| Family | Scientific Name | Common Name | Habitat | Distribution | Image |
|---|---|---|---|---|---|
| Orchidaceae | Epipactis gigantea | Giant Helleborine | Wooded streambanks, limestone seepages and springs. | SD, MT and BC south to e. TX, NM, AZ, CA, and Mexico. |  |
| Orchidaceae | Epipactis helleborine | Broad-leaved Helleborine | Mesic and dry-mesic forests, cultivated garden-beds. | Native of Eurasia. This species is becoming very common in the ne. United States and se. Canada. |  |