This month the NOT WANTED campaign is sponsoring the first in a series of events to remove invasive plants from a visible public site in town. It will be a safe and family-friendly event with tools and expertise provided. Lots of volunteers make it possible to have a real impact on invasive plants. Rain date is Saturday November 14. For more information, call or text David at 860-508-0107.
Great Advice from State Experts
The state’s information and action hub on invasive plants, the Connecticut Invasive Plant Working Group (pronounced “sipwig”) held its annual symposium virtually Oct. 7. It was packed with information, strategies and inspiring stories of success. For a very detailed agenda and speaker resources, contact David at 860-508-0107.
Information and Strategies
Soil disturbance—both wholesale, through construction and earthmoving, and retail, when we pull roots or transplant and leave open soil—is a huge cause of invasive plant spread. Invasive seeds live in the soil for many years and take advantage of any opportunity for light and moisture. Just as boats are washed before moving from one body of water to another to deter the spread of aquatic invasives, construction and landscaping vehicles should be washed between worksites. When we pull a plant and disturb the soil, we should take a minute to press it back into place to help nurture non-invasive plants.
Alternatives: of the 2,800 plants known to exist in our state, about 1,800 are native and 1,000 are non-native. Of the non-natives, only 97 are considered invasive —“non-native plants that are disruptive in a way that causes environmental or economic harm, or harm to human health”—CIPWG. Native plants often are outcompeted and overshadowed by the invasives, but are usually still present and emerge when given the chance.
Native grasses are lifesavers for birds and other wildlife that survive on grass seeds in the dead of winter.Native grasses can be planted where invasive plants have been removed. Examples are Little Bluestem (Schizachyrium scoparium), Big Bluestem (Andropogon gerardii), Switchgrass (Panicum virgatum), and Deer-tongue grass (Panicum clandestinum).
Success Methods
Mugwort (Artemisia vulgaris), described in the September 2020 NOT WANTED, is really tough: tiny root bits can rapidly form whole new colonies. A presenter from Mystic described their success with non-chemical solarization. Mow or cut the mugwort as low as possible, then cover with heavy clear plastic, weighed down well, and leave in place for several months during the growing season. The temperature under the plastic can exceed 110 degrees, destroying the plants above and below ground. Remove the plastic and plant native alternatives.
Japanese knotweed (Polygonum cuspidatum), described in the April 2020 NOT WANTED, is also a super-invasive. East Lyme presenters described their “Power of 3” non-chemical approach. Three tools: clippers/loppers, gloves, industrial strength garbage bags; three actions: cut the knotweed below the lowest node, bag and dispose, repeat; three cuts: May, mid-July, before the end of August; three years: be persistent and patient.
November Invasive Action
Late fall is a great time to pull young Japanese bittersweet, multiflora rose, Russian olive and garlic mustard plants before they get established. As the sun wanes, their hold on the soil weakens.
Japanese bittersweet. Cut larger vines close to the ground, so they have to resprout in shade rather than the full sun on top of whatever they have been climbing, to weaken the plant over time. An alternative with large vines is to cut and carefully paint stumps with liquid herbicide, any time of year except for early spring when the plant is drawing resources up from the roots.
Multiflora Rose. The base of the shrub is more visible after the leaves fall. Use a pole saw or other long handled tool to cut close to the ground by early winter so that heavy snow crushes the dying plants in place and make it easier to follow up next year.
Find more on Granby’s invasive plants at granbyinvasiveplants.weebly.com