ALBUQUERQUE, N.M. (AP) _ Salt cedar has invaded waterways throughout the West, and state and federal officials are targeting the thirsty, nonnative species because of dwindling water supplies and the threat of wildfire.
They've already tried chain saws, bulldozers, herbicides and fire. Their latest weapon is a small brown leaf beetle that yearns only for the pink-tipped branches of salt cedar.
The beetles have already shown their stuff in Nevada where, in one season, they ate the green off a 400-acre patch of the fast-growing trees. They also have been released at test sites in Texas, Colorado, Utah, Wyoming and California.
``There are very few things that eat the leaves of a salt cedar tree, and these beetles are one of them,'' said Dave Thompson, an entomologist at New Mexico State University.
Thompson, in cooperation with the U.S. Department of Agriculture and the U.S. Fish and Wildlife Service, in August released about 600 of the leaf beetles along the Pecos River near Artesia. It marks the first time they were released in New Mexico.
Researchers will track the beetles _ about the size of a pencil eraser _ to see how they respond to New Mexico's shorter days and cooler winters. Thompson is hopeful the beetles make it through the winter and lay eggs next spring.
The creation of a beetle army was initiated more than a decade ago through the USDA's Agricultural Research Service. The program has continued over the years with countless tests in the lab and in field cages.
Researchers initially chose the Chinese leaf beetle, which comes from the salt cedar's native region. But to compensate for the shorter and hotter days of the Southwest, they also are studying subspecies of the beetle from Crete, Tunisia and Uzbekistan.
Beetles released in southeastern New Mexico were from Crete. Thompson's team plans to release the other two varieties next season to determine which does the best in New Mexico's climate.
Salt cedar, also known as tamarisk, was brought to the United States more than a century ago as an ornamental plant and soil stabilizer. It wasn't long before the trees took over, gulping up water, killing native plants and growing into impenetrable stands that became fire hazards.
In Albuquerque, two wildfires fueled by salt cedar and other nonnative trees raced through the wooded area along the Rio Grande this summer. The fires forced the evacuations of hundreds of homes and prompted city officials to take a closer took at eradicating invasive plants and restoring cottonwood and willow trees along the river.
The drought persisting across the West also puts salt cedars in the cross-hairs. One mature salt cedar can consume 200 gallons of water a day. A mature tree also can produce as many as 500,000 seeds a year, making elimination nearly impossible.
Sen. Pete Domenici, who represents New Mexico, is pushing legislation to find solutions to the problem and assess potential increases in water availability by controlling the plant.
``I believe that we can move forward in an environmentally sensitive manner that will save water, reduce fire danger and improve range conditions,'' he said.
Environmentalists have talked about the benefits of getting rid of salt cedar, highlighting improvements the trees' eradication would have on the habitat of the endangered Southwestern willow flycatcher.
The bird, which lives along the Rio Grande in central New Mexico and in parts of Arizona, has been forced to nest in salt cedar because the trees have pushed out native vegetation.
The flycatcher is the reason it has taken so long to release the beetles in New Mexico. Fish and Wildlife officials were concerned about the effects it would have on the bird; they agreed to let researchers release the beetles along the Pecos because it was far enough away from the flycatcher's habitat.
Thompson said he hopes to release beetles along the Rio Grande next season if Fish and Wildlife agrees. The permit process for allowing beetles along the Rio Grande has been under way for five years.
``The Rio Grande is a great place to release because other vegetation is there,'' he said. ``Along the Rio Grande, there is grass and willows that are competing with salt cedar. If we have something to take down the salt cedar, other vegetation can make a comeback.''
Elizabeth Slown, a spokeswoman for the Fish and Wildlife Service in Albuquerque, said it's imperative that the flycatcher is not left without a home.
``It would be terrible for salt cedar to be here one season and not the next without something to replace it,'' she said. ``That's the tough part, having a place where the Southwestern willow flycatcher can nest.''
Scientists hope the beetle can put a dent in salt cedars but acknowledge that it's not a magic bullet.
``The beetle is certainly another option,'' Thompson said. ``The key to this is trying to come up with an integrated control of salt cedar. We can combine the beetle with these other treatments and keep the plants from ever coming back.''
On the Net: New Mexico State University and U.S. Department of Agriculture
