A population of the small whorled pogonia (Isotria medeoloides), a federally threatened species of orchid, has been discovered in Vermont – 120 years after the plant was last seen in the state.

Image credit: Vermont Fish & Wildlife Department

Naturalists had searched extensively for the rare orchid ever since it was last documented in Vermont in 1902, but they have all failed so far. Now, botanists with the Vermont Fish and Wildlife Department confirmed that a small population of the small whorled pogonia has been documented on Winooski Valley Park District conservation land in Chittenden County.

“Discovering a viable population of a federally threatened species unknown in our state for over a century is astounding,” said Vermont Fish and Wildlife Department Botanist Bob Popp. “It’s Vermont’s equivalent of rediscovering the ivory-billed woodpecker.”

The small whorled pogonia is “one of the rarest orchid species east of the Mississippi,” Vermont Fish and Wildlife Department Assistant Botanist Aaron Marcus told CNN. This fact may have to do with the species’ dependence on fungi in its environment, a relationship scientists are still trying to understand.

“A challenge of locating rare orchid populations for conservation is that so much of where they grow is determined by things we can’t easily see or measure, like networks of fungi in the soil,” Marcus said. “These kinds of discoveries are only possible because of the vibrant communities of enthusiasts and professional botanists who work together to understand and document Vermont’s plant diversity.”

Isotria medeoloides, small whorled pogonia. Image credit: Robert H. Mohlenbrock @ USDA-NRCS PLANTS Database / USDA NRCS

The department was first notified of the small whorled pogonia sighting by two community scientists: John Gange of Shelburne and Tom Doubleday of Colchester.

“John is a passionate and skilled botanist who specializes in orchids and closely follows the sightings people report on the community science app iNaturalist,” said Marcus.  “John noticed that birder and retired greenhouse manager Tom Doubleday had used iNaturalist to ask for help identifying an unfamiliar wildflower last July and reached out to us with the news that the small whorled pogonia had very likely just been discovered in Vermont.”

The presence of small whorled pogonia (which was in bloom at the time) was then confirmed by the department, but to protect its location from illegal collection and accidental trampling by passive visitors, Doubleday removed the public coordinates from his post using iNaturalist’s privacy settings.

The department will now work with the Winooski Valley Park District to search for the small whorled pogonia on nearby conservation land and monitor the population to ensure that the species has the best chance to flourish in the state of Vermont.