Revegetation seeding provides broad-scale efficacy to inhibit the growth of Rhamnus cathartica seedlings across Minnesota, United States

Introduction: Removal of Common buckthorn (Rhanmus cathartica) can leave legacies that promote rapid reestablishment of managed populations. By sowing native plant seeds into management areas, managed communities can exert greater biotic resistance against reestablishing invasive plants. Despite past success, previous revegetation seeding experiments have been confined to small geographic areas of interest, thereby reducing the scope of inference for efficacy across gradients of light availability and soil composition. Objective: We established a network of citizen scientists to examine the efficacy of revegetation seeding to suppress Common buckthorn seedlings across Minnesota, United States. Methods: Our network comprises 87 sites across Minnesota, each containing six plots. Seeds of Common buckthorn were sown into all plots and half of all plots were sown with a seed mix designed to suppress the growth and survival of Common buckthorn. Two years after sowing, we measured buckthorn survival and growth metrics. Results: The proportion of vegetative cover within seeded plots was 38.1% higher compared to unseeded plots, primarily driven by grass/sedge cover. Revegetation seeding did not decrease buckthorn seedling survival, but did reduce buckthorn height and mass by 17 and 45%, respectively. Conclusions: Our findings underscore the value of using revegetation seeding to improve ecosystem function, reduce the need for continual management inputs, and critically, reduce potential barriers to success for landowners.