This orchid may be the poster child for non-native invasive plants. In North America, this species has widely naturalized across the Northeast and Midwest, the West Coast and extends into Canada. Found in a variety of disturbed habitats such as lawns, sidewalks, gardens, and roadsides, this species also grows in forests, swamps, and riverbeds. It grows so aggressively that some states, such as Wisconsin, consider this orchid a noxious weed. Herbicides are reported not to be effective, so digging out the underground rhizome may be the only way to control this invader. Two other non-native Epipactis species have been reported in North America.
Photo © David McAdoo