Twenty years of tallgrass prairie restoration in northern Illinois, USA.
Ecosystem restoration projects need to measure progress toward project goals and deliver desired outcomes. This study examines longitudinal plant community data collected from permanent transects at the Nachusa Grasslands preserve in northern Illinois, USA. Managers established permanent transects for repeated plant community monitoring beginning in the mid-1990s. Native plant communities, including rare species, have persisted, or improved with management over two decades. Planted prairies have lower proportions of native species than native prairies but have generally maintained native-dominated communities and in some cases, increased presence of native species. Savannas have shown a distinct transition from shrub-dense communities to herbaceous understories dominated with native species. Restoration efforts at Nachusa Grasslands have been successful at sustaining unique native plant communities through management practices like prescribed fire, brush removal and aggressive invasive species control. As a disturbance-dependent ecosystem that has developed with human management over millennia, tallgrass prairie and savanna can thrive through restoration and active management.