Isotria verticillata
(Muhlenburg ex Willdenow) Rafinesque
Whorled Pogonia

Location Ontario.
Middlesex, Norfolk and Oxford Counties have yielded sightings over the years. In 1985, only Oxford County yielded a blooming plant. Southern Ontario inland from Lake Erie is the northernmost range for this orchid of the eastern United States.
Specific Habitat

Dry to damp hardwoods to mixed forests, and along the mossy edges of fens. Plants usually occur in fairly large colonies, but appear sporadically, often not flowering for several years.

Flowering Season

Late May to early June.

Description

Height: to 30 cm. Stem smooth, slender, purplish, hollow.
Leaves: 5-6 in a whorl at the top of the stem, green, oblong.
Flower: solitary, erect. Sepals purplish, narrowly lanceolate, widely spreading; petals pale yellow-green, obovate, converging over the column; lip obovate, three-lobed, the lateral lobes involute, edged in purple, the middle lobe white, expanded, undulate, the disc with a longitudinal, fleshy ridge.

Comments

To distinguish the non-flowering plant from one of the rare I. Medeoloides, one should compare the stems: The stem of the later is shorter and thicker, whitish green rather than purplish. Both stems are hollow, which distinguishes them from the more slender, fuzzy solid stems of Medeola virginiana (Indian Cucumber) with which it often grows. Also, the leaves of I. Verticulata tend to be a darker green and more blunt than I. medeoloides.

References

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

HabitatPlantFlower

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