Crested coral root is an orchid that lacks chlorophyll, so none of it is green. It obtains nutrients from fungi and decaying organic matter. Compared to Missouri’s other coral roots (which are in a different genus), it is taller and has larger flowers. It grows in Ozark habitats.
Crested coral root is a perennial wildflower growing from thick rhizomes. The stems are yellowish brown, sometimes tinged pink or purple, with 8–25 flowers, in a loose raceme, toward the tip. Leaves are absent, except for a few, small, purplish bracts sheathing the stem. The flowers are about 1 inch wide and have a lower lip that is white with purple veins; it is shallowly 3-lobed, with the central lobe fan-shaped with wavy margins. The remaining petals (2) and sepals (3) are yellow to golden brown and striped with purplish brown; they curve back at their tips. Blooms July–September.
Similar species: Another group of saprophytic orchids are also called coral roots: the genus Corallorhiza. Missouri has two species in that genus. Both are scattered statewide and grow in moist upland and bottomland forest and woodlands, frequently in acidic substrates, also sometimes at the edges of glades in rocky soil. Both tend to form colonies. Both resemble crested coral root, except they are shorter and have smaller, less showy flowers. Their sepals and petals join to form a hood over the lower lip, so the lower lip, as it spreads and flares downward, amounts to the only showy part of the flower; the lower lip is white with magenta-purple markings. Blooming time is the most obvious way to separate them:
- Late coral root (Corallorhiza odontorhiza) blooms August–November. Its sepals and lateral (side) petals are only 3–4 mm long, and there are 2–20 flowers per stem. In Missouri, most populations of this species only have flowers that, by their very structure, must pollinate themselves. They do not cross-pollinate with other plants. This species is slightly less common than C. wisteriana.
- Spring coral root (Corallorhiza wisteriana) blooms April–May, rarely in September. Its sepals and lateral (side) petals are 6–8 mm long, and there are 8–20 flowers per stem.
Height: 6 to 35 inches.
Scattered mostly in the Ozark and Ozark border regions. The overall range is eastern and southwestern United States and Mexico. The northern limit of its range is in Missouri; southern portions of Illinois, Indiana, and Ohio; West Virginia, and Maryland.
Habitat and Conservation
Crested coral root lives in dry upland woodlands and bluff tops on well-drained, calcareous substrates, and along the edges of dolomite glades, frequently under eastern red cedars.
This species is a mycoheterotroph: it acquires its nutrients via fungi connected to the plant’s rhizomes (mycorrhizal fungi). The fungus, with its network of filaments in the soil, digests materials in the soil, and the orchid absorbs nutrients from the fungus. The plant basically parasitizes the fungus. Most plants obtain nutrients through the process of photosynthesis, where chlorophyll, a green pigment in the leaves and stems, converts sunlight, water, and carbon dioxide into sugars to feed the plant — but crested coral root lacks chlorophyll.
Status
Native perennial wildflower. Lacking chlorophyll, it obtains all nutrients via its relationship with fungi. Not a suitable candidate for transplanting, as specimens usually die when transplanted.
This orchid is listed as threatened or endangered in several states where it occurs, including Illinois.
Human Connections
In some ways, this orchid is easy to overlook, because it blends in with late-summer grasses and other vegetation. But when you find one and look closely, you’ll be amazed at the beauty of its small flowers. All orchids have obligate relationships with soil-borne, mycorrhizal fungi — but this one more than most — so they do not tolerate environmental changes well. Thus, they do not transplant well into gardens. Please do not dig up orchids from their natural homes. Instead, take photos and videos of your discoveries. Or get even more creative — capture them with a paintbrush, or write a poem or song about them.
The genus name, Hexalectris, is from Greek hex (six) and alectryon (cock; rooster); it refers to the six raised ridges on the floral lip, which somewhat resemble the crest of a rooster.
The species name, spicata, acknowledges that the flowers are borne in a spike.
The common name “coral root” refers to the rhizomes, which are sturdy, ringlike or twisted, and have projections that resemble marine corals.
Ecosystem Connections
Bees, probably bumblebees, are the likely pollinators of this species. Interestingly, a southwestern relative of crested coral root, var. arizonica (or H. arizonica), is self-pollinating. Its flowers lack a structure, called a rostellum, that would otherwise act to separate the stigma from the stamen (and thus prevent self-pollination). Most orchids have a rostellum, so they must be cross-pollinated in order to produce seed.
You might be familiar with some other Missouri plants that lack chlorophyll. These plants are not green, and they typically lack obvious leaves; instead, their leaves are reduced to small, scalelike flaps:
- In addition to our three coral roots (crested coral root, plus the two coral roots in genus Corallorhiza), there is Indian pipe (Monotropa uniflora) and pinesap (M. hypopitys), both in the heath family. These are all mycoheterotrophs that get nutrients from fungi connected to the roots.
- Other plants that lack chlorophyll get their nutrients by directly parasitizing other plants. Dodders, in the morning glory family, are a prime example. They curl around their host plant’s stem and sink rootlike structures (haustoria) into the host plant, absorbing nutrients. Also, members of the broomrape family (Orobanchaceae) are parasitic on other plants, too, with some species lacking chlorophyll entirely. These species gain nutrients by connecting their roots to the roots of other plants.
The orchid family is one of the largest families of flowering plants, containing some 28,000 species that have been officially described. Many orchid species that grow in remote areas of the tropics have not yet been officially described. Among the families of flowering plants, the aster family (sunflowers, daisies, dandelions, and other composites) is the other heavyweight, with some 32,000 known species, globally. In both families, species are still being described and added.
Compared to their abundance in the tropics, orchids are much less diverse in temperate areas, and Missouri has only 36 species of orchids (and one of them is introduced). By comparison, Missouri has about 330 species in the aster/sunflower family.
