A contribution to the vascular flora of the Sequatchie Valley in Sequatchie County, Tennessee

The vascular flora of the Sequatchie Valley within Sequatchie County, Tennessee was studied for three growing seasons from 2008 through 2010. The Sequatchie Valley is located within the southeastern portion of the Cumberland Plateau and is generally considered to be part of the Cumberland Plateau Physiographic Province. Nevertheless, a number of geological and ecological factors distinguish the Sequatchie Valley from the elevated Cumberland Plateau, suggesting that the floristic composition of the valley may be different from the surrounding region. Although several previous floristic studies have been conducted on the plateau surface, very little attention has been given to the Sequatchie Valley prior to the present study. This contribution documents a total of 767 species representing 379 genera in 116 families. This documentation results in the addition of 513 county records, more than doubling the number of previously documented vascular plant species in Sequatchie County from 468 to 981. Among the noteworthy rare species found were Oenothera parviflora (quite disjunct from its known distributions), Ribes curvatum and Scutellaria montana. Of special interest is the rediscovery of Rudbeckia triloba var. pinnatiloba, designated by the Tennessee Department of Environment and Conservation as a Tennessee endangered species, and previously thought to be extirpated from the state. In addition, eight state records were documented: Carex digitalis var. assymetrica, Spiranthes lacera var. lacera, Bromus latiglumis, Elymus glaucus, Gamochaeta coarctata, Vaccinium angustifolium, Crataegus succulenta, and Verbena scabra