Bare Hill Pond may have its weeds, but the Nashua River, ponds, and wetlands across the state are being threatened—as they have been since the 19th century—by purple loostrife. The plant, which is native to Europe and Asia, was brought to America sometime during the 1800s as an ornamental garden plant. However, with no natural enemies in this country, it has taken a chokehold in the wet areas where it thrives, crowding out native species and destroying ecosystems in the process. Fortunately, biologists think they may have found a way to control it—with another alien species, the Galerucella beetle. Research projects involving the beetles are being undertaken all over the state, the closest one along the Nashua River. The local project, managed by the Nashua River Watershed Association, has about 25 volunteers—including Under Pin Hill Road resident Claudia Jarratt—raising the little loostrife-eaters for release at targeted sites along the river.

“Biocontrol is one of those things that raises everyone’s eyebrows,” Jarratt said in a recent interview. “Kudzu was brought to this country to be a controller, and we all know what happened with that.”

The Galerucella beetle. (Courtesy photo)

However, rigorous testing undertaken by the International Institute of Biological Control, the USDA Agricultural Research Service, and the U.S. Fish and Wildlife Service concluded that introduction of the Galerucella beetle into wildlife habitats would have no significant impact. The testing began in 1986 in Europe, and included laboratory studies that showed the beetles fed on few other plants, even if given no other choice. Field testing showed “occasional spillover feeding” on nontarget plants, but with no significant damage. In 1992 the USDA approved the importation of two varieties of Galerucella beetles for the control of purple loostrife.

People who admire the plant for the color it adds to the late-August landscape need not fear that the days of purple loostrife are numbered. According to Jarratt, use of the beetles will not eradicate loostrife, but will allow it to coexist with native plants, helping to restore the ecosystem. The plant is pushed back enough that native species can poke through and become reestablished.

“This has huge implications for native wildlife,” said Jarratt.

The Massachusetts Wetlands Restoration Program (WRP) started a pilot loostrife biocontrol project in Walpole in 2000. Now there are 17 active projects in towns from Eastern to Central Mass., including one at Bolton Flats and one on the Nashua River Rail Trail in Groton, both started in 2006.

Jarratt said she read about the Groton project, “Teaming with Beetles,” in a newspaper article, which said that volunteers were needed to help raise the beetles. With her background in biology and a love of nature, the project piqued her interest.

“I thought, ‘I raised a big family—beetles would be easy,’” she said.

Jarratt attended a three-hour training session, where potential volunteers learned about the problems created by purple loostrife, and the beneficial impact of the beetles. The goal for the volunteers was to inoculate “sleeves” of loostrife with 10 beetles, and grow the population to about 100 before turning them over to project managers for release at targeted sites.

Jarratt said that in early May she was given a clump of purple loostrife, which she had to keep in standing water until the plant grew to be about 10 inches tall. She used a tomato cage to prop it up, and kept it covered, as instructed, with a provided containment sleeve. When the plant reached the desired height, she notified the project office at the NRWA, and then went to pick up her starter beetles. She released them into the plant, which was to remain in standing water until the beetles were ready for release. Jarratt noted that it takes five to six weeks for the test beetle population to grow to 100. The cycle, she said, is yearly, so once the beetles have been turned over for release, volunteers are done until the next year.

“It’s not a huge commitment,” she said.

A passionate naturalist whose property has been certified as a nature preserve, Jarratt is excited about the project. She said that the use of volunteers helps make the project cost-effective. Help is needed, she said, not only in raising beetles, but also in monitoring them after their release, identifying new target sites, participating on a supervised team to dig source plants and pot them to project standards, in fundraising and education, and more. She said she would like to see more volunteers recruited from Harvard, and invites anyone interested to e-mail her at pinhill@charter.net.

For more information about NRWA’s Teaming with Beetles project, e-mail Rick Muehlke, land programs and outreach assistant, at RickM@nashuariverwatershed.org.