INTRODUCTION 



Man's attraction and search for botanical species which are unique 

 in structure, food potential, floral characteristics, productivity or 

 ability to survive in specific environmental situations have resulted in 

 the introduction of numerous plants outside of their native range. Such 

 introductions may result in an exotic species becoming established in 

 a habitat optimum for growth in the absence of its naturally limiting 

 environmental factors or organisms. Once freed of these naturally 

 limiting conditions, certain exotic species may proliferate to such an 

 extent that the population interferes with man's intended use of its 

 habitat. 



The waterhyacinth, Eichhornia crassipes (Mart.) Solms, a perennial, 

 floating aquatic plant, is an example of such an exotic species. The 

 waterhyacinth is generally considered to be a native of Brazil from 

 where it has spread to nearly all sub-tropical and tropical regions of 

 the world where conditions favor its growth (Penfound and Earle, 1948; 

 Bock, 1966). Since its introduction into the United States in the mid 

 1880' s, the waterhyacinth has proliferated to such an extent that it has 

 created serious water resource management problems such as 1) inter- 

 ference with commercial and recreational navigation, 2) reduction in 

 water conveyance capabilities of streams, rivers, and man-made flood 

 control structures and waterways, 3) adverse modification of fish and 

 wildlife habitat, and 4) threatening public health by providing habitat 



