Polypodium appalachianum: An Unusual Tree Canopy Epiphyte in the Great Smoky Mountains National Park

The typically lithophilic Polypodium appalachianum was discovered as a canopy epiphyte 35 to 40 m above ground on a horizontal branch of a champion-size Liriodendron tulipifera in the Great Smoky Mountains National Park. Occurring along with this first documentation of P. appalachianum from the tree canopy was an assemblage of normally terrestrial mosses, an unusual assortment of collembola (springtails), and a flightless proturan insect species previously known only from soil and litter. The distinctive features of this canopy habitat may duplicate some ecological conditions usually found only at ground level, establishing the opportunity for translocating an entire community and providing biologists with new insights on the origin of some epiphytes.