Texas Wild Rice - Edwards Aquifer Authority

Texas Wild Rice

ESA Status: Endangered Species

Description: Texas wild-rice is an aquatic grass that is presently limited worldwide to a small segment of the San Marcos River. Texas wild-rice does not occur naturally in any other springs and was on its way to extinction until a researcher began a restoration project on the species. Wild-rice plants form large masses firmly rooted in the gravel bottom of the river. Stalks and leaves are completely immersed in the swift current .Flowering plants are rarely seen, and when present, their stalks do not extend very far above the surface. Listed as endangered by TPWD and USFWS, this plant is heavily impacted by recreational users of the river and floods, which may uproot the plant or strip off its leaves and flowers. Low flows make the plant vulnerable to herbivores or may cause the plant to be exposed and dry out.

Size: Average plant length varies between 3.3 to 6.6 feet with linear leaves that are up to 3.3 feet long, and 0.5 inch wide (Terrell et al. 1978).

Habitat: San Marcos Springs aquatic ecosystem. Texas wild-rice requires thermally constant temperatures, clear water, undisturbed stream bottom habitat, protection from floods, and unimpeded light for reproduction. The plant grows in swift currents, shallow areas near the middle of the river and in water up to 6.5 – 9.8 feet deep.