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WATERHYACINTH 



BOTANICAL 



The tropical genus Eichhornia (also listed as Piaropus) in- 

 cludes three species in South America besides waterhyacinth, 

 E. crassipes. The latter is a pest in North, Central, and South 

 American countries, and in Australia, India, and Java, Africa, 

 and other areas. In the United States it is confined by climate to 

 the Southeastern Coastal Plain and a few California localities. 



The plant thrives either free-floating, buoyed by bladderlike 

 bases of the leaf stalks, or attached by roots to muddy margins. 

 Rapid propagation occurs by offsets of small new plants. Three 

 Louisiana plants are reported to have multiplied into 3,000 plants 

 within 50 days by this means. Waterhyacinth also produces 

 viable seeds, but propagation by seedlings appears to be negli- 

 gible except on floating mats. The plant is also called hyacinth, 

 lily, water orchid, and river raft. 



IMPORTANCE 

 Waterhyacinth *s beautiful flowers and curious form make it a 

 popular aquarium specimen, but in other respects it is a weed. 

 Its hindrance of navigation is so great that nearly 15 million dol- 

 lars have been spent in efforts to control the pest during the past 

 40 years. In addition, waterhyacinth causes much harm by 

 destroying usefulness of fish and wildlife habitat, hinders drain- 

 age, and increases malaria hazard. A 1947 report (Lynch and 

 others) on the harmfulness of waterhyacinth and alligatorweed 



