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Leaf-eating beetle rids Michigan wetland of purple loosestrife

Exotic and invasive purple loosestrife used to dominate the I-696 wetland mitigation site in Southfield, Michigan. Not anymore. The Michigan Department of Transportation (MDOT) restored choked-out native vegetation using the Galerucella beetle as a bio-control agent. The beetle only feeds on purple loostrife and has been approved by the U.S. Department of Agriculture as a safe and effective way of controlling the pesky plant. To capture the beetles, MDOT staff simply tapped the loosestrife plants with their fingers and let the beetles fall into a container. About 500 beetles were released at the Southfield site in 2005, 1000 in 2006, and 1400 in 2007. More than 99% of the site's purple loostrife was eradicated, and the beetles' work spurred the growth of switch grass, water plantain, monkey flower, and other native wetland plants. Deer, songbirds, and small mammals now thrive on the once-inhospitable landscape. As for the beetles...they devour any new loosestrife growth and leave their tattered hosts for "fresh" stands elsewhere.
--Mar 23, 2009

Donald Sneed, (517) 335-2944 or

This photo shows a beetle perched on a purple loosestrife leaf. The beetle is eatingand effectively destroyingthe invasive plant.
Photo by Photo by MDOT.
Beetles loosed on the purple loosestrife covering this wetland successfully destroyed the invasive plant.

On Wetlands and Uplands - Michigan
Updated: 12/12/2012
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