Water hyacinth can be found in both natural and man-made freshwater systems (ponds, sloughs, rivers). It will not tolerate brackish or saline water with salinity levels above 1.8 percent (Penfound and Earle 1948). In California water hyacinth typically is found below 660 feet (200 m) elevation in the Central Valley, San Francisco Bay Area, and South Coast. The Sacramento-San Joaquin Delta and several of the rivers drained by this delta are heavily infested.
The Water Hyacinth in Bloom!
Water Hyacinth is an attractive floating aquatic plant with shiny green leaves and delicate lavender flowers. It was introduced into the Delta from South America more than 100 years ago. This extremely prolific aquatic invasive plant can double in size every ten days in hot weather and can quickly become a dense floating mat of vegetation up to six feet thick. The mats can travel with river currents and with tidal movement. Mats can also attach to structures in the water, limiting access to boats and reducing swimming areas.
About the Water Hyacinth!
Scientific name: Eichhornia crassipes. Perennial, floating aquatic plant. Stems: Stout, erect; may be connected by stolons; may be greater than 12 in (30 cm) in length. Leaves: Blade is generally oval to round and usually not greater than 4 in (10 cm) in width; leaf stem is somewhat to completely swollen, filled with spongy parenchyma tissue, 1-1.5 in (2-3 cm) diameter, generally longer than the blade. Inflorescence: funnel-shaped flowers borne on 2-6 in (5-15 cm) spikes.
Researchers also hope that this biological control will be more resilient an effective than existing biological controls such as the herbicides that are already in place to combat the invasive water hyacinth, but as of this date (11/2013) no evidence has been shown that any applications used is working.