Galerucella Leaf Beetle Survey - Oregon Dept. of Agr...

Purple loosetrife (Lythrum salicaria) is an invasive weed in the United States that outcompetes native plants along waterways, streams and reducing habitat and refuge sites for many animals. In 1992, the Oregon Department of Agriculture began released Galerucella beetles into sites around the state, in order to control purple loosetrife outbreaks. These beetles feed on the plants leaves and the new shoots, limiting it's ability to grow and reproduce. In many sites around Oregon, this management strategy have proven to be very effective in reducing purple loosestrife and protecting native plants and wildlife, where mechanical removal and chemical herbicides would have been ineffective, impossible or harmful to the environment.

Recently, residents around the Oaks Bottom Wildlife refuge in Sellwood, OR have begun seeing high numbers of the small tan beetles around their homes where they have not seen them before. The higher populations are believed to be a result of the the long periods of higher temperatures and reduced rainfall that Oregon has been experiencing this summer.

Large population booms of insects released as biological control agents are very unlikely but do occur occasionally. Since the release of Galerucella over two decades ago in Oregon, there have not been population increases such as this observed, and we don't expect this to last. However, with your help, we can try to understand how large the population is currently, how widespread the beetles are outside of release areas, and what other plants the beetles are feeding on. Thank you for your help and participation in this project, and helping to protect Oregon against invasive pests!

For more information about Weed Biological Control in Oregon:

http://www.oregon.gov/ODA/programs/Weeds/Pages/BiologicalControl.aspx

Contact Us

Phone: 503-986-4550
Email: info@oda.state.or.us