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purple loosestrife (Lythrum salicaria)

Posted in Species Profiles

2013_IPMP summer unsorted 039

Description: Purple loosestrife is a herbaceous perennial with opposite or whorled, lance-shaped, stalkless, leaves. Flowers are magenta and form long spikes. Stems are distinctly square in cross-section.

Habitat: Purple loosestrife thrives in wetlands, poorly drained soils, and areas of standing water.

Invasive Traits: Purple loosestrife has an extended flowering season, June-September, allowing it to produce vast quantities of seed (3-5 million per year). Seeds establish readily in wet habitats for greater recruitment.

Control: Herbicides approved for use in aquatic systems can be used with cut stem of foliar spray methods. Galerucella beetles, which feed on purple loosestrife, have been effective for controlling populations. Hand pulling or cutting can be used for small isolated populations as long as the entire root system is removed and material is bagged and transported off site. Mowing is not recommended as it only contributes to seed dispersal.

Further Reading

Gover, Johnson, Lloyd, & Sellmer 2008

Photo Credits
  1. Cleveland Metroparks
  2. Rob Routledge, Sault College,
  3. Norman E. Rees, USDA Agricultural Research Service – Retired,
  4. Cleveland Metroparks
  5. Cleveland Metroparks