Texas Gardening: Texas Native Plant Pictures ( Aquatic & Bog ), 1 by htop

htop wrote:
Fanwort, Washington Grass, Fish Grass (Cabomba caroliniana - Synonym: Cabomba caroliniana var. caroliniana), Cabombaceae Family, perennial, blooms May to September

Cabomba caroliniana is common aquatic perennial found in the southeastern United States as well as some parts of South America. It occurs from Texas to Florida, north to New England (where it can be found in Connecticut, Rhode Island, Massachusetts and New Hampshire) and west to Kansas. It is also present in Oregon and Washington. It grows so aggressively in some regons that it has been declared a noxious, invasive weed.

For more information see its PlantFiles entry:
http://davesgarden.com/pf/go/1260/index.html

The small blooms are very noticeable. Look closely to see the oyygen bubbles it produces.