Beetles to help eradicate purple loosestrife
 

TORRINGTON — Late this month, thousands of beetles will hatch in a swampy area of Burrville, along Winsted Road, and they'll be hungry.

That's just what Donna Ellis wanted.

Ellis, who is the extension educator for the University of Connecticut's Department of Plant Science, offered her help when planners for the Sue Grossman Still River Greenway in that swampy area worried about an invasion of purple loosestrife that had overwhelmed the river's native vegetation.

Beetles have been released in seven other communities in the region — including Kent, Litchfield, New Hartford, Salisbury, Southbury, Washington and Winsted — to control purple loosestrife through UConn's program.

Ellis coordinates a program that teaches volunteers how to become beetle farmers and gives them Galerucella beetles to raise.

Ted Barlow and Fran Schaller, members of a greenway committee, signed up for the program and were educated about the beetles that are roughly one-fifth of an inch in size, and about the plant whose stems end with a spike of many individual flowers with pink-purple petals.

Both the insects and the plant are native to Europe and got here when European settlers came several centuries ago.

Barlow and Schaller learned they could raise a small group of beetles — in their case, about 50 — in a roughly 5 gallon pot with a mosquito netlike mesh cover that kept them from flying away in Barlow's backyard.

Those beetles mated and multiplied over a six-week period, starting in the spring of 2004, into roughly 4,200 beetles that were released that summer into a targeted wetland area along the greenway's path.

Late this month thousands of those beetles' descendants, roughly 6,000 of them, will emerge from their wintering sites in plant litter and start munching away on the purple loosestrife as they have for four previous springs.

The leaf-feeding beetles reduce the growth and reproduction of the weed, but they won't eliminate it. Adult beetles feed on purple loosestrife's leaves and lay their eggs. When the eggs hatch, the larvae feed on the leaves and stems as they move into the soil. The larvae cause the most damage to the plant and reduce the number of seeds produced.

Biological control — the use of natural to reduce a plant's population below an economic or biological threshold — is considered a sustainable, low-input method to control purple loosestrife, said Ellis. Her program focuses specifically on the use of the beetles to accomplish this.

Ellis has been keeping track of the impact the beetles in Torrington are having on the weeds here and says they are making good progress, though she will have a better picture in a few years.

"We're certainly under way in Torrington. They are getting established," she said. "They are purple loosestrife eating machines."

Between 1996 and 2007, more than 1.4 million beetles were introduced to about 100 wetland areas across Connecticut through the UConn program. More than 600 people have been trained as beetle farmers.

The beetles, whose predators include birds, are widely established in more than 30 states and eight provinces where the weed is a problem. In areas where the insects are more established, people have reported a gradual increase in native vegetation.

"We can't eradicate purple loosestrife, but we can manage it with the beetles," said Barlow.

News article  published by American Republican Incorporated on April 22, 2008.  Reprinted with permission.

 

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