Growth and competitive abilities of the federally endangered Lindera melissifolia and the potentially invasive Brunnichia ovata in varying densities, hydrologic regimes, and light availabilities

Abstract

Brunnichia ovata (Walter) Shinners is a native, perennial, woody vine with the potential to become an aggressive competitor of the federally endangered shrub Lindera melissifolia (Walt.) Blume. Our study simulated habitat disturbances to hydrologic regime and light availability that may occur naturally, or through active management practices aimed at ensuring the sustainability of L. melissifolia, and we determined the species responses to these changes. First-year plants of L. melissifolia and B. ovata were grown at varying densities, in flooding or nonflooding treatments, and receiving 100%, 47%, or 21% light availabilities. For both species, density effects, in combination with light availability and flooding regime influenced total biomass accumulation. Brunnichia ovata exhibited a high degree of plasticity with respect to biomass allocated between above- and below-ground tissues in response to flooding, whereas biomass allocation in L. melissifolia was relatively unaffected. Interspecific competition occurred primarily in nonflooding treatments. Our study highlighted the complexity of the relationship of L. melissifolia and B. ovata with regard to functional trait responses to changes in abiotic and biotic factors, and indicated that it will be necessary to consider entire plant community responses to mitigate increased competitive interactions and ensure the survival of L. melissifolia populations.