Purple Loosestrife State-wide ProgramMissouri Department of Conservation Invasive Plant Workshop Powder Valley CA Kirkwood , Missouri May 16, 2012 Kyle Lairmore Private Land Conservationist Missouri Department of Conservation
What is Purple Loosestrife ? (Lythrum salicaria) •Native of Europe, Asia and portions of Africa and Australia •Introduced in the US as a landscaping plant due to its showy purple blooms •Invasive to wetlands throughout the mid-western and northeastern United States. •Produces 1-50 stems per plant with a height ranging from 3-7 feet tall •One plant can produce as much as 2.5 million seeds annually which can remain viable in the soil for many years. •It often outcompetes native vegetation and eventually creates a monoculture which affects the natural community
Purple Loosestrife Distribution
Current Purple Loosestrife Program Program created in the late 1980’s 4-6 hourly employees hired each summer (June-July)Control Methods: Chemical Biological
Chemical Control Important to choose correct aquatic approved herbicide and follow label directions Proper application technique and safety precautions Sponge, spray, etc Protective clothing, etc. Herbicide – Rodeo + Surfactant
Biological Control Involves the release of a specific species to restrict the spread of the invasive. Introductions must be carefully studied and monitored so as to not cause another problem Examples include: Foliage eating beetles (Galerucella spp.) and root-boring weevils (Hylobius spp.) for Purple loosetrife
Comparison of Various Herbicides to Improve Effectiveness of Purple Loosestrife ControlMDC Project Leader: Kyle Lairmore (MDCPLS)Principal Investigator: Doreen Mengel (MDCRS) & Kyle Lairmore (MDC PLS)Team members: Ivan Vining, BrentVandeloecht, Ted Seiler, Bill White, BobDeWitt & John Knudsen (ALL MDC)
Study NeedLooking at alternative herbicides thatwill have a residual effect on the plantas well as prevent successfulgermination by seeds in the soilReduce staff time and funding towardsprogram (long term)Residual effect on purple loosestrifewith minimal effect on non-target plantspecies
Management Prediction or Objective Determine which treatment provides the most effective long-term population control of purple loosestrife. Determine the effect of each treatment on the native plant community.
Uncertainties/Risk Tolerance Is there an herbicide labeled for aquatic settings that provides long-term control of purple loosestrife? What are the risks of not treating purple loosestrife annually? What are the effects on the native plant community?
Evaluation of Success A herbicide will be considered successful if it meets the objectives of the study; it shows a long-term effect on purple loosestrife while having minimal if no effect on native plant community and re-vegetation of desirable plant species A herbicide would not be selected if it shows no long-term effects on purple loosestrife and allows no re-vegetation of native and/or desirable plant species
Summary Purple Loosestrife continues to be an issue in wetlands, competing with native plants while not providing any benefits to wildlife We have an active state-wide eradication program We hope the research project will help us find alternative herbicides which will be more effective for eradicating Purple Loosestrife
Questions? Kyle LairmoreMissouri Department of Conservation 573-437-3478 *112 Kyle.Lairmore@mdc.mo.gov