Page Banner

United States Department of Agriculture

Agricultural Research Service

Title: Waterhyacinth

Authors
item Center, Ted
item Hill, Martin - PPRI, SOUTH AFRICA
item Cordo, Hugo - US EMBASSY ARGENTINA
item Julien, M - CSIRO, AUSTRALIA

Submitted to: Biological Control of Weeds in the United States
Publication Type: Book / Chapter
Publication Acceptance Date: October 1, 2002
Publication Date: December 11, 2002
Citation: Center, T.D., Hill, M.P., Cordo, H., Julien, M. 2002. WATERHYACINTH. Biological Control of Weeds in the United States. 41-64 (Book Chapter) 2002.

Interpretive Summary: This book chapter provides an overview of the biology, invasive ecology and associated problems, and biological control of the floating aquatic weed waterhyacinth in North America. Dense waterhyacinth mats create impenetrable barriers that obstruct navigation. Floating mats block drainage, cause flooding, and prevent subsidence of floodwaters. Large rafts can cause bridges to collapse. Waterhyacinth hinders irrigation by impeding water flow, clogging irrigation pumps, and interfering with weirs. Infestations can render multimillion-dollar flood control and water supply projects useless. Infestations block access to recreational areas, decrease waterfront property values, and harm the economies of communities dependent upon water-related activities. Shifting mats prevent boats from reaching shore, exposing marooned occupants to environmental hazards. Waterhyacinth infestations intensify mosquito problems by hindering insecticide application, interfering with predators, increasing habitat for attached species, and impeding runoff and water circulation. Dense mats reduce light to submerged plants, thus depriving aquatic communities of oxygen. The resultant lack of phytoplankton depresses invertebrate communities, ultimately affecting fisheries. Drifting mats scour vegetation and destroy native plants. Waterhyacinth also competes with other plants, often displacing wildlife forage and habitat. Higher sediment loading from siltation and increased detrital production occurs under mats. Herbicidal treatment or mechanical harvesting of waterhyacinth often damages nearby desirable vegetation. Three biological control agents have been introduced which have partially alleviated many of these problems.

Technical Abstract: This book chapter provides an overview of the biology, invasive ecology and associated problems, and biological control of the floating aquatic weed waterhyacinth in North America. Dense waterhyacinth mats create impenetrable barriers that obstruct navigation. Floating mats block drainage, cause flooding, and prevent subsidence of floodwaters. Large rafts can cause bridges to collapse. Waterhyacinth hinders irrigation by impeding water flow, clogging irrigation pumps, and interfering with weirs. Infestations can render multimillion-dollar flood control and water supply projects useless. Infestations block access to recreational areas, decrease waterfront property values, and harm the economies of communities dependent upon water-related activities. Shifting mats prevent boats from reaching shore, exposing marooned occupants to environmental hazards. Waterhyacinth infestations intensify mosquito problems by hindering insecticide application, interfering with predators, increasing habitat for attached species, and impeding runoff and water circulation. Dense mats reduce light to submerged plants, thus depriving aquatic communities of oxygen. The resultant lack of phytoplankton depresses invertebrate communities, ultimately affecting fisheries. Drifting mats scour vegetation and destroy native plants. Waterhyacinth also competes with other plants, often displacing wildlife forage and habitat. Higher sediment loading from siltation and increased detrital production occurs under mats. Herbicidal treatment or mechanical harvesting of waterhyacinth often damages nearby desirable vegetation. Three biological control agents have been introduced which have partially alleviated many of these problems.

Last Modified: 8/19/2014
Footer Content Back to Top of Page