Megaherbivores and Southern Appalachian Grass Balds (original) (raw)

Abstract

The persistence of the grass balds of the southern Appalachians represents an ecological enigma and a conservation dilemma. These high altitude treeless expanses, well known to native Americans and later grazed by white settlers, are now undergoing rapid succession which threatens a unique community of plants and animals. Whatever the balds' origin and in spite of the apparent antiquity of some, much of the botanical literature insists that they are largely an artifact of relatively recent human disturbance, and, except for rare plant preservation, deserve only limited conservation effort. Such an interpretation lacks both a historical perspective and an appreciation of the possible dynamic nature of this community. The presence of both rare, endemic plants and northern relicts requiring open habitat suggests a long evolutionary history. Also, balds that are still grazed today have maintained both their biota and size. We suggest that some balds are indeed ancient and were maintained during the late Pleistocene by mammalian herbivores. Excavations at Saltville, Virginia and elsewhere reveal the presence of up to 20 species of large herbivores, including mammoth, mastodon, bison, horse, tapir, musk ox, and ground sloth until 10,000 years ago. Thereafter, the mountains supported bison, elk, and deer until European settlement. It is likely that, as in many other parts of the world, this special natural community is the result of long-term plant-animal interactions and thus worthy of preservation. Such preservation might best be affected by the use of wild and/or domestic herbivores.