|Keys to Nature
|Key to the species of Corallorhiza (Orchidaceae) in the Chicago Region|
Key to the species of Corallorhiza (Orchidaceae) in the Chicago Region
William Alverson, Jennie Kuse
Adapted (by Jennie Kluse and Bil Alverson) from a key to the orchids of Wisconsin by Jeffrey R. Hapeman (www.botany.wisc.edu/orchids), Mike Homoya's Orchids of Indiana (1993, Indiana University Press), and Fred Case's Orchids of the Western Great Lakes Region (1987, Cranbrook Institute of Science).
1. Flowering from April to mid-June – 2.
1. Flowering from late July to October – 3.
2. Stems green or yellowish-green; flowers whitish, with a three-lobed, white lip petal without spots; sepals spread out; rare in our region, known only from the Lake Michigan Dunes – Corallorhiza trifida
2. Stems yellowish-brown, orange-brown, or purplish-brown; flowers yellowish-brown to purplish-brown, with an unlobed, white lip petal with purple spots; sepals not spread out, but instead held close to the petals; rare in our region, known only from St. Joseph County, Indiana – Corallorhiza wisteriana
3. Lip petal three-lobed or with teeth-like lobes near base; the other petals and sepals usually spreading away from each other so that the flower has an "open look" (as M. Homoya aptly stated) – Corallorhiza maculata
3. Lip petal without lobes; the other petals and sepals fold foward towards each other so that the flower has a "closed look" (M. Homoya) - Corallorhiza odontorhiza