Zizania texana only grows in the spring fed aquifer named Edwards Aquifer in Central Texas along the San Marcus River in Hays County. The San Marcus River is identified as having the greatest diversity of aquatic organisms than any other ecosystem in the Southwest of the United States. 

The rodent Nutria (Myocaster coypus) is the only known animal that consumes Texas' wild rice and is also threatened due to the decrease of its food source.