Corallorhiza wisteriana Conrad

Coral Root


CC = 7
CW = 3
MOC = 59

© SRTurner

Family - Orchidaceae

Habit - Perennial, saprophytic, lacking visible amounts of chlorophyll, glabrous, with highly branched, coral-like rhizomes encircled at regular intervals by scars of successive sheathing bracts.

Stems - Flowering stems to 35 mm, glabrous, brownish or purplish.

Leaves - Absent. Small sheathing bracts present on lower flowering stems.

Corallorhiza_wisteriana_bracts.jpg Sheathing bracts.

© SRTurner

Inflorescences - Racemes with 8-20 flowers.

Corallorhiza_wisteriana_inflorescence.jpg Inflorescence.

© SRTurner

Corallorhiza_wisteriana_buds.jpg Terminal flower buds.

© SRTurner

Flowers - Zygomorphic, perfect. Sepals and lateral petals 6-8 mm long, greenish purple, curved upward and inward and partially overlapping the upper sepal. Lip ovate to obovate, 5-6 mm long, with wavy margins, white with reddish purple spots. Stamens 1, staminodes absent. Ovary 1, unilocular.

Corallorhiza_wisteriana_flower.jpg Flower.

© SRTurner

Corallorhiza_wisteriana_flowers.jpg Flowers.

© SRTurner

Corallorhiza_wisteriana_flowers2.jpg Flowers.

© SRTurner

Fruits - Capsules 8-12 mm long, strongly ribbed, pendent.

Flowering - April - May.

Habitat - Rich forests, often on acidic substrate, glade margins.

Origin - Native to the U.S.

Lookalikes - Corallorhiza odontorhiza; more distantly, Listera.

Other info. - Like many of Missouri's orchids, this one is relatively inconspicuous with small flowers and brownish stems which tend to blend in visually with surrounding leaf litter. It is found across most of Missouri, though is apparently uncommon in the northern third of the state. Its U.S. distribution comprises two distinct bands, one (which includes Missouri) in the southeastern half of the country, the other running from central Montana down through Arizona and New Mexico. Corallorhiza wisteriana is one of two species of the genus found in Missouri. The other (C. odontoriza) has smaller flowers, which are usually cleistogamous, and blooms in the fall.

Photographs taken at Weldon Spring Conservation Area, St. Charles County, MO, 5-4-2011, Matson Hill County Park, St. Charles County, MO, 4-29-2015, and Rocky Mountain National Park, Larimer County, CO, 6-21-2020 (SRTurner).