Plant of the Week
Wister's Coralroot (Corallorhiza wisteriana)
By Larry Stritch
Wister’s coralroot orchid is an herbaceous, perennial wildflower with a broad distribution in the southeastern and mid-Atlantic United States, with a western distribution in Arizona and New Mexico and the Rocky Mountains, east into the Black Hills of South Dakota with several disjunct populations in south central Washington, southwest Utah, and central Texas. Wister’s coralroot orchid occurs occasionally as a single aboveground flowering scape or as numerous scapes from a clone.
Corallorhiza wisteriana (Corallorhiza - corallion - coral and rhiza - root; coralroot and wisteriana - for its discover Charles Jones Wister) refers to the underground stems, rhizomes, appearing like an ocean coral.
Corallorhiza wisteriana attains a height of 10 to 50 centimeters. The yellow-green to yellowish-brown to reddish -purple scape emerges from a small coral-shaped rhizome. The leaves are reduced to sheaths surrounding a simple scape (stalk of the inflorescence), yellow to yellowish-brown to reddish-purple. The inflorescence is a lax to dense raceme of few to numerous flowers. Flowers range from fully open and spreading to converging but not closed. The flowers are variously colored, usually reddish to purplish or pure yellow-green, with the petals commonly spotted with purple, the lip is generally white with reddish-purple spots. The fruit is a capsule.
Corallorhiza wisteriana flowers from spring to midsummer. The species occurs in a broad array of coniferous to deciduous habitats in humus rich soils.
Special Note: in the northern part of its range, the yellow-green Corallorhiza wisteriana is often misidentified as Corallorhiza trifida.