Purple Loosestrife—Lythrum salicaria

An attractive but invasive perennial, purple loosestrife has become established in a wide range of habitats including river banks, lake and pond shores, irrigation ditches and roadsides.

purple loosestrife plant
Plants grow in clumps. Mature plants can have 30 to 50 stems growing from a single rootstock. Flowers are showy and vibrant.

purple loosestrife flowers
Multiple flowers occur on 4 to 10 foot spikes, with pink-purple petals and yellow centers. Each plant produces one to three million seeds, which remain viable for several years.

purple loosestrife infestation
Purple loosestrife invades many wetland types where it crowds out native plants and degrades wetland habitat.

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Identification and Control Information

[Photos, left to right: Joseph M. DiTomaso, University of California - Davis, Bugwood.org; John D. Byrd, Mississippi State University, Bugwood.org; Agriculture and Agri-Food Canada Archive, Agriculture and Agri-Food Canada, Bugwood.org]