Conservation and recovery of Astragalus bibullatus
We are working on multiple research projects focused on the conservation and recovery of the federally endangered and limestone cedar glade (LCG) endemic, Astragalus bibullatus (Pyne’s ground-plum). Well known among the botanical community for its unique and endemic flora, LCG’s are rare edaphic grasslands restricted primarily to the Nashville Basin (central TN) and seriously threatened by habitat loss, fragmentation, and altered hydrology and disturbance regimes. In partnership with the United States Fish and Wildlife Service (USFWS) and the Tennessee Department of Environment and Conservation's (TDEC) Division of Natural Areas, our research is supporting science-based recovery actions to reduce the extinction risk of Pyne’s ground-plum, and to restore and manage this unique habitat at the landscape-scale. To learn more, see a video of our research featured on Tennessee's Wildside.
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Woody encroachment, drought, and demographyUnderstanding how natural and anthropogenic variation influence population growth is a critical first step in reducing the extinction risk of rare plants. We have been monitoring the demographic rates of Pyne’s ground-plum in permanent plots and transects across a range of microenvironments and site histories, and using controlled experiments to understand the drivers of population growth. Our results have shown that:
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Adaptive reintroduction experimentsReintroductions are increasingly used to expand the occupancy and abundance of endangered species in order to reduce their extinction risk. The Missouri Botanical Garden has been working on a long-term experimental reintroduction program with Pyne’s ground-plum. We are taking an adaptive reintroduction approach whereby sequential experiments test specific hypotheses on how microenvironment, propagule stage, transplant season, genetic origin, and vertebrate herbivores affect demographic vital rates. We are working across several natural areas in the Nashville Basin to increase the occupancy of Pyne’s ground-plum in its historical range. To date, we have determined:
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Funding: We thank the United States Fish and Wildllife Service, Tennessee Department of Environment & Conservation, National Park Service, and National Science Foundation for funding our work.