Biodiversity of the Southern Appalachians

Dr. Steven Price, PhD • May 7, 2026

why is the southern appalachian region so biodiverse?

Most readers are aware that the southern Appalachian Mountains are considered a biodiversity hotspot. According to National Park literature, Great Smoky Mountains National Park—located within this region—is the most biologically diverse park in the entire National Park System. It is often referred to as the “Salamander Capital of the World,” and is home to more than 19,000 documented species of plants and animals, including a greater variety of tree species than any other national park. Reﬂecting its ecological signiﬁcance, the Smokies were designated an International Biosphere Reserve in 1976 and a World Heritage Site in 1983.

If we look more closely, we might ask: what do we really mean by “diversity”? Are we referring to the number of species, the number of genera, the number of families, the presence of endemic species, or the number of species at risk?

And so, another way to think about “diversity” may be to look beyond simple species counts and consider the genetic breadth within an area. For instance, in Tennessee the violet family (Violaceae)includes 28 species across just 2 genera, while the milkweed family (Apocynaceae) has 25 species spread over 8 genera. Similarly, the beech family (Fagaceae) contains 26 species in 3 genera, and the family trilliums belong to (Melanthiaceae or Trilliaceae depending on the classiﬁcation) includes 32 species across 7 genera. These comparisons suggest that the violet family, despite its slightly higher species count, represents less genetic diversity than these other families. Since these other families have more genera, they encompassa wider range of evolutionary variation—in other words, its species are more distinct from one another.

For this reason, modern approaches to identifying biodiversity hotspots emphasize genetic diversity rather than simple species counts. Over the past 25 years, advances in DNA analysis have greatly accelerated our ability to make these comparisons.

For example, it has long been recognized that North America has two major regions of high nave plant diversity: the Paciﬁc Coast/Southwest and the Southeast, with the western region supporting a greater number of species. However, recent DNA studies reveal that the Southeast harbors greater genetic diversity. This suggests that many western species are of more recent origin, while those in the Southeast have a longer evolutionary history.

This pattern also helpexplain why the Southeast exceeds the upper Midwest and Northeast in both species richness and genetic diversity. Much of the northern landscape was heavily impacted by glaciation and later repopulated by plants migrating northward from southern regions, along with contributions from isolated pockets that escaped glacial destruction.

In contrast, the western United States has undergone relatively recent desertiﬁcation and signiﬁcant mountain building, whereas the Southeast was largely spared from glaciation. This long-term environmental stability in the Southeast has allowed plant lineages to persist and diversify over time.

Join us for a full-day Introduction to Plant Identification Class at Rocky Fork State Park on May 30 during which we will embark on an exciting journey through the enchanting world of plant identification. Whether you're an aspiring botanist, a passionate gardener, an environmental enthusiast or simply curious about the flora in east Tennessee, this course is designed to equip you with the fundamental skills and knowledge needed to confidently identify a myriad of plants. Additional dates are available. Learn more at https://www.nolilearn.org/activity/introduction-to-plant-identification-with-botanist-steve-price.

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A group of people are paddling kayaks on a lake.

Kayak Safety & Rescue: Life Lessons in Haro Strait

By Rob Schoborg • July 16, 2026

It was a nearly perfect morning on the Washington state Pacific coast. My wife (Michelle) and I had a delicious breakfast, broke down camp, loaded our rented tandem kayak, and paddled down the sheltered bay that bisects Stewart Island. Along with our guide, Annie, we ran with the tide and a light southwesterly breeze to make the three-mile open water crossing to Henry Island. As we crossed in the 2-foot swells, we were just cruising, enjoying the warmth of the sun, and gazing toward the horizon hoping for our first orca sighting of the trip. Once we passed west of the tip of Henry Island, we headed south a bit and our guide signaled that we would take a break in a field of bull kelp. Thickets of bull kelp make an ideal resting place for sea kayakers because the kelp floats, which are round and 3 to 8 inches across, protrude from the water and break up the momentum of the waves. We stopped for a few minutes, bobbing up and down with the swell, occasionally chatting but mostly taking sips from our water bottles. Over the sound of waves and calling birds, Michelle heard a distant noise. It sounded like a cry for help – or was it a gull? We listened for a few seconds when another, more distinct yell rang out. For an instant we all hesitated, trying to determine the direction of the cries. From our vantage point low to the water, all we could see was dark bull kelp floats scattered across the ocean’s surface. It sounded like the panicked calls were coming from somewhere between us and the shoreline, so we sprinted southeast through the kelp patch toward shore. After we broke through the offshore kelp forest, we spotted two small dark objects on the surface alongside something that looked like a partially submerged log. As the distance closed, the larger object resolved into a flooded green aluminum canoe. The smaller ones were two middle school age boys struggling to reenter the water-filled boat. Every time they tried to enter; the boat would flip. As we neared, they quit trying to enter their boat. Instead, they hung onto the hull of the now inverted canoe and stared quietly as we approached. Michelle and I coasted up on the right side, leaving about a 5-foot gap between our tandem and the canoe, just in case the boys panicked and tried to climb on the deck of our boat before we were prepared. Caution is necessary in a situation like this because a panicking victim can easily capsize a would-be rescuer’s boat - leaving more people in the water. Annie coasted up a similar distance on the left side of the flooded craft. Our first evaluation was that the boys had been in the water for at least fifteen minutes. They were shivering, minimally responsive, and their movements were clumsy. After quickly weighing the options and their condition, we agreed that we could get them out of the water and warm them up more quickly by towing them to shore than by attempting to get the boys back into their boat. We then instructed the closest victim to grab the left perimeter line behind the rear cockpit of our tandem. At first, he refused because he did not want to release the cell phone in his right hand. The impasse was broken when Annie slid her boat up on his left side and convinced him to hand the phone to her. The other boy was similarly coaxed to grab the left stern perimeter line of Annie’s boat. We then started toward shore in the direction of the nearest cottage. When we had closed to within 75 yards of the house, a man came out onto the shore, saw us towing the boys, launched a tandem sit on top kayak, and headed out toward us. The boys, who were shaking with cold, were handed life vests and then hauled aboard the sit on top kayak by their father, while we stabilized the boat. As the reunited family headed back toward shore, we recovered the flooded canoe and towed it to shore. After this brief but adrenaline-filled detour, we continued our journey southwards down the Haro Straight, skirting the shore of Henry Island.