April 2006 :: Feature Story

States throughout the Southwest are famous for their tales of marauding cattle rustlers and deadly desperados.

Now there are new villains in the area, and they’re perhaps more dangerous than those black-hatted banditos of yore.

Salt cedars are a growing concern in the Southwest, where both cities and farmers have watched their groundwater supplies shrink in recent years as the plants deplete rivers and lakes. Once established, salt cedars form impenetrable thickets that clog rivers and prevent wildlife from using them. The shrubs drink twice the water consumed by their native predecessors.

If given a chance to germinate, however, native trees like cottonwoods can muscle out salt cedars to reclaim their former dominion, researchers in Texas Tech University’s Department of Range, Wildlife and Fisheries Management have found.

“Once they germinate, cottonwood and willow seedlings can compete with salt cedars very well,” says Dr. Loren Smith, Kleberg Professor of wildlife ecology at Texas Tech.

The problem is getting them to germinate. A single salt cedar tree can produce as many as a million seeds a year, Smith says. The seeds can germinate anytime the soil is moist from April through November.

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Dr. Loren Smith, Kleberg Professor of wildlife ecology at Texas Tech and his team are waging war on armies of salt cedars.

Cottonwood seeds, by contrast, also need damp soil to germinate, but can only do so for a few brief weeks between the end of May and the beginning of June.

Texas Tech researchers, working for 10 years in collaboration with the U.S. Fish and Wildlife Service, found that by clearing the land of salt cedars — removing their root crowns from the ground — and then flooding the land during a cottonwood’s germination period, the trees can get the foothold they need to beat out salt cedars.

Smith wants people to be aware that programs do exist to help share the costs of replacing native habitats. Both the Department of Agriculture and the Department of the Interior provide funds for this purpose.

Cory Chandler