Weevil Vs. Weed Comes To Virginia

Warm Springs, Va – Mile-a-minute is a non-native weed that is slowly invading Virginia from the north, adding to the growing list of such weeds that plague our forest lands. Biological control of invasive plants has great potential to limit their impacts. Unfortunately, it is difficult to find a suitable biological control that can be safely released into our environment that would not also negatively impact non target, native plants. However, a safe and hopefully effective biological control in the form of a weevil has been mass reared and released into Pennsylvania, Maryland, Delaware and most recently, Virginia.

This year, through the Virginia Department of Agriculture and Consumer Services, a release was made at two locations. The first location was in Hidden Pond Nature Center, owned and managed by the Fairfax County Park Authority which released 1,000 weevils last May. The other location was on lands owned by the Smithsonian Institute near Front Royal and the northern entrance to Shenandoah National Park, which released 500 weevils.

Monitoring over time will reveal how effective these weevils are. In most locations where releases have occurred, significant spread, as well as significant declines in mile-a-minute biomass have been documented. While it is too early to declare success at the two release sites in Virginia, early signs are promising.

There is a long way to go, but combined with additional weevil releases in the future, this may prove to be an important tool in slowly stemming the tide of mile-a-minute. While it is unlikely the weevil will totally eliminate this weed from the environment, the hope is that it will be put in a competitive disadvantage compared to native plants, which will then be able to reestablish themselves in natural habitat.