Authors: Cesar Zamora, Jennifer Fill, Carolina Baruzzi, Javier Salazar-Castro, Dr. Raelene Crandall
Faculty Mentor: Dr. Raelene Crandall
College: College of Agricultural and Life Sciences
Wiregrass (Aristida beyrichiana) is a keystone species in longleaf pine (Pinus palustris) savannas of the southeastern USA. It fuels frequent, ground layer fires known to be essential for maintaining ecosystem function and diversity. Thus, an understanding of the factors that drive wiregrass survival should help explain community dynamics in pine savannas and inform restoration of long unburned sites. As time-since-fire increases in pine savannas, decomposing leaf litter (“duff”) begins to accumulate around plants and have been shown to increase soil heating and mortality of some species, including pines. We investigated whether duff accumulation and wiregrass size affected its survival by monitoring individuals after a prescribed fire in a fire-neglected research unit at Ordway-Swisher Biological Station near Hawthorne, FL. Individual plants were assigned to three treatments: low duff, high duff, and low duff with additional fuels added (3 pine cones). We found that plants had high survival unless they were small (<30 cm2 basal area) and had pine cones added. These results suggest that wiregrass can survive even when fuel loading and fire intensity are high. This is positive news for land managers concerned about grass mortality when reintroducing fire into long-unburned pine savanna sites.