Hydrilla is a plant found in freshwater. The Hydrilla will grow to the waters surface from a depth of up to 20 feet. Hydrillas are a standard marine flora and can grow in a variety of peculiar water sorts. Hydrillas can grow in as small as a few inches of water or in as much as 20 feet of water. This plant can grow in oligotrophic (low nutrient) to eutrophic (high nutrient) conditions in water.  
 
This fresh water flora will only prosper in temperatures between 20 C and 27 C so it will not be found in harsher climates. The Hydrilla has long branches that spread out upon getting to the surface, shaping mats. The underwater stems of the Hydrilla can be as long as twenty five feet. in general off-white or yellowish in color. | The roots or Rhizomes of the Hydrilla are ofttimes yellowish or off-white in color. } The Hydrilla has several alternatives when it comes time to reproduce. Fragmentation, from seeds, from tuber, and turions (auxiliary buds) are ways how this pest procreates.
 
The Hydrilla has many advantages when equated to other plants. It can grow in very low light with 1% sunshine. These plants also take up the rich foods from its place so that the other native sources can’t get it. Hydrillas are marked as a pestilent pest because of their fast growth rate that makes them a menace to other native floras. Hydrilla is especially dangerous because it can almost entirely take over a body of water before appearing on the surface. Hydrillas will oftentimes choke out native aquatic plants because they take up so much surface area absorbing the sunlight and foods.
 
Millions of dollars are spent each year on weed killers and harvesting devices in an effort to keep this floras growth under control. Hydrilla harms the vegetation in the surrounding area making it near hopeless for fishermen to fish. Hydrilla is responsible for slowing water flow and congesting irrigation and flood- control canals. Hydrilla impedes swimmers, boaters and fishers alike. Mass amounts of Hydrilla can severely lower the oxygen levels of the water it is growing in.
 
The Elodea and Egeria are oftentimes confused with the Hydrilla. Hydrilla can be identified by the teeth found on the undersurface of the midrib. Elodea and Egeria do not have teeth present on their undersides. Neither Elodea nor Egeria has teeth on their underside. Because of the teeth, Hydrilla will feel rough. Hydrilla will feel rough due to the presence of the teeth on the undersurface of the plant. The blossoms the Egeria create are also bigger than the Hydrilla. 
 
Macro and micro invertebrates feed on Hydrilla. Upon dying, these micro and macro organisms decompose and become food for other land and aquatic wildlife. Bacteria and fungi decompose Hydrillas that die naturally and then create a food called rubble, which many aquatic creatures eat. Ducks ofttimes eat Hydrilla turions and tubers, but this is not a substantial source of food. Ducks will often feed on the tubers and turions of Hydrilla, but they don’t make a great diet.