Purple loosestrife

Tracking purple loosestrife and it's biocontrol beetles

Purple loosestrife, Lythrum salicaria, is a species on the Minnesota Noxious Weed Control and on the DNR's Prohibited Invasive Species list. It's commonly found in wetlands. along shorelines and in roadside ditches. Biocontrol efforts using Galerucella beetles have been highly successful in Minnesota in controlling purple loosestrife populations, but changes in both purple loosestrife and Galerucella beetle populations have left density and distribution maps outdated. To learn about purple loosestrife biocontrol success visit the DNR's webpage.

Photo by Leslie J. Mehrhoff, University of Connecticut, Bugwood.org

You can help!

Continuous management is critical to purple loosestrife control. You can help land managers and researchers understand purple loosestrife and Galerucella beetle distribution and density so beetles can be reared and released to effectively manage purple loosestrife. Your help is needed with one or more of these volunteer opportunities:

Photo by Rob Routledge, Sault College, Bugwood.org

Purple loosestrife identification

Purple loosestrife is a perennial wet-loving herbaceous plant with conspicuous purple-pink, spiked flowers that bloom much of the summer.  Multiple rings of flowers bloom from the bottom of the spike to the top. Flowers typically have six petals. Purple loosestrife can grow 3-7 feet tall with multiple stems from a single rootstock. Stems are stiff and typically square, but can have up to six sides. Leaves are opposite or whorled, lance shaped with smooth edges and can be downy. To learn more about purple loosestrife identification visit this DNR webpage. To learn about native look-alikes of purple loosestrife visit this University of Wisconsin factsheet

Above photo from Steve Dewey, Utah State University, Bugwood.org

Galerucella beetle identification

There are two common loosestrife beetles in Minnesota, Galerucella calmariensis and G. pusilla. For this project we are not asking you to identify these beetles to species, rather just to genus, Garleculla. Adult beetles of both species are about 5 mm long and orange to gold colored with varying degrees of dark stripping on their hard outer wings. The above beetle has very clear black strips. Immature larvae are translucent greenish-yellow when young and mature to a bright yellow up to 5 mm long with a black head and black spots or shields along their body. To learn more about Galerucella identification visit this UMN Extension webpage

Above photos: adult G. calmariensis beetle by Mark Schwarzlander, University of Idaho and larvae G. pusilla photo by Eric Coombs, Oregon Department of Agriculture both from Bugwood.org

Reporting 

Reporting is a bit complicated for this project, but we know you're smart and can do it! Remember, you don't need to do all aspects of this project. Feel free to pick one or two to learn and grow your skills and help resource managers understand this complicated but important information.

Galerucella beetle reports in iNaturalist

We picked reporting to iNaturalist instead of EDDMapS because iNat can help you with identification, and insect identification can be tricky. Professionals can easilier track reports in both platforms.

Watch this 1:25 minute video about how to report in iNaturalist. 

Purple loosestrife reports in EDDMapS Pro

EDDMapS Pro uses the same robust EDDMapS platform but allows revisists which are critical for this project. However some upfront work is requred for reporting success.

EDDMapS Pro work before going to the field

For purple loosestrife we hope to update reports in EDDMapS through EDDMapS Pro revisits. We are most interested in sites with 1 acre or greater than 1000 purple loosestrife plants because these can sustain Galerucella  biocontrol. 

Using EDDMapS Pro requires some pre-work at home or office:

EDDMapS Pro on your phone

Once this home or office pre-work is done, on your phone:

After the first time, this isn't hard. But for more information watch the above 5:09 left  video and visit this EDDMapS Pro walk-Through

Now you're ready to head to the field.

All questions about this project should be directed to Angela Gupta, UMN Extension Forester, agutpa@umn.edu