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Home / Aquatic Invasives / Aquatic Plants / Water Lettuce

Water Lettuce

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Water lettuce
Water lettuce, plants - Photo by Troy Evans; Great Smoky Mountains National Park
Scientific Name: 

Pistia stratiotes L. Royle (ITIS)

Common Name: 

Water lettuce, tropical duckweed

Native To: 

Unknown, possibly South America, Africa, or the U.S. (Dray et al. 1988)

Date of U.S. Introduction: 

First described in Florida in 1765; experts disagree as to whether water lettuce is native to the U.S. (Ramey 2001)

Means of Introduction: 

Unknown (possibly native to the U.S., or it may have arrived in ballast water) (Ramey 2001)

Impact: 

Grows into dense mats that clog waterways (Ramey 2001)

Current U.S. Distribution: 
Southern U.S., Eastern U.S.

Distribution / Maps / Survey Status

University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.
DOI. USGS. Wetland and Aquatic Research Center.
Provides detailed collection information as well as animated map.

Images

University of Georgia. Center for Invasive Species and Ecosystem Health.

Videos

Google. YouTube; University of Florida. IFAS. Center for Aquatic and Invasive Plants.

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Water Lettuce.

Partnership
European and Mediterranean Plant Protection Organization.
IUCN. Species Survival Commission. Invasive Species Specialist Group.

Ontario's Invading Species Awareness Program (Canada).

University of Georgia. Center for Invasive Species and Ecosystem Health.
East African Network for Taxonomy.
USDA. FS. Institute of Pacific Islands Forestry.

Texas Commission on Environmental Quality, Galveston Bay Estuary Program; Houston Advanced Research Center (HARC).

Centre for Invasive Species Solutions; Atlas of Living Australia; Australian Government. Department of Agriculture, Water and the Environment.

Federal Government
DOI. USGS. Wetland and Aquatic Research Center.
Provides distribution maps and collection information (State and County).
USDA. NRCS. National Plant Data Center.

USDA. ARS. National Genetic Resources Program. GRIN-Global.

International Government
New South Wales Department of Primary Industries (Australia).
State and Local Government

Pennsylvania Department of Conservation and Natural Resources.

See also: Invasive Plant Fact Sheets for plant species (trees, shrubs, vines, herbs and aquatic plants) that have impacted the state's natural lands

Wisconsin Department of Natural Resources.

Florida Fish and Wildlife Conservation Commission.
Academic
Texas A&M University. AgriLife Extension Service. Department of Wildlife and Fisheries Sciences.

University of California. Agriculture and Natural Resources. California Aquatic Invasive Species.

University of Florida. IFAS. Center for Aquatic and Invasive Plants.

Citations