Fungal endophyte infection increases tall fescue's survival, growth, and flowering in a reconstructed prairie

Grasslands in North America are increasingly threatened by land conversion and ecological degradation, prompting restoration efforts to increase native plant species diversity and improve wildlife habitat. A major challenge is the removal and management of nonnative invasive species such as tall fescue ( Schedonorus arundinaceus ), which has a symbiotic association with a fungal endophyte ( Epichloë coenophiala ) that modifies its ecological interactions. Using transplanted clumps of the cultivar Kentucky‐31, we tested the effects of endophyte infection on tall fescue's survival and performance (tiller production, flowering, and basal area) for 5 years in a central Kentucky reconstructed prairie. We predicted that endophyte infected (E+) clumps would have increased performance compared to endophyte‐free (E−) clumps. Overall, E+ clumps had greater survival, tiller production, flowering tiller production, and basal area, but not reproductive effort (proportion of tillers flowering) as compared to E− clumps. However, survival and trends in tiller number and basal area over the 5‐year period suggested experimental tall fescue populations were in decline in the reconstructed prairie, although the E− population declined more rapidly. Our study provides evidence that endophyte infection improved tall fescue's growth and survival in a postreconstruction plant community, at least in the early years following reconstruction, and may increase the invasive potential of this nonnative species in prairie restorations.