European purple loosestrife is invading North America wetlands, shorelines, roadside ditches, and moist areas. Thick stands of purple loosestrife can crowd out native plants, and when desirable native plants are excluded, so are many insects, birds, and other wildlife that evolved in the native ecosystem.

You should know how to identify purple loosestrife so you can help prevent its spread. Each perennial plant grows from a root crown which can produce over 2 million seeds per year when mature. The stems have distinct ridges and they often feel nearly square. Purple loosestrife produces dozens of pinkish purple mid-summer flowers at the top of each stem and its leaves are smooth-margined, often growing in whorls around the stem. Plant height ranges from 3' to 7'.

WHAT YOU CAN DO

Learn to identify purple loosestrife - never transplant it. After walking in loosestrife infested areas, be sure to thoroughly clean seeds from your clothing and muddy footwear. Advoid any seed mixure labeled with purple loosestrife. To report small new infestations (less than 100 plants) or for more information call the Minnesota DNR in St. Paul 651.296.2835 or Minnesota Sea Grant in Duluth 218.726.8712.