Thursday, July 21, 2016

Two Rare Plants

Hexalectris spicata Crested coral-root
Crested coral-root (Hexalectris spicata) is an orchid species listed as potentially threatened in Ohio according to the Ohio Department of Natural Resources rare plants of Ohio list.  You can find the list here  While it is rare for Ohio, and generally uncommon within the preserve, it can often be found along the trails in the Lynx prairie system.  Within the Edge preserve, the species is generally found in dry woods and wooded edges adjacent to prairie openings.  It is often found scattered as a few flowering stems but has been recorded in clumps of 50 or more flowering stems.   Hexalectris spicata is a somewhat fleshy, perennial herb that, except for the flowering stem, is subterranean (it lives entirely underground).  The flowering stem is glabrous, has no leaves, no chlorophyll, and the plant has no roots.  Crested coral-root is a fully myco-heterotrophic plant, a life long epiparasite, that obtains resources through a mycorrhizal relationship with a fungus.  

A close up view of a flower showing the purple crests on the lower lip of the flower. 
The common name "Crested coral-root" refers to the 5 - 7, usually purple, crests found on the floral lip.  The brightly colored flowers would suggest that this plant is looking to attract a pollinator but little to nothing is known about what species might be visiting the flowers.

Crested coral root occurs in many of the areas that the Edge of Appalachia preserve manages with the use of prescribed fire.  We have observed that the plant often responds with numerous flowering stems after the application of prescribed fire.  Crested coral-root typically flowers in mid July through August.

Tall larkspur Delphinium exhaltatum
Tall Larkspur Delphinium exhaltatum is another plant listed as potentially threatened in Ohio.  Tall larkspur is another uncommon species within the Edge but can be locally common where it occurs.  It is found along wooded edges, in old field and prairie openings and occasionally roadside in southern portions of the preserve. 

Typical Tall larkspur flowers.
As the name of the plant suggests, Tall larkspur can reach heights of 6 feet tall when flowering and has a long raceme of up to 30 blue to purple flowers.  Like most other Delphinium species, every part of the plant is poisonous especially the seeds.  Tall larkspur typically flowers beginning in late June into late August / early September and are pollinated predominantly by hummingbirds, butterflies, and other insects.  Tall larkspur is another species of native plant that benefits from the application of prescribed fire.

As with many other wildflowers, white forms can occur. These two plants were found growing side by side near a field of the dark purple ones.
The Edge of Appalachia Preserve has in excess of 85 plant species that are considered rare, which is one of the largest concentrations of rare species in the state.