From the archive record
The water hyacinth, popularly known as 'kulavazha' in the state, is one of the most invasive and gregarious aquatics weeds of Kerala widely distributed all. Eichhornia crassipes, commonly known as (common) water hyacinth, is an aquatic plant native to the Amazon basin, and is often considered a highly problematic invasive species outside its native range. Water hyacinth is a free-floating perennial aquatic plant(or hydrophyte) native to tropical and sub-tropical South America. With broad, thick, glossy, ovate leaves, water hyacinth may rise above the surface of the water as much as 1 meter in height. The leaves are 10--20 cm across, and float above the water surface. They have long, spongy and bulbous stalks. The feathery, freely hanging roots are purple-black. An erect stalk supports a si