Water hyacinth (eichhornia crassipes), is a free floating aquatic invasive plant native to South America. It was intentially introduced to the US in the 1880’s via the aquatic gardening industry. It was detected and erradicated 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 form thick floating mats that impede boating and other aquatic recreation. The mats shade out aquaic vegetation reducding species biodiversity in the ecosystem. The presence of water hyacinth also reduce the amount of open water available for waterfowl and serves as a breeding habitiat 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 apperance and are a curved rounded shape. Leaves are attached to spongy petiols that float on water.
Manual removal is effective for small populations. Larger infestations are better managed using a mechanical harvestor or herbicides approved for aquatic use. There are weevils, moths and plant hoppers 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.