Prescribed Burning for Oak Savanna Management

Since European settlement, there has been an estimated loss of roughly 55% of North America's wetlands. Although there has been a significant reduction in the loss of wetlands since the 1980's, there continues to be a dramatic loss in the functionality of the existing wetlands for wildlife due to the spread of invasive species, such as the hybrid cattail which can create monotypic stands that choke out any open water source. Concurrently, the oak savanna habitat, which was widespread and occupied nearly 50% of the Midwest's landscape, has been diminished to approximately 0.02% of what existed pre-European settlement; making oak savannas one the rarest and most threatened habitats in the United States. The encroachment of many exotic species into the oak savanna, such as hazel, reed canary grass, and buckthorn, has greatly affected the natural processes of the habitat. In both habitats, the losses have resulted in profound negative impacts on the populations and diversity of wildlife and plant species. Oak savanna is a mosaic plant community with multiple successions from open grasslands to mature oak forests, which provides a large structural diversity to support a wide range of species. In order to maintain that mosaic a reliable disturbance is needed. Historically, there were two main sources of disturbance on the landscape, fire and grazing. For over 25 years now, Sherburne National Wildlife Refuge has used fire as a tool to enhance and restore both wetlands and oak savanna, but with increasing costs to conduct prescribed fires and a rapidly decreasing budget, it has become nearly impossible to recreate the historical levels of fire. Without fire, functionality and diversity of these habitats would be lost to monotypic stands of invasive species. To continue to be the most effective in enhancing and restoring these habitats, fire must continue to be used as a the main management tool.