The water hyacinth is a floating plant. This invasive nuisance is planta non grata in much of the world where it often jams rivers and lakes with uncounted thousands of tons of floating plant matter. A healthy acre of water hyacinths can weigh up to 200 tons! In the U.S., water hyacinth is present throughout the southeast, as well as in California and Washington state. In Florida, where for 100 years this weed had the upper-hand in water management, the water hyacinth in most places is under "maintenance control": field crews constantly working to keep the plant numbers at their lowest possible levels, in exchange for the rivers and lakes remaining usable.