Mile-a-minute vine, a rapidly spreading invasive weed that chokes out native plants and damages habitat for native wildlife, has been found in five more towns recently including Groton and Old Saybrook.

The vine, originally from eastern Asia, has been confirmed in 31 Connecticut towns, including Lyme and Stonington. Scientists at the University of Connecticut, the state Department of Energy and Environmental Protection and the Connecticut Agricultural Experiment Station are continuing efforts to control the spread, including alerting officials in towns where it is found. The vine was first found in Fairfield County in 1997.

"We're encouraging each town to alert their residents," Donna Ellis, senior extension educator at UConn, said Friday.

Homeowners and owners of private and public lands are encouraged to hand-pull the vine this fall.

"They should also get out as soon as they can in the spring," Ellis said.

The vine, with heart-shaped leaves, spreads by seeds and quickly grows into dense mats that smother native vegetation.

Logan Senack, the state's invasive plant coordinator, encouraged residents to get outdoors and look for mile-a-minute in their yards.

"If you find a plant you think might be mile-a-minute, please let us know before pulling it up or throwing it away," he said. "We may need to collect more information about the plant, confirm that it is mile-a-minute and not a similar species, and look for the beneficial insects at the site before the plants are removed."

In 2009, scientists from UConn and the experiment station released the stem-boring weevil at several sites as a biological control for mile-a-minute. The insects are expected to help reduce populations of mile-a-minute a few years after release. Last year, the insects were released at sites along the Shetucket River in Sprague that were heavily infested with mile-a-minute. The insects are establishing themselves well but have not yet begun to make a major impact on reducing the vine, Ellis said.

"It's going to take them a few years for them to settle in," Ellis said.

j.benson@theday.com

UBOX:

More on mile-a-minute vine:

• For photos and information about mile-a-minute vine, visit: www.cipwg.uconn.edu.

• To report mile-a-minute vine, visit: www.cipwg.uconn.edu, send an email to: mileaminute@uconn.edu, or call Ellis at (860) 486-6448.

• A symposium about invasive plants will take place Oct. 25 at UConn in Storrs. Information about the event can be found at: www.cipwg.uconn.edu.