Invasive plant species continue to impact Connecticut

In this photo, a close-up of Japanese barberry bush is pictured. The plant has been recognized as an invasive species in many parts of the eastern United States. (J.G. in S.F./Flickr)

Invasive plant species continue to make their way out of residents gardens and into Connecticut’s landscapes, endangering local ecosystems, said CT Invasive Plant Coordinator Nicole Gabelman.

“These are really beautiful plants, they’re pest free, disease free, able to tolerate a wide variety of conditions, reproduce and hold their own,” Gabelman, who works with the Invasive Plants Council, said. “For a lot of people, that’s a perfect plant for them to use in their yard.”

However, the very qualities that makes invasive plants like burning bush, oriental bittersweet and goutweed so desireable to homeowners also help them outcompete native species, stifling their growth.

“One of the problems with these plants is that they didn’t evolve in our native ecosystem so they didn’t evolve with insect pests that eat them or diseases that kill them,” she said.

Donna Ellis, senior extension educator for the University of Connecticut’s Department of Agriculture, Health and Natural Resources, said this results in a loss of biodiversity across the board.

“It affects flora and fauna. A good example would be a butterfly that would need, say, violets in the spring,” Ellis said. “If the violets are outcompeted by the invasive plant, then that butterfly that can only live on those native violets will die off.”

She said this can affect a variety of pollinators, insects that eat pests like aphids and larger mammals such a deer, which often avoid eating on non-native plants.

Gail Reynolds, the master gardener coordinator for Middlesex County, said invasive plant species can also have a negative impact on human health. According to an interdepartmental study at UConn, uncontrolled growth of the Japanese barberry bush can increase the presence of lyme disease infected ticks from 10 per acre to 120 per acre.

Reynolds said it can be difficult to eradicate these species with methods like controlled burns and herbicides because they reproduce with seeds and underground growths.

Volunteers remove an invasive plant species from a tree at the Haddam Meadows State Park cleanup on Saturday, Sept. 26, 2015. (Courtesy/Kate Anderson)

“It’s difficult to say any method is more effective than the others because a lot of the plants are so prolific, ” she said. “You have to spray these plants twice because they’re just so rugged.”

The Department of Energy and Environmental Protection’s Adopt a Park program is one avenue for addressing this problem in Connecticut. Cheryl Czuba, a volunteer at Haddam Meadows State Park, was involved in organizing an oriental bittersweet cleanup this past Saturday.

Czuba said homeowners used to buy the vine for its orange berries before discovering the destructive impact of the species on local environments.

“It’s all over the state, it’s really one of the worst invasive species,” she said. “It kills the trees, it kills the plants, it kills anything that’s in its way and it doesn’t let the natural plants grow.”

Czuba said past invasive plant cleanups at Haddam Meadows have included the Coast Guard along with numerous religious and political leaders from the area, with over 100 people donating more than 300 hours of service in a day.

“People are very passionate about this, I’m amazed how many people we get on a Saturday” she said. “It’s just a gorgeous, gorgeous place and people recognize it, so they want to make it even more beautiful by removing the bittersweet and picking up litter.”

Ellis, who leads Integrated Pest Management program for nursery growers, said one of the best ways to limit the spread of plants like bittersweet is to research native alternatives, before planting a garden.

“People can still enjoy foliage that may turn red in the fall, or grow certain fruits,” she said. “That allows for variety in a garden, but will eliminate some of the invasives that we don’t want to increase in population."


Kimberly Armstrong is a staff writer for The Daily Campus. She can be reached via email at kimberly.armstrong@uconn.edu.