Habitat fragmentation, low seed germination rates, and herbivory impede conservation efforts for a prairie relict wildflower

Abstract

Fire exclusion, agriculture, and the extirpation of large herbivores have contributed to the loss of early successional plant communities and species across the southeast USA. Georgia aster (Symphyotrichum georgianum (Alexander) G.L. Nesom), a wildflower endemic to the southeast Piedmont, is one species that is thought to have experienced a notable decline. To document the status of S. georgianum in an area in which Piedmont prairie plant communities were historically present (Clemson Experimental Forest, Central, SC), we inventoried patches and flowers and collected seeds for a germination study. We found 37 patches across this 7,082-ha forested landscape, with an average of 25 flowers/patch. Seed germination rates were low, averaging 11%. In addition to fragmentation and low seed-germination rates, camera traps suggest herbivory from eastern cottontail rabbits (Sylvilagus floridanus J.A. Allen) further constrains the population. We conclude that forest management that creates, maintains, and connects early successional habitat is crucial in the conservation of S. georgianum.