Beating Back Invading Hordes

Beating Back Invading Hordes

Volunteers clear invasive plants from Woodley Hills Park.

A handful of Woodley Hills residents have largely beaten back an invasion of alien climbing plants that threatened to strangle entire stands of trees at Woodley Hills Park.

David Plummer and his wife, Peggy Bowers, who live nearby, were trained through the Fairfax County Park Authority to lead the team. They chose the park and recruited neighbors to help them remove the Oriental bittersweet and Asian wisteria vines that last year were running amok among trees near the park’s entrance. One tree had already been killed.

In its second year, the Fairfax County Park Authority’s Invasive Management Area (IMA) volunteer program now includes three parks in the Mount Vernon area — Woodley Hills, Paul Springs Park and Huntley Meadows. The program trains volunteers to spot and remove invasive plants, and after three or four training sessions, the volunteers are armed with tools and sent out to recruit a team. The other team members do not need any formal training.

"Invasive plants destroy habitats and tree canopy," said Bowers. Any plant that is not native to the area and tends to have a negative effect on the ecology is considered invasive. Bowers noted that vines like the ones that overtook parts of Woodley Hills, if left unchecked, will strangle trees, squeezing them tightly enough to stop the flow of sap, a process called "girdling." They can also blanket trees, blocking the sunlight.

"It’s also a good way to bring communities together and to meet other citizens who are concerned with the environment and saving our trees," Bowers said of the IMA program.

Fairfax County Park Authority spokesperson Judy Pederson said the scope of the invasive plant problem in the county’s parks is still being determined. "We suspect that it’s a severe problem," she said, noting that more than 300 species of invasive plants had been reported in the parks. So far, the county has identified and targeted about 10 of the worst offenders. "We’ve really just scratched the surface," said Pederson.

MEGHAN FELLOWS, a natural resource specialist for the parks, said the Park Authority estimated that about 30 percent of its land is covered by nonnative species of plants, although she noted that not all of these qualify as invasive.

However, those that are invasive can not only kill off native species, but they also tend to provide fewer animals with habitats than the plant life they push out. Many species of bird, for example, may feed off the invaders and even nest in them, but will not reproduce in them. Some vines, such as Oriental bittersweet or porcelain berries can "become so threatening that people no longer want to go in the woods," said Fellows. "It’s not good for the trees, the wildlife or the people," she said.

Pederson said the Park Authority needed volunteers in order to launch an invasive plant management program because it does not have the budget to hire employees to do the work. "We have a natural resource management plan, and we don’t really have money for that plan," she said. Pederson said the money to support the volunteer program came primarily from the Fairfax County Board of Supervisors, and some came in the form of a Chesapeake Bay Small Watershed Grant from the National Fish and Wildlife Foundation.

Plummer said his team’s first workday was in May, and the neighbors have returned to the park about once a month since then. Typically, a workday involves eight to 10 people working for about three hours. "Some people come all the time, and other people come when they can," said Plummer. All of the work is done with hand tools, including a four-foot "root wrench" that is used to pull up the roots of large vines, and the team does not use any chemicals.

After logging almost 100 volunteer hours in the park, the team had removed something like 40 to 50 cubic yards of invasive plant life, said Bowers. "We’ve still got a few more work days ahead of us before we’re ready to plant here," she said. In October, the group will plant native species of plants in the areas that have been cleared.

Bowers noted that the park will need to be monitored after the new plants are in place, but she said she and her husband would also move on to another park after Woodley Hills is replanted.

"Every little square inch becomes precious at this point in the game in Fairfax County," she said.