Pond Projects - Purple Loosestrife

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Background:  Purple Loostrife, Lythrum salicaria L., 

 is an exotic perennial plant of European origin that is invading and degrading wetland habitats all across North America. This invasive plant can form dense monotypic stands in a variety of wetland and lakeshore habitats replacing native plant species, thus degrading  food, shelter and nesting sites for wildlife. Currently there are no chemical or mechanical methods that provide long-term control of established stands of purple loosestrife. However, biological control, the use of natural enemies to control a pest, shows real promise. Since 1992, a nationally coordinated program has introduced two leaf-feeding species of European beetles in North America.

Our Objective: Permanent reduction of the loosestrife   infestation by as much as 90%, ( total eradication is not possible).  Ultimately, the goal is a natural balance of  . loosestrife (food for beetles) and beetle population (predators who feed exclusively on loosestrife).

Project start date:   May 2001 - 10,000 beetles (galerucella pusilla )  acquired from the US Department of Agriculture were released near dense stands of  purple loosestrife. These beetles are known to be highly specific predators of p. loosestrife leaves and flowers.