Water hyacinth (eichhornia crassipes), is a free-floating aquatic invasive plant native to South America. It was intentionally introduced to the US in the 1880s via the aquatic gardening industry. It was detected and eradicated from the Black River Bay in Jefferson County, NY in 2015.
Water hyacinth populations grow quickly, in some cases doubling in size within a week. Populations from thick floating mats that impede boating and other aquatic recreation. The mats shade out aquatic vegetation reducing species biodiversity in the ecosystem. The presence of water hyacinth also reduces the amount of open water available for waterfowl and serves as a breeding habitat for mosquitoes.
Water hyacinth has spiked purple flowers with 6 petals one of which has a decorative yellow dot surrounded by shades of purple. Its leaves are green with a glossy appearance and are a curved rounded shape. Leaves are attached to spongy petioles that float on water.
Manual removal is effective for small populations. Larger infestations are better managed using a mechanical harvester or herbicides approved for aquatic use. There are weevils, moths, and planthoppers that are used as biocontrols for water hyacinth, learn more about these options here.
Shaun Winterton, Barry Rice, and Leslie J. Mehrhoff from bugwood.org.