Terrestrial Native Species Habitat Restoration: Restore Native Dunes and Oak Savanna
USGS scientists are collaborating with the National Park Service (NPS) to evaluate oak savanna restoration efforts in the Great Lakes by evaluating the success of different treatments in the southern basin and testing the efficacy of interseeding as a restoration tool.
USGS is collaborating with NPS to test different combinations of management actions (native plant reintroductions, chemical and mechanical removal of invaders, soil microbial manipulations, and fire) to determine which are most effective at restoring the high diversity ground layer representative of rare sand dune and oak savanna habitats. Results from this effort will help NPS and other agencies make better-informed management decisions in the future.
Midwestern oak savannas are one of the most endangered ecosystems in the world. For over two decades there has been considerable interest in the status, conservation, and restoration of oak savannas. Many oak savannas are important habitat for plant and animal species of concern, including the endangered Karner Blue butterfly. Across the Great Lakes region, efforts to examine the efficacy of ongoing oak savanna restoration by examining a constellation of sites from Ohio to Wisconsin are being investigated. Investigations are looking at: 1) how well land managers are doing with ground layer restoration; 2) which methods are working to restore oak savannas; and 3) which processes and their interactions are contributing to oak savanna ground layer diversity. In addition, the condition of the ground layer diversity in relation to types of common treatments in the region, such as untreated, burned, thinning of overstory, and seeding are being examined. This broad-based regional perspective, will help develop a greater understanding of the role of ecological processes (fire regime, disturbance, thinning etc) on species richness and ground layer restoration. An experiment to determine the potential for oak savanna ground layer restoration by interseeding on north and south slopes in relation to soil temperature and soil moisture has been initiated. The ground layer flora of oak savannas is quite rich in species, but removal of fire (suppression) causes the decline of the ground layer flora through litter build up and shading. In addition, most savanna plant species lack a long-term seed bank (viable seed buried in the soil) that would respond to restoration by germinating. Thus, in degraded sites, reintroduction of herbs and grasses may be the only way to enhance the ground layer flora. In addition, north slopes may be important microhabitats for some oak savanna species during climatic extremes. These north slopes have been greatly altered through tree invasion after the removal of fire from the landscape. So, the potential for savanna species to occur on north slopes that may be moderated by climatic extremes but were some of the first sites to be invaded by trees as fire suppression commenced are being investigated. Lastly, five demonstration plots for impact of thinning on north slope ground layer vegetation at the Indiana Dunes National Lakeshore have been initiated. Sub canopy trees were cut and herbicide was applied at each site to increase light levels and reduce tree density.
Contributions:
Greater understanding of the factors that contribute to successful oak savanna ground layer restoration.
Partners:
NPS provided staff to assist with four demonstration clearing projects on north slopes.
USGS scientists are collaborating with the National Park Service (NPS) to evaluate oak savanna restoration efforts in the Great Lakes by evaluating the success of different treatments in the southern basin and testing the efficacy of interseeding as a restoration tool.
USGS is collaborating with NPS to test different combinations of management actions (native plant reintroductions, chemical and mechanical removal of invaders, soil microbial manipulations, and fire) to determine which are most effective at restoring the high diversity ground layer representative of rare sand dune and oak savanna habitats. Results from this effort will help NPS and other agencies make better-informed management decisions in the future.
Midwestern oak savannas are one of the most endangered ecosystems in the world. For over two decades there has been considerable interest in the status, conservation, and restoration of oak savannas. Many oak savannas are important habitat for plant and animal species of concern, including the endangered Karner Blue butterfly. Across the Great Lakes region, efforts to examine the efficacy of ongoing oak savanna restoration by examining a constellation of sites from Ohio to Wisconsin are being investigated. Investigations are looking at: 1) how well land managers are doing with ground layer restoration; 2) which methods are working to restore oak savannas; and 3) which processes and their interactions are contributing to oak savanna ground layer diversity. In addition, the condition of the ground layer diversity in relation to types of common treatments in the region, such as untreated, burned, thinning of overstory, and seeding are being examined. This broad-based regional perspective, will help develop a greater understanding of the role of ecological processes (fire regime, disturbance, thinning etc) on species richness and ground layer restoration. An experiment to determine the potential for oak savanna ground layer restoration by interseeding on north and south slopes in relation to soil temperature and soil moisture has been initiated. The ground layer flora of oak savannas is quite rich in species, but removal of fire (suppression) causes the decline of the ground layer flora through litter build up and shading. In addition, most savanna plant species lack a long-term seed bank (viable seed buried in the soil) that would respond to restoration by germinating. Thus, in degraded sites, reintroduction of herbs and grasses may be the only way to enhance the ground layer flora. In addition, north slopes may be important microhabitats for some oak savanna species during climatic extremes. These north slopes have been greatly altered through tree invasion after the removal of fire from the landscape. So, the potential for savanna species to occur on north slopes that may be moderated by climatic extremes but were some of the first sites to be invaded by trees as fire suppression commenced are being investigated. Lastly, five demonstration plots for impact of thinning on north slope ground layer vegetation at the Indiana Dunes National Lakeshore have been initiated. Sub canopy trees were cut and herbicide was applied at each site to increase light levels and reduce tree density.
Contributions:
Greater understanding of the factors that contribute to successful oak savanna ground layer restoration.
Partners:
NPS provided staff to assist with four demonstration clearing projects on north slopes.