It is often described as a lovely, evergreen groundcover. It is also a damaging, invasive species.
English ivy is widely planted, probably ever since ornamental plants were first imported to the United States. Because it is a ground-covering vine that smothers anything in its path, English ivy has been linked to the loss of plant diversity. Winter is the time of year that Hedera helix, or English ivy, makes its presence known. It stays green all year, which is probably one of the reasons why county residents like it in their yards or climbing their mailboxes. English ivy also stands out in natural areas during winter and often is the only green in the forest after native plants have died back for the year.
English ivy is especially dangerous to trees. Once the vine reaches branches, its extra weight can cause those branches to break, injuring the tree and opening an entry point for pathogens or fungus infections. Even if the tree can manage the extra weight from the vines, English ivy will eventually cover all the branches, shading leaves and leading to the tree’s death. English ivy growing on private property can spread to natural areas where it can grow unchecked.
Invasive species are widely considered to be the second-worst cause of ecosystem function degradation. The first is habitat loss, however, invasive species and habitat loss often go hand in hand. To learn more about invasive species removal in Fairfax County parks, visit the Invasive Management Area (IMA) website. IMA has 60 habitat restoration sites around the county, and the Park Authority is always looking for additional IMA volunteers.
Healthy ecosystems provide better air quality, better water quality, more opportunities for wildlife, and plant diversity. All of that means more opportunities for us to discover new things in our natural world. In Fairfax County, with less than 10% of the land protected in natural areas, it is even more important that our natural areas function as best they can.
Take time to assess the area around your house. Can you spot English ivy creeping up trees or mailboxes, or did you plant English ivy in your yard? We have suggestions on our website for replacement plants.
Learn more about English ivy in this online field guide and more about invasive plants in this online discussion archive. Our colleagues in King County, Washington, also have an excellent web page with information about English ivy.
Remove English ivy and replant with a mix of native ground covers like ferns, spring beauty, Dutchman’s breeches and trillium. The native plants will be a much more interesting bunch — and not invasive.
This blog was compiled from Park Authority files and edited by Park Authority Ecologist Erin Stockschlaeder.