Purple Loosestrife


Perennial, upright bushy plant reaching up to 7 feet. Flowers are pink to purple, possessing 5-6 petals and are very numerous on a long spike.


This plant crowds out vegetation required by wildlife for food and shelter. Decreases waterfowl production and wetland/water-shed habitat is eliminated. The loss of productive wetlands would result in reduced hunting and fishing areas. In addition once established frequent clean out of drainage ditches and waterways will become a financial burden.


  • Cultural: Physical removal of the entire plant is required to be effective. When possible all plant parts removed should be dried and burned. All plant parts that remain at any location can resprout.
  • Chemical: Herbicides are effective on small infestations. When treating take care not to damage vegetation around the weed.
  • Biological: Two leaf beetles have been introduced in Eastern Oregon at several locations. Additional releases should be available soon.

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