An old article Orchids of Ohio from The Ohio Naturalist. [Vol. X, No. 2, Dec, 1909.]:
Twenty-one genera and thirty-seven species of orchids are reported from Ohio with two or three others that are doubtful. The species most widely distributed are: Galeorchis spectabilis, Aplectrum spicatum, Blephariglottis psycodes, Gyrostachys cernua, Limodorum tuberosum, Perularia flava, Pogonia
ophioglossoides, Triphora trianthophora, and Blephariglottis lacera. Click here to read full document – Orchids of Ohio.