I am originally from the Amazon River Basin of South America.

It is thought that I arrived in North America in 1884 during the Cotton Exposition in New Orleans, Louisiana. I was taken from this event to other parts of the US because of my flower's beauty.

I have established populations all over North America. You can find me in California, Hawaii, Virginia, North Carolina and Georgia. I am especially problematic in Louisiana, Florida, Alabama and eastern Texas where it is warm most of the year.

I am considered the world's worst aquatic plant. Once I am introduced into an area, I take over very rapidly. In the right conditions I grow incredibly fast. I form very dense mats that clog water ways and make fun water activities like swimming, boating and fishing almost impossible. These mats are also very bad for the ecosystem. Because I am so thick in some areas, the sun cannot penetrate into the water. I block the light to prevent photosynthesis from occurring in the water below me which then an cause oxygen depletion. It is very hard for other species of plants and animals to live where there is not enough oxygen. I reduce diversity in plants and animals also by crushing them, pushing them away, blocking access to the water and eliminating habitat.

The best way to manage me is to keep me from becoming established in the first place. However, it is too late for that in many regions. There are some control methods for areas that I have already taken over. Some of these methods are harvesting, herbicides and biological control agents. One important way to keep me from spreading is to wash and inspect your boats after you use them. Fragments from my former selvescling to your boat and trailer and when you transport us and launch your boat into another body of water we attack.