Corallorhiza mertensiana
Western coralroot, Western Coralroot
(c) Tom Hilton, some rights reserved (CC BY), uploaded by Tom Hilton · licence
Family: Orchidaceae · Type: Herb · Native
Corallorhiza mertensiana (Western coralroot) is a native California herb in the Orchidaceae family, recognized by deep pink/red coloration and dark red lip veins.
Western coralroot is a California native orchid found in northwestern California (excluding North Coast Ranges Interior) in shaded to open mixed-evergreen and conifer forests at elevations below 2,200 meters. Flowering from May to July, this delicate orchid produces deep pink to red flowers with yellow or dark red veins, featuring a distinctive lip with two acute lateral lobes and irregularly toothed edges. Growing 15 to 45 centimeters tall with generally reddish stems, it emerges from decomposing leaf litter in forest understories. Its flowers feature sepals 7 to 10 millimeters long, with lateral petals in deep pink to red and a column that is yellowish with a purple base. The plant produces fruits 15 to 25 millimeters long, reflecting its unique coral-like growth pattern characteristic of coralroot orchids.
Identification and appearance
Key characters: 3 sympatric species; distinguished by deep pink/red coloration and dark red lip veins
Habitat and range
Habitat: Shaded to open mixed-evergreen or conifer forest, in decomposing leaf litter
Elevation: < 2200 m
California counties: Trinity, Del Norte, Siskiyou, El Dorado, Lake, Mendocino, Butte, Humboldt, Tehama, Sonoma
Outside California: to Alaska, Montana, Wyoming
Bloom period
Corallorhiza mertensiana blooms May-Jul.
How to tell it apart
vs Pyrola: Corallorhiza is completely leafless; Pyrola has basal rosette of green evergreen leaves.; vs Pterospora: Corallorhiza has multiple small orchid flowers; Pterospora has urn-shaped flowers and sticky-hairy reddish stems.; vs Sarcodes: Corallorhiza has small distinct orchid flowers; Sarcodes has bright red fleshy bell-shaped flowers.; vs Epipactis: Corallorhiza is entirely brown/purple toned; Epipactis has green leafy stems.; vs Spiranthes: Corallorhiza is brown/pink/purple throughout; Spiranthes has green stems with white flowers in spiral.
Frequently asked questions
Is Corallorhiza mertensiana native to California?
Yes. Corallorhiza mertensiana is native to California (recorded as native).
When does Corallorhiza mertensiana bloom?
Corallorhiza mertensiana blooms May-Jul.
Where in California does Corallorhiza mertensiana grow?
Corallorhiza mertensiana occurs in Trinity, Del Norte, Siskiyou, El Dorado, Lake, Mendocino, Butte, Humboldt and other counties, at elevations of < 2200 m.
What plant family does Corallorhiza mertensiana belong to?
Corallorhiza mertensiana is in the Orchidaceae family, genus Corallorhiza.
What habitat does Corallorhiza mertensiana grow in?
Corallorhiza mertensiana grows in Shaded to open mixed-evergreen or conifer forest, in decomposing leaf litter.
Related species
Other California species in the same genus, family, or bioregion.
- Corallorhiza sp. — Coralroot
- Corallorhiza striata — Striped coralroot
- Corallorhiza trifida — Northern coralroot
- Corallorhiza maculata — Spotted coralroot
- Corallorhiza maculata var. maculata — Summer coralroot
- Corallorhiza maculata var. occidentalis — Summer coralroot
- Cypripedium californicum — California lady's-slipper
Sources: Jepson eFlora · Index of California Plant Names · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.