Saltcedar Management in the Upper Brazos River

Saltcedar (Tamarix spp.) is non-native to Texas and has become highly invasive across more than 2 million acres in the southwestern United States. Ground-nesting birds such as turkey and quail suffer from saltcedar invasion, as do fishes that have specific habitat requirements. Saltcedar, in contrast to mesquite and other “nuisance” brush species, grows throughout river floodplains at much higher densities than native plants, consuming large quantities of water and often affecting river flows. As it grows along the river bank, saltcedar can form dense thickets that displace native plants, trap sediment and change the shape of the river channel, reduce water availability, and impact water quality. As a result, habitat for fish and wildlife and even for livestock grazing is degraded.

In 2015, TPWD began a partnership with landowners as well as other agencies to manage saltcedar in the Brazos River headwaters region. Effective, targeted management of saltcedar using targeted, aerial herbicide application can help to restore or conserve habitat for these fishes and support healthy river function and diversity of plants and wildlife. Imazapyr, the herbicide we use to treat saltcedar, will also kill grasses in the treatment area; these impacts are temporary and grasses should begin to regrow within eight to 10 months after treatment. In areas where nontarget damage must be avoided (e.g., Cottonwoods present), more precise "touch-up" treatments using an ATV can help to enhance control. For more information on project participation, landowners should see the Resources section below.

Key project partners include TPWD Inland Fisheries and Wildlife Divisions, the USFWS Partners in Fish and Wildlife Program, University of Texas – Bureau of Economic Geology, Texas A&M AgriLife Extension, and Texas Tech University.

Project Status Highlights

  • Aerial surveys of saltcedar infestation have been completed on the Double Mountain Forks, Salt Fork, White River, and main stem of the Brazos River down to Possum Kingdom Reservoir.
  • Approximately 50 landowners and numerous partners are participating in large-scale efforts to manage saltcedar in the Upper Brazos River watershed and improve habitat for fish and wildlife.
  • In 2016–2017, 6,700 acres along 178 miles of the Double Mountain Forks of the Brazos River were treated with herbicide to manage the impacts of invasive saltcedar.
  • Saltcedar treatment has not yet begun on the Salt Fork or main stem of the Brazos. In summer 2018, we plan to continue to fill in treatment gaps on the Double Mountain Forks and expand treatment priority to the Salt Fork.
  • Saltcedar beetles, a biological control agent, are present but population numbers remain low in the treatment area. Small, untreated creeks create "refuge areas" for beetles so that they can continue to help with control.
  • Research studies are underway at sites throughout the upper watershed to evaluate the effects of saltcedar control on water budget, water quality, river channel shape, and the riverside plant communities that provide important habitat for wildlife.
  • Planning for restoration replanting of Cottonwood poles is underway. Interested landowners should contact us for more information.  

For more details on any of these events or programs, contact:
Monica McGarrity, Aquatic Invasive Species Team Leader - 512-552-3465
Kevin Mayes, Aquatic Biologist, River Studies - 512-754-6844 Ext. 225

Map of rivershed showing areas treated in 2016 and 2017