A water hyacinth is a type of perennial, flowering, aquatic plant native to South America, which has spread with profound speed and distribution throughout much of the world. When not properly controlled, water hyacinths can dominate a body of water and take over a lake or pond so effectively that the water may become oxygen-deprived and no longer able to provide a hospitable environment for fish. A water hyacinth typically has flowers that are purple or lavender in color, and while difficult to get rid of once an infestation has begun, they can potentially be used to eliminate waste in water.
Native to South America, the water hyacinth has spread throughout much of the world, and can be found in regions such as North America, India, Pakistan, and Africa. Though there are several different species, water hyacinths belong to the genus Eichhornia and may also sometimes be referred to as water orchids. They have flat, dark green leaves that are slightly oval or elliptical in shape and the flowers can protrude up to about three feet (almost 1 m) from the surface of the water. Where the water hyacinth has spread, it has often brought with it problems with infestation and choking of waterways.
In the United States (US), there have been numerous issues with the spread of the water hyacinth throughout regions such as Florida. The hyacinths grow so prodigiously that they can completely cover a body of water and choke out all other life that may depend on that water. Mechanical or manual removal of the plants can be difficult and costly, so insect removal has been a common method of dealing with water hyacinth infestation. In the US, weevils that feed on water hyacinths were introduced to areas of hyacinth overpopulation and were fairly effective in cutting down the numbers of plants.
Similar methods have been used in regions such as Africa, and though such infestations are not usually completely eradicated, the problem can be brought under control. In many states in the US, transporting a water hyacinth into the state may be illegal and anyone doing so could face legal prosecution. Despite the potential for overpopulation, there are some potential benefits for which hyacinths can be exploited. For example, the root systems of water hyacinths typically draw microscopic algae and plant life that may provide food for fish, turtles, and aquatic fowl.
Part of the invasive and difficult nature of the water hyacinth is its resilience against harmful chemicals, including metals. This can be used in a beneficial manner, as water hyacinths may be able to help eliminate harmful elements in wastewater facilities. Researchers are also looking into the uses of these hyacinths in cleaning chemical spills and eliminating poisons such as cyanide from bodies of water.