Colonial settlers brought English ivy and Irish ivy to our continent from Europe. Considered a low-maintenance groundcover, a landscape beautifier and tool for erosion control, ivy was present in the colonies by 1727 and had been introduced to the Pacific Northwest by 1890.
Unfortunately, English ivy – which has more than 400 related cultivars – and Irish ivy, evolved to live in very different regions and to fit niches that are not present here. In the Pacific Northwest they are considered a noxious weed; in 2010, the Oregon Department of Agriculture banned their sale, propagation and transport.
“Ivy is an aggressive invader,” says the Walama Restoration Project, an environmental nonprofit based in Eugene. “Plants common to our forest floors are not equipped to compete with the foreign habits of the ivy. English ivy now poses serious hazards to forested plant communities west of the Cascades.”
This, the US Environmental Protection Agency (EPA) says, includes old-growth forests.
It is an unusually vigorous plant. The EPA notes that “English ivy grows well in sun and shade, can grow year round when deciduous plants are dormant, thrives in droughty and soggy soils, and its waxy leaves retain water and repel herbicides.” Ivy also flowers prolifically and produces berries in late winter when other foods are scarce; the fruits are gratefully consumed, and dispersed widely, by birds.
Ivy does tremendous damage to Oregon neighborhoods, parks and forests. It forms a dense monoculture on the ground that out-competes native plants; it destroys habitat for native wildlife; it climbs trees and kills branches by blocking light and when it continues to climb it can topple trees from its weight – one tree in the Olympic National Park bore up under 2,100 pounds of ivy, according to the King County Department of Natural Resources and Parks.
Worse, ivy is nearly indestructible. “While English ivy is listed as a noxious weed in Oregon,” says the EPA, “it is not quarantined, nor is it listed in other northwestern states.” A single plant can live hundreds of years, and Pacific Northwest animals have no interest in eating it. The Portland No-Ivy League, which has been fighting ivy since 1994, says the only way to eradicate it is by physically removing the plants through “girdling” around the base of trees and methodically pulling every vine and root completely from the ground.
The Salem No-Ivy Coalition, a partnership between area residents, City of Salem Parks staff, representatives from Marion County Soil and Conservation District, Polk County Soil and Water conservation district, watershed councils and others, was formed to control and remove ivy from our own area. With both a Facebook page and blog, the Coalition educates the public on the dangers of ivy and, most importantly, arranges twice monthly “ivy removal” events where volunteers rip out the problem by the roots in area parks.
In September, they were at Wallace Marine Park; in October they were at Orchard View Park and Fairmont Park.
Salem’s Margaret Stephens, the initial force behind the creation of the coalition, credits the City of Salem with the success of these work events. “I can’t say enough good things about the support of the staff in efforts to control invasive plants in our area,” she says. “When there are scheduled volunteer work parties in City parks or natural areas, the City provides the infrastructure to make them happen: registration; fliers; staff to deliver and pick up tools, porta-potties, or other things needed by the volunteers.”
Kevin Martin from Public Works Park Operations was the city liaison at a recent ivy removal party. He brought tools and gloves and helped train a contingent of Chemeketa Community Biology students in ivy removal techniques. “I work with groups of all types,” Martin says. “It’s nice to see people getting out to help the trees and beautify the parks. It’s great for the community.”
Ken Bierly, Chair of the Glen Gibson Watershed Council and a leading member of the No-Ivy Coalition, was out with his clippers the same day, pulling ivy from trunks and branches. “Ivy was originally popular in ornamental planting because it is so effective as a single-species understory; it completely covers the ground. But that’s what makes it so dangerous to our native plants.”
The Salem No-Ivy Coalition is aiming to begin work in Salem’s tiny Waldo Park in early Spring 2015. Waldo Park, at Union and Summer streets near downtown, is one of the smallest parks in the nation, with just one tree – and it is overrun with ivy.
“It is nearing the height of being ‘knee deep’” says Coalition member Virginia Slaughter, “and very importantly, the ivy is beginning to climb the Sequoia redwood tree.” The Sequoia in question is an 82’ heritage tree planted in Salem in 1872. Ivy has already advanced several feet up its trunk.
By the time the work on Waldo Park begins, Stephens says, “the Salem No-Ivy Coalition will have developed a communication plan to tell the community what will happen, and why. We will also develop an ivy removal and restoration plan, [involving] initially removing the ivy as much as possible, then revisiting the site to ensure all ivy roots are gone. Then restoration (replanting) could occur with (hopefully native) plants approved by City Parks.”
Waldo Park makes an ideal spot for the No-Ivy Coalition to draw attention to its work because the tree is in a well-traveled area near central Salem. It “will make an excellent place to have a demonstration/education project about the problems with English Ivy,” Stephens says.
Several members of the Coalition believe that additions are needed to the City Parks budget to allow maintenance staff to work more on controlling invasive plants in our public City areas.
For example, the Civic Center campus where City Hall is located, boasts several banks of ivy groundcover which there are no current plans to eradicate, and the seeds from which spread ivy throughout the community on an ongoing basis. “As it is now,” Stephens says, “Parks’ budget is very stretched, and to assign maintenance staff to work more on invasive plants would mean other Parks maintenance would have to be curtailed.”
Marion County Soil and Water Conservation District offers an Invasive Plant Program (http://www.marionswcd.net/programs/invasive-plant-program/) that can provide assistance in identifying invasive plants and shows management options. The Salem No-Ivy Coalition can be found at https://www.facebook.com/salemnoivycoalition and City of Salem Parks Volunteer Coordinator Tibby Larson can be reached at TALARSON@CityofSalem.NET.