Researchers, engineers team up on saltcedar

The U.S. Bureau of Reclamation has a new tool in its efforts to control invasive saltcedar at Elephant Butte and Caballo reservoirs in southern New Mexico.

Developed by New Mexico State University, it’s a tractor-mounted rig for wiping herbicide directly onto saltcedar plants. It can be used on regrowth following mowing or on newly established plants. It covers a 24-foot swath at a time, without harming the grass and other plants growing under the saltcedar.

The supersized, heavy-duty carpet-roller applicator system was designed and built by staff and students in NMSU’s Manufacturing Technology and Engineering Center, working with Kirk McDaniel, a professor in the Animal and Range Sciences Department, and Brent Tanzy, resource management specialist with the Bureau of Reclamation’s Elephant Butte Field Division.

The bureau has been fighting saltcedar around the reservoirs since the 1950s, Tanzy said. The invasive, fast-growing plants, also known as tamarisk, are notorious for using large amounts of water, replacing native vegetation and increasing the intensity of brush fires. There are 6,000 to 7,000 acres of saltcedar at Caballo Lake and about 5,000 acres at Elephant Butte, Tanzy said. “Historically we have mowed it, but we have been trying to move beyond the mowing.”

Saltcedar plants grow back quickly after mowing. Spraying the mowed plants with herbicide also kills the grass and other native vegetation that the bureau would like to re-establish.

With funding from the bureau, McDaniel has been researching the use of carpet-roller applicators to wipe herbicide directly on the saltcedar without damaging the grass. But commercially available carpet-roller applicators, made for use on turf or row crops, were not big enough or rugged enough for the field situations at Elephant Butte and Caballo, so McDaniel and Tanzy approached Wes Eaton, a project manager and engineer at M-TEC in NMSU’s College of Engineering, and described what they needed.