Gorges State Park is located along the Blue Ridge Escarpment, an area where five streams carry water to the ocean from the divide between the Tennessee Valley drainage and the Atlantic drainage. The upper reaches of the escarpment mountain streams gradually descend, but near the state line the water plunges over waterfalls and rushes through steep-walled gorges.
With such a rugged and contrasting topography contained within a small area, the park includes 21 of the 44 natural community types known in the mountain regions of North Carolina. Nearly 125 rare plant and animal species that occur in the mountain counties of North Carolina are found in the park, in addition to 12 endangered or threatened plant and animal species.
From the rock outcrops of the peaks, to the high-elevation forests, to the spray cliffs surrounding the waterfalls, to the streams themselves, this ecologically rich region has been identified as being of national ecological significance by the state's Natural Heritage Program.
Several plant species more typical of the tropics thrive where the constant spray from the park's numerous waterfalls and plunging whitewater streams showers the sheer rock walls and talus slopes with mist. Scientists are unsure how these species came to grow so far from the tropics. One theory is that spores blew north from the tropics and settled in the region. Or perhaps the species remained in the region from tens of thousands of years ago when a warmer climate existed in North America.
While few larger plants can establish a hold on the steep, slick rocks surrounding the spray cliffs of the gorges, a rich community of ferns, mosses and liverworts grows in the moist, moderate temperatures of the region. Rare species found clinging to the spray cliffs include Carolina star-moss, characterized by its dark green rosettes. The moss is known in the Dominican Republic and also survives in the southern Appalachians. Pringle's aquatic moss, another rare species, attaches itself to rocks under running water. Pringle's moss is found in Mexico, but in the United States it is solely found in the southern Appalachian escarpment region.
Gorge filmy-fern, Appalachian filmy-fern and dwarf filmy-fern, plants with leaves that are only a single cell thick, are also found in the Gorges. The ferns require constant humidity, which is provided by the continuous spray from the waterfalls.
The gorge filmy-fern grows only in the southern Appalachian gorge region. The gorge bottoms are constantly wet with spray, but the steep slopes leading to the rocky, mountain ridges rapidly drain moisture from the terrain. The land supports oak and pine communities typical of dry mountainous regions, but the high rainfall also supports several rare species.
Abundant species include rhododendron and mountain laurel, along with white pine, hickories and red oak. Oconee bells — also known as shortia — are rare flowering plants that also occupy some of the same territory. The plant is most abundant in the gorges region of North Carolina, and because so few populations of the plant are known, Oconee bells are considered to be an endangered species. The plant has single-stalked, white flowers, which stand above the evergreen leaves that form low patches along Escarpment streams.
While the popular animal species of the region include black bear, wild turkey, fox, coyote, wild boar and deer, as well as a variety of squirrels, North Carolina's largest known population of green salamander occurs in the gorges. This secretive salamander hides in the damp, shaded crevices of cliff faces.
The forests of the gorges also provide abundant habitat for neotropical migratory birds, including the largest North Carolina mountain populations of Swainson's warbler. Three fish species — turquoise darter, redeye bass and rosyface chub — have their only North Carolina populations in the park's rivers that are part of the Savannah River drainage. In addition, the nearby Horsepasture River is both a designated federal Wild and Scenic River and state Natural and Scenic River.