By Danielle Hubing, archives specialist at NMSC
Non-native plants have long been an issue in Acadia National Park, as well as in many other parks throughout country. Take a look at these photograhs and see if you can determine which of these plants is not native to Acadia National Park.
|A. Witch Hazel|
|B. Canada Lily|
|C. Purple Loosestrife|
|D. New York Fern|
|E. Sugar maple|
|F. Cinnamon Fern|
All photographs courtesy of the United States Department of Agriculture: Natural Resources Conservation Service: Plants Database: http://plants.usda.gov/
If you answered “C. Purple Loosestrife” you are right! Other plants in the park that are commonly mistaken as native include: black locust, rugosa rose, garden lupine, Norway maple, highbush, cranberry, ash-leaved maple and Japanese barberry.
Many people assume that purple loosestrife is native to Maine because it is so widespread throughout the state. It is not native, and once it is introduced to an area, it spreads very quickly, displacing native plants, especially in high-value habitats like wetlands. Purple loosestrife is present in at least 43 states and considered to be a noxious weed in 33 of them. In 1988 it was considered the most threating invasive plant in Acadia National Park.
Acadia National Park’s Resource Management Records (1854-2012) Collection chronicles the non-native plant management and revegetation (the process of replanting native plants to restore the landscape to its original form) efforts of the park, of which managing purple loosestrife was a major focus. Beginning in 1988, the Vegetation Management Division documented native and non-native plants in the park. Purple loosestrife was identified as a major environmental threat because it infringes upon food plants for wildlife. An aggressive management program of surveying, spraying and monitoring was initiated in 1988. Surveying occurred by foot, by canoe, by car and by bicycle. Once the areas where purple loosestrife could be found were documented each individual plant was hand sprayed with a 1% glysophate herbicide solution. Post-spray mortality was evaluated and flowering heads were removed to prevent seeds from spreading. The survey/spray data sheets for 1998-2005 can be found in the park’s Resource Management Records collection.
Today, twenty-seven non-native invasive plants are actively monitored and managed in the park, including: garlic mustard, shrub honeysuckles, Canada thistle, glossy buckthorn, foxglove, Japanese knotweed, giant hogweed, and coltsfoot.
Park staff has worked closely with garden clubs to help encourage the sale of native plants that can be used for landscaping. Park staff also maintained records of plant species found on federal property, surveyed for endangered and threatened plants and directed revegetation efforts to heal disturbed or trampled areas. Seeds of native plants were collected throughout the park and transported to Natural Resource Conservation Service nurseries in New Jersey and New York to be raised to transplant size. Prior to any construction on park lands, flora surveys were conducted to gather baseline data on rare or invasive plants. Sometimes, prior to construction native plants were salvaged and used for revegetation projects. Sites in need of revegetation were prioritized, high-priority sites were re-planted with native transplants, and the success of revegetation was monitored. Revegetation project notes are included in the park’s Resource Management Records collection.
Natural resource collections such as the Acadia National Park Resource Management Records can be invaluable to parks. The collection holds Reports and Annual Summaries for Purple Loosestrife Management from 1988-2005; 2007. In 2006 budget cutbacks resulted in purple loosestrife not actively being sprayed. Monitoring showed that the plant was beginning to spread to areas where it had been previously eradicated. Since then, purple loosestrife has been actively monitored and managed. Annual records provide important information to managers so they know where purple loosestrife has been previously found within the park, allowing those areas to be monitored to prevent future spread of the plant, protecting important wetlands and wildlife habitats.