Overcoming barriers to restoration: post‐restoration overseeding and topsoil disturbance improve native plant richness and diversity

Restoration outcomes are notoriously difficult to predict and often fall short of restoration goals. Post‐restoration management actions may help overcome barriers to successful establishment, such as dispersal limitations and competition. Layering these management actions to increase the intensity of disturbances may improve restoration outcomes, but they also can be expensive and laborious, depending on the intensity or number of actions implemented. We investigated a series of disturbance intensities on previously restored tallgrass prairies using a randomized block design. Combinations of seeding, harrowing (low intensity disturbance), disking (high intensity disturbance), and herbicide were implemented after a prescribed burn. After 11–14 years, we measured percent cover of all species present to determine long‐term effectiveness. We found that the high intensity disturbance treatment increased native species richness by over 40% and native species Shannon diversity by 15% when compared to control plots. Overall diversity and composition of the plots varied among sites that were treated in different years, indicating that seed mix composition and site conditions were still likely important determinants of community outcomes. Regardless, the consistency of the high intensity management actions to increase site richness and diversity after more than a decade may allow managers to achieve restoration goals, even if later management is limited, justifying the time and resources to enhance existing restorations.