English Ivy: Arlington County's Approach
(Conservation Currents, Northern Virginia Soil and Water Conservation District, March 2003)
Arlington County is out to get English ivy… get rid of it, that is. English ivy, an invasive plant, has contributed to the destruction of tree canopy in that county. Arlington’s Parks, Recreation, and Cultural Resources Department has a two-pronged approach to controlling it.
The first approach is eradication. Remove the English ivy where possible or manage its growth where complete eradication is impractical. The second approach is citizen education. Teach the public to identify it, understand the damage it causes, remove it from personal property, and choose less invasive groundcovers in its place.
While there are many invasive plants in Virginia, Arlington County chose to focus its outreach program on English Ivy. “It’s a big problem in an urban area because people are still planting it,” said a Park official.
English ivy (Hedera helix) is an attractive green plant that traditionally has been appreciated for its rapid growth, its suppression of any other plant growth, and its ease in cultivation. But these characteristics also are the reasons why it is devastating to land areas populated by native species.
English ivy is an aggressive, invasive, introduced species with no natural controls in our ecosystem. It spreads fast from its roots, vines, and seeds. The vines shade out and replace the wildflowers, shrubs, and young trees of the natural forest understory. The vines weaken trees by keeping the bark damp and blocking sunlight. The vines eliminate the diverse varieties of plants needed by birds and other wildlife to provide food and shelter through each of the seasons.
There are more than 100 volunteers spreading the word about invasives and assisting with eradication. Since July 2002, control efforts on county parkland has exceeded 10 acres. In addition to English ivy, the county is battling porcelain berry, kudzu, Japanese stiltgrass, Japanese honeysuckle, and Japanese knotweed. “Although mechanical control seems to work on small patches, we have found that the most efficient method of eradication for large areas is spraying,” said park officials.
The program tries to go to areas where it will have the most impact. “A heavily infested 20-acre park is too big for us to tackle with the resources available. But in a six-acre park where one acre is infested, we can make a difference.”
Much of what is done depends on where volunteers are interested in working. Many volunteers want to remove invasive plants and help with monitoring in parks close to their homes. “We try to encourage those efforts by helping to organize volunteer events and backing up volunteer work with staff work in the same areas,” the invasive plant coordinator said.
For people who won’t let go of their English ivy, invasive plant volunteers provide plenty of information about controlling the ivy around trees so it doesn't creep up and flower. “Generally, the plant must be at least six years old AND six feet high before it flowers and produces seed,” she said.
Park officials are full of optimism about the public response to the invasive control program. “We believe that if you give people a choice between English ivy and a more environmentally friendly plant, the people would be willing to pay a little more to help the environment rather than harm it.”
Last fall, Arlington County proposed legislation to declare English ivy a noxious weed in the State of Virginia. Listing English ivy as a noxious weed would require the state to regulate the sale and transport of it and allow local governments to seek financial and technical assistance from the state in eradicating it.
A bill sponsored by Senator Mary Margaret Whipple was introduced in the Virginia General Assembly, referred to committee, and then withdrawn by the sponsor. Later, Senator Whipple introduced a related bill that was referred to committee where it was tabled indefinitely.
Arlington County Parks staff were disappointed but not disheartened. “Even though our legislative proposal was not successful, we did succeed in raising the issue in the public’s mind.”
To learn about volunteer opportunities in Arlington’s Remove Invasive Plant Program, email Sarah Archer or call 703-228-1862.