A team of twenty will be targeting Theodore Roosevelt National Park’s South Unit with expanded efforts to control leafy spurge. From September 6-16, Montana Conservation Corp crews, the Northern Great Plains Exotic Plant Management Team (NGP-EPMT) and park personnel will work to control leafy spurge in priority areas. Leafy spurge, a noxious, invasive, exotic plant, has a deep root system and is very difficult to control. Its seeds can lie dormant in the ground and produce seedlings as long as eight years after deposit and, when seed pods burst, the seeds can fly 15 feet away from the plant.
This weed can be found throughout the park; however, experts have targeted areas where the weed could easily spread. Biologist and Data Manager for the NGP-EPMT, Taryn Flesjer stated “waterways, bikeways, hiking trails and horseback riding trails are the key targets because they provide the means for leafy spurge seeds to be picked up and transported somewhere else both within and outside the park.”
“It is very important that we do things on a priority basis and these areas are a high priority,” Prosser says, liaison for the NGP-EPMT. “Horses can get the seeds in their hooves. Cars and mountain bikes can get it in their tires. Hikers can get the seeds in the soles of their shoes.”
The high-priority targets include areas around campsites and along the Little Missouri River, which flows through the park. Park management also decided to create a 300-meter-wide buffer on the east, north, and west boundaries of the park’s South Unit. The Maah Daah Hey Trail, a 96-mile hiking and biking trail, which connects the park’s South and North units, is also targeted as a high priority. Secondary priority locations include areas that are difficult to reach on foot, bike or horseback. The major drainages that flow into the Little Missouri River such as Paddock Creek, Jones Creek, Knutson Creek, Government Creek, and Sheep Creek rise to the top of that list.
Park Superintendent Valerie Naylor is quite pleased with the effort and commented “the park has used an integrated approach, and vital to the success is the distribution of biological control agents for leafy spurge.”
In total the park has released approximately 16 million Apthona spp. biological control agents in 4200 locations throughout the park. Although these flea beetles have proven very successful in controlling leafy spurge, certain areas, such as locations with a high sand content, are not conducive to their establishment. These locations are then targeted by the staff to judiciously apply herbicide to control this aggressive invasive species. In September, the park and the NGP-EPMT expect to control approximately 1000 acres infested with leafy spurge.
Being charged with the stewardship of some of the nation’s remaining wilderness areas can be daunting. “Management is very cautious and very concerned about non-native, invasive weeds,” Naylor says. “Nothing is more important than monitoring the plant diversity because it creates the habitat that maintains animal diversity. As a result, the park only embarks on these types of programs if it is absolutely necessary.”
For more information about Theodore Roosevelt National Park the NGP-EPMT contact Bruce Kaye (Bruce_Kaye@nps.gov), Chief of Interpretation, or Chad Prosser (chad_prosser@nps.gov), Liaison for the Northern Great Plains Exotic Plant Management Team. More information about this and other NPS EPMTs around the U.S. may be found at www.nature.nps.gov/epmt.
