Kurt St, Max-Planck Institute for Plant breeding Research, Bugwood.org

Family: Pontederiaceae (Pickerelweed Family)

Synonym(s): Pontederia azurea

Duration: Perennial

Habit: Herb

Listed by:
Invasive Plant Atlas of the US: 1
Federal Noxious Weed: 1
TDA Noxious Weed: 1
TPWD Prohibited Exotic Species: 1

Description: As the common name suggests, this plant is a rooted water hyacinth that has both submerged and emergent leaves. Flower stalks will appear above water with showy purplish-blue flowers with a varying 7-50 flowers per stalk. Flower margins are fringed.
Can be confused with the widespread invasive Water hyacinth (Eichhornia crassipes) but is distinguished by its fan-like submersed leaves and long floating stems with large rounded leaves, slender petioles and secondary submerged roots. Also, the fact E. azurea remains anchored to the substrate it is confined to shallow ponds and the edges of lakes and rivers

History: Introduced as an ornamental in the United States in mid-1880s.

Biology & Spread: Spreads easily by plant fragments hitchhiking on boating and other equipment, and in return it forms dense, impenetrable mats which clog waterways, making it impossible for boating, fishing and other water activities.

Ecological Threat: E. azurea reduces biodiversity by crowding out native aquatic plants, degrades water quality by blocking the air-water interface which greatly reduces oxygen levels for underwater animals like fish.

While a few populations have been documented and eradicated in Florida and Texas and a few may still remain, it is not known to be a widespread problem in North America. However, due to its potential invasiveness it is listed as a Federal Noxious Weed.

US Habitat: It thrives in slow moving waters from rivers, marsh lands, and lakes.

Distribution

US Nativity: Introduced to U.S.

Native Origin: Central America, the Caribbean, and regions of South America

US States: PR (established)

Resembles/Alternatives:

Management: Chemical- Aquatic-safe herbicide will be necessary and do not apply during the flowering periods.
It is likely that it can be treated similar to E. crassipes (water hyacinth) which can use foliar application of diquat dibromide (1-2 quarts/acre smaller plants, up to 3 qt/ac for mature plants). Frequent applications may be required.

USE PESTICIDES WISELY: ALWAYS READ THE ENTIRE PESTICIDE LABEL CAREFULLY, FOLLOW ALL MIXING AND APPLICATION INSTRUCTIONS AND WEAR ALL RECOMMENDED PERSONAL PROTECTIVE GEAR AND CLOTHING. CONTACT YOUR STATE DEPARTMENT OF AGRICULTURE FOR ANY ADDITIONAL PESTICIDE USE REQUIREMENTS, RESTRICTIONS OR RECOMMENDATIONS. MENTION OF PESTICIDE PRODUCTS ON THIS WEB SITE DOES NOT CONSTITUTE ENDORSEMENT OF ANY MATERIAL.

Listing Source

Texas Department ofAgriculture Noxious Plant List
Texas Parks and Wildlife Department Prohibited Exotic Species
Invaders Program
Federal Noxious Weed
Union of Concerned Scientists
United States Forest Service Southern Research Station

Text References

Barrett, S.C. 1978. Floral biology of Eichhornia azurea (Swartz) Kunth (Pontederiaceae). Aquatic Botany 5:217-228.

Romero-Gonzalez G.A., G.C. Fernandez-Concha, R.L. Dressler, L.K. Magrath and G.W. Argus. 2008. Fora of North America: Eichhornia azurea (Swartz) Kunth, Eichhornia. 4. 1842. Accessed 21 Novemeber 2008: http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=220004607

https://plants.ifas.ufl.edu/plant-directory/eichhornia-azurea/

Data Source

Last Updated: 2024-01-24 by ARMO