The following is a quote from the website “English Ivy: Arlington County’s Approach” (http://www.fairfaxcounty.gov/nvswcd/newsletter/englishivy.htm):
“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.”
The website further states “Arlington County is out to get English ivy… get rid of it, that is.” The county’s approach is two-fold: “Eradication — Remove English Ivy where possible or manage its growth where complete eradication is impractical” – and “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.”
We need this same approach here in Richmond!
As bad as English Ivy is in and of itself, it is a sort of ”Poster Child” for the various invasive species threatening our ecosystems here in Richmond.
Another, relatively new, threat now invading Richmond rapidly, is Japanese stiltgrass. Both of the following images are by Chris Evans – see http://www.forestryimages.org/search/action.cfm?q=stiltgrass.
Have you seen this in a park or possibly in your own yard:
Here’s another picture showing how this plant can look “beautiful” when in fact it has eliminated the natural vegetation of a forest floor (along with the native birds and insects, e.g. butterflies, that derive their sustenance from the native vegetation):
This article (http://www.fs.fed.us/ficmnew/documents/guidance/FICMNEW_Japanese_stiltgrass_090204.pdf) on Japanese stiltgrass says the following:
“Japanese stiltgrass (Microstegium vimineum) is a dense, shade tolerant mat-forming annual grass that occupies creek banks, floodplains, forest roadsides and trails, damp fields, swamps and eventually all forest areas, especially following natural disturbances. Microstegium can thrive in as little as five percent of normal sunlight. It is very aggressively displacing native plants expanding, for example, from 250 to 382 acres in one year at Huntley Meadow Park in Virginia. The U.S. Forest Service has well over one million acres at risk that will be too late to protect in a very short time frame.… Most vertebrates and invertebrates are lost including several birds that depend on native vegetation as part of their supporting ecosystem.”
We have found this plant growing now in Forest Hill Park, where it especially threatens native plants in the wetland areas near the lake, and even in our own yards!
Japanese stiltgrass is another invasive for which volunteer efforts could be helpful, at least for small areas, because it can be pulled up easily. This must be done only in the fall, however, before it goes to seed. There is a huge “seed bank” so pulling up must be repeated yearly until the plant is eradicated. Pulling up earlier in the year does not work because new germination occurs from the seed bank.
Another invasive that is now a problem for Richmond is the Bradford Pear, discussed elsewhere in this blog. Formerly considered “harmless” because it did not self-pollinate, the introduction of other hybrids is now resulting in successful pollination and the tree is spreading rapidly. Whole hillsides in Forest Hill Park are now being taken over by Bradford Pear.
Students from the College of William and Mary have participated in “work days” in Forest Hill Park where they removed Bradford Pears, privet and English ivy. Their work has shown that VOLUNTEER EFFORTS CAN MAKE A DIFFERENCE!