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The Orchidaceae family is characterized by high rates of species rarity and extinction. Translocation efforts are becoming widely used as a means to bolster rare species numbers in situ and are most effective when species habitat requirements are well understood. Platanthera integrilabia is a rare terrestrial orchid endemic to the southeastern United States, and limited research has been done to investigate suitable habitat for this species, despite evidence indicating its ability to tolerate a range of abiotic conditions. We conducted a translocation study to determine the overall success of using tubers for translocation and to investigate how light and herbivory impact translocation emergence, survival, growth, and reproduction. Growth measures were taken monthly during the 2018 and 2019 growing seasons, and light response measures were taken at the beginning of flowering season in both years. Our findings suggest translocation of P. integrilabia tubers yields initial success, especially under dense canopy cover and with limited herbivore access, but low overall rates of flowering and survival could prevent long term establishment. This study highlights the need for a longer-term, comprehensive approach to determine P. integrilabia resource requirements.

Three small (< 1 ha) mountain wetlands located in eastern Kentucky, host populations of two rare orchids, the white fringeless orchid, Platanthera integrilabia, and the crested yellow orchid, Platanthera cristata. Recently, concern has arisen about the persistence of the orchids. To better understand these wetlands and determine if hydrology is affecting the orchid populations, a hydrologic characterization study was initiated in 2009. Each wetland was equipped with a well nest consisting of piezometers, tensiometers, and a shallow well with a data logging pressure transducer. Chemistry and stable isotopes analysis (deuterium and 18O) of groundwater and precipitation were analyzed, and soil, topographic and channel cross-section surveys were conducted. Hydrology data suggest the primary source of water is precipitation and the primary output is evapotranspiration. Between 10 and 30 cm below the soil surface soil and tensiometer data revealed the presence of a weak fragipan, which likely contributes to seasonal ponding at the site. Management recommendations include thinning and construction of debris dams to increase the hydroperiod, surface area, and total potential volume of the wetlands.