Ecological Correlates of Reproductive Output in a Tennessee Population of Short's Bladderpod, Physaria globosa (Brassicaceae)

ABSTRACT Physaria globosa (Brassicaceae), commonly known as Short's Bladderpod, is a federally protected species restricted to Tennessee, Kentucky, and southern Indiana. In 2016, we studied aspects of life history and ecology in a population of P. globosa near Hartsville, Tennessee. Our objectives were to document fecundity-related life history traits and to examine the potential influence of light levels and soil depth on plant growth and reproductive output. In addition, we examined 45 herbarium specimens of P. globosa to assess the potential relationship between taproot size and number of inflorescences per plant. We found the strongest positive relationships between the number of flowering stems per plant and the number of flowers and fruits per plant. Relationships between light levels, soil depth, and biotic factors were only weakly significant. Taproot width was positively correlated with the number of flowering stems on herbarium specimens. Our findings increase the life history and ecology knowledge base available to guide ongoing recovery efforts for the species.