Eichhornia crassipes

Eichhornia_crassipes_ by By Wouter Hagens
Photo: Wouter Hagens

Synonyms: Eichhornia speciosa, Heteranthera formosa, Piaropus crassipes, Pontederia crassipes

Common names: water hyacinth

Eichhornia crassipes (water hyacinth) is a floating freshwater perennial (family Pontederiaceae) that jams rivers and lakes with tons of floating plant matter. Floating mats of this plant can weigh up to 200 tons per acre. In California, Eichhornia crassipes typically is found below 660 feet (200 m) elevation in the Central Valley, San Francisco Bay Area, and south coast.

Cal-IPC Rating: High

Cal-IPC Assessment

Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.

Weed Management Notes

  • Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

Other Eichhornia crassipes Information

  • CalPhotos - Images of plants taken mostly in California.
  • Calflora - See the distribution of this species on Calflora's map of California.
  • CalWeedMapper - Distribution information with ability to determine regional priorities.
  • Jepson Online Interchange for California Flora - Information on taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
  • USDA PLANTS Database - Federal database with information on identification and distribution, and links to websites in individual states.
  • Bugwood - National database from the Center for Invasive Species and Ecosystem Health at the University of Georgia.
  • EDDMapS - North American distribution based on Early Detection and Distribution Mapping System.
  • Additional photos

    Eichhornia crassipes_water hyacinth_Bob Case_cropped
    Eichhornia crassipes, water hyacinth, infestation. Photo: Bob Case