Stewardship Overview: Monitor natural areas for the presence of L. salicaria. Maintain preserves so that purple loosestrife cannot invade and flourish. For small infestations, eradication is possible with spot applications of glyphosate herbicides. Monitor the containment and control procedures.
Current methods for eradicating large, dense populations of loosestrife are not totally effective. Mechanical contol methods are ineffective, and the herbicide most effective is non-selective. Realistically, the long-term control of large populations may require biological controls and/or better herbicides, but their development is at least several years away. Therefore, containment and minimizing seed production are the present contol objectives for large dense populations. (MN DNR 1987)