One of LCA’s knotweed technicians maps knotweed in the Lewis Creek watershed. Photo credit: Sara Lovitz
Non-native invasive plant species have long threatened the health of ecosystems, wildlife habitat, and populations of native plants in the Lewis Creek watershed. Management can be difficult because they are easily spread via seeds, roots, fragments, animals, and humans. Japanese knotweed is a particularly tough plant to remove. It was introduced from East Asia in the late 1800s, and was planted as an ornamental and for erosion control (but ironically, can actually increase streambank erosion). It spreads primarily by its roots/rhizomes, which can break off during a flood then resprout and form a new colony downstream. In 2024, LCA engaged community members and began a long-term project controlling knotweed (without herbicides) in the Lewis Creek watershed.
In 2024, LCA and volunteers controlled three populations of Japanese knotweed along Lewis Creek near Old Hollow Road in North Ferrisburgh, while educating the public and providing them with the knowledge to perform non-chemical knotweed control on these and other riparian properties. Two LCA knotweed removal technicians, supervised by consultant Michael Bald of Got Weeds?, implemented non-chemical control work at the demonstration site over 16 weeks, with the help of 15 volunteers. Almost weekly volunteer knotweed removal and education sessions were offered on site. A management plan for knotweed removal at the demonstration site in North Ferrisburgh, and for two additional sites in Starksboro was developed. LCA also mapped knotweed in a portion of the Lewis Creek watershed using community science tools (iNaturalist). The LCA website now has educational materials about knotweed, the resulting map of knotweed distribution, and directions that detail how to participate in our iNaturalist project.
In future years, LCA plans to continue a long-term knotweed removal project in North Ferrisburgh, and expand the removal demonstration sites to include sites in Starksboro. LCA will also be continuing our iNaturalist project and we need your help, as we know there are many knotweed patches that haven’t yet been mapped! If you see knotweed growing in the Lewis Creek watershed, please snap a photo and upload it to iNaturalist. And please join our mailing list, so you know when our knotweed removal demonstration days will be held in 2025. You can learn more and sign up at www.lewiscreek.org/knotweed-removal-project
This product has been funded wholly or in part by the United States Environmental Protection Agency under Assistance Agreement #00A00707 to NEIWPCC. The contents of this document do not necessarily reflect the views and policies of the U.S. Environmental Protection Agency, nor does the U.S. EPA endorse trade names or recommend the use of any products, services or enterprises mentioned in this document.
