LATE CORAL-ROOT

LATE CORAL-ROOT

Corallorhiza odontorhiza
ORCHID (Orchidaceae)

Click on each photo thumbnail to enlarge.

This native orchid has upright yellow-green to purplish stems from 2 to 8 inches tall. The underground portion is swollen and bulb-like. Leaves are reduced to inconspicuous scale-like bracts tightly clasping the stem (A). From 2-20 flowers occur in a raceme on the upper stem, the inconspicuous flowers and larger, more obvious capsules dangling from the ends of short stems (A,C). The tiny flowers less than 1/4 inch long often do not open (cleistogamous) and are believed to be self-pollinated. Those which do open (chasmagomous) consist of a brownish to purplish upper hood-like structure and a broad, white lower lip with wrinkled, purplish edges and purple spots (B). The upper hood-like portion consists of the closely approximated, but unfused, sepals and 2 lateral petals. The lower lip represents the modified central petal. At the base of the flower is a dangling yellowish-green, oval, strongly ribbed capsule.

Upland woods. Rare and irregular at both Fontenelle Forest and Neale Woods. The single stem (Photo A) is the only plant the authors have encountered at Neale Woods since we began this project in 2002. Photos C and D were taken in Fontenelle Forest in 1982, its last known occurrence in that location. Flowering occurs in late August and September. Plants are known to skip a year or more between flowering and do not appear above ground in those years.

Coral-root Orchids produce essentially no chlorophyll and obtain nutrients from organic material in the soil. They could not exist in the absence of certain fungi which digest these organic materials and facilitate their transfer to the plant, a condition known as “mycorrhizal association”. Coral-root Orchids possess many highly branched underground rhizomes which resemble coral, the origin of the common name. The genus name odontorhiza is derived from the Greek, meaning “tooth-root” a reference to the swollen, bulb-like base of the stem.

The content of NatureSearch is provided by dedicated volunteer Naturalists of Fontenelle Forest who strive to provide the most accurate information available. Contributors of the images retain their copyrights. The point of contact for this page is: Neal Ratzlaff.