NACOGDOCHES COUNTY (October 14, 2009)—More than 100 acres of giant salvinia was discovered Tuesday in the Angelina River and Texas Parks and Wildlife Department officials are concerned that runoff from the recent rain could push the infestation closer to the main portion of Sam Rayburn Reservoir.

The free floating aquatic fern was found in a backwater area called Estes Lake about 10 miles upstream from Marion Ferry and Kingtown in Nacogdoches County, the department said Wednesday.

It was evidently contained for more than a year by shallow water and dense brush, the department said.

Giant salvinia, which the department says is “arguably the most problematic aquatic vegetation in Texas,” reached epidemic proportions on Toledo Bend, where it was discovered in 1998.

Oil-spill booms in Coleman Creek on Sam Rayburn contain persistent infestations, but the fern is defying control efforts on B.A. Steinhagen, and the fate of Caddo Lake is uncertain because of an expanding infestation, the department said.

Giant salvinia is capable of doubling the area it covers in as little as five days, disrupting ecosystems and leaving bodies of water unsuitable for either boating or fishing.

It’s now firmly established in 11 Texas reservoirs, the department said.

The Parks and Wildlife Department asks those who use the state’s waterways to report possible sightings of giant salvinia to:

Howard Elder
Texas Parks & Wildlife Department
Aquatic Habitat Biologist
409-384-9965
Howard.Elder@tpwd.state.tx.us