Plants of this genus resemble Medeola virginiana when in a vegetative state. They can be distinguished by the glabrous, hollow stem and absence of a white tuberous rhizome (although one should never dig up a plant suspected of being one of these rare orchids).
1. Flower sessile or nearly so (though the slender elongate ovary may resemble a pedicel); sepals much less than twice as long as petals, clear green; lip whitish to pale green; stem and leaves distinctly glaucous, the plant with a decided gray or hoary aspect.
1. Flower pediceled; sepals about twice as long as petals or longer, purplish; lip greenish yellow, streaked with purple; stem and leaves not glaucous (or the latter somewhat so beneath).
All species found in Isotria
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 13, 2017. http://michiganflora.net/genus.aspx?id=Isotria.