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Center for Aquatic and Invasive Plants Logo    Plant Management in Florida Waters

Center for Aquatic and Invasive Plants Logo    Plant Management in Florida Waters

Quick Facts

  • Scientific name: Pistia stratiotes
  • Origin: South America
  • Introduction:Colonial period, ship ballast (?)
  • Aquatic community: Floating
  • Habitat: Water surfaces
  • Distribution: Peninsula, rare in panhandle
  • Management effort: Maintenance control
  • 2017 public waters / plant acres: 147 (32%) / 1,999
  • 2017 Waters / acres controlled: Water lettuce 27 / 344. Lettuce / hyacinth mix 153 / 24,297.

Water lettuceWater lettuce


Environmental and Economic Concerns

  • Growth rate similar to water hyacinth – can double in a few weeks
  • Reproduce by seeds and stolons
  • Harbors mosquitoes
  • Dense mats prevent air and light diffusion into water, consume oxygen
    • displacing native plants, fish and wildlife
    • preventing decomposition of detritus
  • Increases sedimentation by shedding roots, leaves and shoots
  • Rapid dispersal by wind and water movement
  • Mats jam against bridges and reduce water flow at flood control structures
  • Reduces property values and local tax revenues

Management Options

  • Biological: 2 host-specific insects (ineffective to date)
  • Chemical: Diquat, flumioxazin; carfentrazone Occasionally copper near drinking water intakes
  • Mechanical: Harvest around bridges and flood control structures
  • Physical: Occasional winter drawdowns (drying and desiccation)

Florida Fish & Wildlife Conservation Commission, Status of the Aquatic Plant Maintenance Program in Florida Public Waters, Annual Report – Fiscal Year 2016-2017.