The Joyce Kilmer Memorial Forest along Little Santeetlah Creek is a rare example of an old growth cove hardwood forest, an extremely diverse forest type unique to the Appalachian Mountains. Although there are many types of trees in Joyce Kilmer, dominant species include poplar, hemlock, red and white oak, basswood, beech, and sycamore. Many of the trees in Joyce Kilmer are over 400 years old. The largest rise to heights of over and have circumferences of up to . The Slickrock Creek basin is coated primarily by a mature second-growth cove hardwood forest, although a substantial old growth stand still exists in its upper watershed.