Saint-Gaudens National Historic Site Exotic Plant Management Plan

National Park Service

The populations of thirteen exotic plant species in a 133 acre region of Saint-Gaudens NHS were mapped in the summer and fall of 2001: autumn olive, black locust, black swallow-wort, common buckthorn, glossy buckthorn, Japanese barberry, Japanese tree lilac, morrow honeysuckle, multiflora rose, Norway maple, oriental bittersweet, winged burning bush, and yellow flag iris. Information on the position, size, density, and distribution of these populations was stored in a Geographic Information System. Morrow honeysuckle was found to be the most prevalent exotic species. Japanese barberry was also a common and widely distributed invasive plant. Large populations of Japanese tree lilac and Norway maple were found in specific regions of the park. The other nine species were either uncommon or rare. Using the results of inventory, the exotic species were prioritized for removal. Those species that were rare, highly invasive, easy to remove, and present in undisturbed natural areas were the highest priority for control. The sequence of plant species is as follows from highest to lowest priority for removal: glossy buckthorn, autumn olive, burning bush, oriental bittersweet, black locust, black swallow-wort, common buckthorn, multiflora rose, yellow flag iris, Japanese barberry, Norway maple, morrow honeysuckle, and Japanese tree lilac. The appendices include information about the distinguishing characteristics, documented environmental impacts, management goals, and control options for each of the thirteen species. Suggested timetables for invasive plant control are also provided. These timetables are dependent on If funding and staffing permit implementing the recommended control options