A profusion of vegetation defines the Great Smokies; it has one of the richest and most diverse collections of flora in the world. The park is about 95% forested, home to almost 6,000 known species of wildflowers, plants, and trees. Many call the Smokies the "wildflower national park," as it has more flowering plants than any other U.S. national park. In all, typically in October, hundreds of thousands of visitors jam the roads of the park to view the autumn leaf colors.

You can see wildflowers in bloom virtually year-round: ephemerals such as trillium and columbine in late winter and early spring; bright red cardinal flowers, orange butterfly weed, and black-eyed Susans in summer; and Joe-pye weed, asters, and mountain gentian in the fall. However, the best time to see wildflowers in the park is the spring, especially April and early May. The second-best time to see the floral display is early summer. From early to mid-June to mid-July, the hillsides and heath balds blaze with the orange of flame azaleas, the white and pink of mountain laurel, and the purple and white of rhododendron.

Living in Great Smoky Mountains National Park are some 66 species of mammals, more than 200 varieties of birds, 50 native fish species, and more than 80 types of reptiles and amphibians.

The North American black bear is the symbol of the Smokies. Bear populations vary year to year, but biologists think that up to 1,500 bears are in the park, a density of about two per square mile. Many visitors to the park see bears, although sightings are never guaranteed.

The National Park Service has helped reintroduce elk, river otters, and peregrine falcons to the Smokies. Attempts to reintroduce red wolves failed, though visitors occasionally report seeing what they believe is a wolf.

Because of the high elevation of much of the park, you'll see birds here usually seen in more northern areas, including the common raven and the ruffed grouse.

For a few short weeks, usually from late May to mid-June, synchronous fireflies put on an amazing light show. In this illuminated mating dance, the male Photinus fireflies blink four to eight times in the air, then wait about six seconds for the females on the ground to return a double-blink response. Inside the park, the Elkmont camping area on the Tennessee side is a popular place to see the fireflies. The Joyce Kilmer Memorial Forest just outside the park near Robbinsville, North Carolina, is another great place to see them.

Altogether, some 17,000 species of plants, animals, and invertebrates have been documented in the park, and scientists believe up to 80,000 additional species of life, as yet unidentified, may exist here.