Purple Loosestrife (Lythrum salicaria)
A wetland in Minnesota choked by purple loosestrifeCredit: Minnesota Dept. of Natural Resources
Flowering purple loosestrifeCredit: M.J. Kewley - Great Lakes Indian Fish and Wildlife Comission
Purple loosestrife flower spikeCredit: M. Falck - Great Lakes Indian Fish and Wildlife Comission
How did it get here?
Why is purple loosestrife a problem?
- Arrived in North America as early as the 1800s.
- Settlers brought it for their gardens, and it may also have come when ships used rocks for ballast.
- Purple loosestrife has spread across the 48 United States and Canada, with the exclusion of Texas.
- It is native to Europe and Asia.
What does it look like?
- It is a very hardy perennial and aggressive plant.
- Purple loosestrife invades wetlands and moist soil areas.
- It crowds out native plants.
- It has very little food value for animals.
How do we control purple loosestrife?
- Purple loosestrife can be 4-7 feet tall and have up to 30 flowered spikes.
- Each plant can produce 2.5 million seeds a year.
- Small patches can be dug up by hand and then dried and burned.
- Herbicides can be used, but they will affect other plants and possibly kill some of the good plants.
- Galerucella beetles feed only on purple loosestrife, these beetles can be released on the plants, but this can take a long time to bring an infestation under control.