| An inventory of the vascular flora of the Tennessee River Gorge (TRG) was conducted between April 2009 and July 2011. The TRG is a 41-km-long river canyon located on the Cumberland Plateau physiographic province within Hamilton and Marion Counties, Tennessee. According to previous ecological surveys, the 4,970 ha (12,281 acres) study area contains 12 natural communities and six unique habitats. A total of 960 specimens were collected. These comprised 692 species and lesser taxa, representing 392 genera from 123 families of vascular plants. Overall, 133 county range extensions were documented for Hamilton and Marion Counties. Ten rare species were reported, including Castanea dentata, Cotinus obovatus, Lonicera dioica, Panax quinquefolius, Scutellaria montana, Viola tripartita var. tripartita, Hydrastis canadensis, Onosmodium bejariense var. hispidissimum, Phemeranthus mengesii, and Polymnia johnbeckii. Of these, four were not reported in any other previous flora of the Cumberland Plateau (Cotinus obovatus, Lonicera dioica, Onosmodium bejariense var. hispidissimum, and Polymnia johnbeckii). Also identified were 92 introduced species, including Albizia julibrissin, Lonicera japonica, Paulownia tomentosa, and Pueraria montana. The largest families represented in the flora were Asteraceae, Poaceae, Cyperaceae and Fabaceae. In addition to the floristic component of this work, a phytogeographical analysis was conducted for the TRG and 12 other Cumberland Plateau floras. This analysis revealed that the floristic composition of the central and southern Cumberland Plateau in Tennessee exhibits southern geographic affinities. Specifically, examination of the phytogeography of the TRG reveals a central geographic distribution to eastern North America; however, 9.5% of the flora has affinities to the southern region, while 3.3% has northern geographic affinities. |
