Orchids of Atlantic Coast Barrier Islands from North Carolina to New York

Abstract

During the past 25 years, we have documented the occurrence of 17 orchid species from Atlantic coast barrier islands from North Carolina to New York, including Calopogon tuberosus, Corallorhiza wisteriana, Cypripedium acaule, Epipactis helleborine, Goodyera pubescens, Habenaria repens, Listera australis, Malaxis spicata, Platanthera cristata, Pogonia ophioglossoides, Spiranthes cernua, S. lacera var. gracilis, S. laciniata, S. odorata, S. praecox, S. vernalis, and Tipularia discolor. For each species, we present data on localities of extant orchid populations, fluctuations in population size, flowering dates, habitat preferences, threats to some populations, results of herbarium and literature searches, and our opinion on the status of orchid species reported by others but not observed by us in the field. Spiranthes vernalis is the most common orchid on mid-Atlantic coast barrier islands. Other species occurring in large (> 1000 individuals) populations include Platanthera cristata, Spiranthes cernua, S. praecox, and Tipularia discolor. Four orchid species occur in moderately large (50 to 100 individuals) populations but have limited distributions, including Calopogon tuberosus, Cypripedium acaule, Epipactus helleborine, and Pogonia ophioglossoides. When analyzed by locality, several regions of high orchid diversity can be identified, including False Cape, Virginia, and the region between and including Nags Head Woods and Kitty Hawk Woods on Bodie Island, North Carolina. These orchid “hot spots” occur in regions that provide a high diversity of habitats.