Water Hyacinth

Eichhornia crassipes (Mart.) Solms

Common Name: water-hyacinth, common water-hyacinth, floating water-hyacinth

Taxonomy: Division-Magnoliophyta (Angiosperms); Class-Liliopsida (Monocots); Subclass-Liliidae; Order-Liliales; Family-Pontederiaceae (Pickerelweed Family); Genus-Eichhornia.

Description: Floating plants with thick, glossy leaves, inflated petioles and spikes of lavender flowers.

Native Range: Brazil, South America.

The Water Hyacinth is a destructive aquatic weed also know as:

The “Beautiful Blue Devil,”
A Pariah,
A Menace to Commerce, and
A Plague.

Grows into dense impenetrable mats in fresh water:

May extend bank-to-bank,
Prevents transport of even large motorized boats,
Disrupts commercial fishing,
Damages infrastructure, water supply pump stations, and other facilities,
Reduces bio-diversity, and
Damages Boats.
Threatens Socio-economic Structure, Food Supply and Health
Florida and Other States Spend Millions to Control the Plants
Disrupts millions of people’s lives

People have starved in Third World Countries:

Threatens provision of fresh water
Prevents access to gardens, hunting areas, fishing areas, or market places
Due to reduced nutrition, degraded water, increased disease, and degraded environment
Lowers the available food sources for people

Survivability of the Plant:

Propagates in three ways:

Any cutting from the plant takes root and grows
Shoots a “runner” and begins a new plant
Self-pollinates if insects do not

Seeds may number as many as 45 million per acre and can lay dormant for 15 years.

Easily adapts to terrestrial environments and now adapting to colder and colder climates

Fully grown in 6 weeks and doubles area of coverage every five days when mature.

States where Water Hyacinth is reported as invasive*: CA, DE, FL, GA, LA, TX

Three Means of Eradication and Control:

Chemical Controls are Ineffective:

temporary
counter productive
does more harm than good (Kills, native plants and fish, and poisons water.)

Biological Controls are Ineffective

Imported insects become uncontrollable
Insects may cause other problems
Other means must be used to eradicate and control the insects

Mechanical Harvesting is good and bad

Good: areas that are repeatedly cleared slow the growth of the plant as it becomes “tame”
Bad: creates large amounts of bio-waste material

Range indicates presence in at least one site within a drainage (USGS Hydrologic Unit 8), but does not necessarily imply occurrence throughout.

Nonindigenous Occurrences: Established and self sustaining in over 150 U.S. drainage basins in 10 states. Recently found persisting as far north as the Lower Chesapeake [P. Baldwin s.n. (WILLI)] and Tidewater regions of coastal Virginia (pers. comm. L. Swanson, VA Coop. Ext. Agency). Weedy in North Carolina north and inland to the Upper Tar and Neuse River drainages (pers. comm. Stratford Kay, NC State Univ.). Intermittently distributed in Georgia and Mississippi. Often extemely problematic in Florida, Alabama, Louisiana and eastern Texas. Also established in California and Hawaii.

Waif or nonpermanent populations have been reported from more temperate states including New Jersey, Kentucky, Tennessee, Missouri and Arkansas where plants apparently escape summertime cultivation to grow as annuals, but do not persist vegetatively through the winter. Water-hyacinth is stocked annually in private fish ponds throughout southern Arizona and in Delaware at old mill ponds. It has been reported from the Great Cypress Swamp, southern Delaware and from isolated, natural locals in New Jersey. Water-hyacinth is capable of reproducing by seed. However, it is not known if recurrence by seed plays a role in the waif populations of these temperate states. October 2002 First recorded for the state of Illinois in the Fox River Chain O' Lakes in the Upper Fox drainage where several hundred plants were documented, although none are expected to overwinter (Marencik s.n. FLAS; pers. comm. J. Marencik, Lake Co. Health Dept, CNC). December 2002 Reported for Maryland in 1998 at a pond near Lake Shore, in the Severn Drainage; this site will be checked during the 2003 growing season to see if the plants have persisited (pers. comm. W. Sipple, EPA). October 2003 Several plants were reported from the Ebbing Air National Guard Base in Fort Smith, Arkansas, where plants were found growing along a drainage ditch located just below a spillway for a small, recreational, fish stocked pond. All of the plants were manually removed and the site will be monitored for future occurrences (pers. comm. S. Hardcastle and J. Christensen, AR Air National Guard).

Author: C.C. Jacono and M.M. Richerson

Revision Date: 22 Oct. 2003

This page was prepared by the Center for Aquatic Resource Studies. The Center is part of the Biological Resources Division of the Geological Survey within the U. S. Department of the Interior

•US States/Countries Spend Millions to Control the Plants –
Florida	$40,000,000.00/yr
Louisiana
Mississippi
Georgia
Alabama
Texas
California
South Carolina