex., Va., W.Va.

In Spiranthes ovalis var. ovalis, all plants have fully open flowers, and the ovaries swell progressively. In most plants of S. ovalis var. erostellata, the flowers are never quite fully open, and the ovaries are simultaneously swollen on each flower. Because the varieties are largely allopatric, identification can be aided by locality.