Isotria medeoloides
(Pursh) Rafinesque
Small Whorled Pogonia

Location Ontario.
First identified in 1977 in Elgin County.
Specific Habitat

Mature mixed forest. In other localities in the U.S.A., the plant has been identified growing in rich leaf litter in hardwood forests.

Flowering Season

Late May and early June.


Height to 25 cm., Stem glaucous, pale green, hollow.
Leaves: 5-6 in a whorl at the top of the stem, light green, elliptic, somewhat pointed. Floral bract is, presumably, one of the leaves.
Flowers: one or two, yellowish green, from the top of the stem. Sepals linear oblong, petals oblanceolate, pale green. Lip greenish white and veined with green, obvate, 3-lobed; lateral lobes narrowly triangular, middle lobe rounded, undulate; disc with longitudinal yellow-green crest which breaks into papillae on the middle lobe.


Often referred to as the rarest orchid east of the Mississippi River. No more than fifty stations have ever been found, of which only thirty-one, including the Canadian one are extant (Stewart, 1983). Rapidly advancing housing developments result in destroyed habitats.
It may be true that some colonies lie dormant for as long as ten or twenty years, awaiting optimum conditions for flowering; however, a colony outside Williamsburg, Virginia has only rarely not produced a visible plant. Isotria medeoloides was officially "designated for protection under Ontario*#39s Endangered Species Act" in 1981.


Orchids of Ontario
Orchids of the Northeast
The Native Orchids of the United states and Canada excluding Florida


© Royal Botanical Gardens, Dr. Donald Gunn Image Collection.