Feds: Tamarisk no thirstier than trees
The water-swigging tamarisk isn’t quite the heavy drinker it’s been portrayed to be, the U.S. Geological Survey said.
One finding of a study done at the behest of Congress is that native trees such as cottonwoods and willows consume about as much water from their stands along western streams and rivers as do the nonnative tamarisk and Russian olive, the survey said.
Removal of tamarisk, also called salt cedar, along rivers leaves a void filled by other plants that consume about the same amount of water as tamarisk, the report said.
In sum, the survey said, tamarisk might not be as detrimental to wildlife and water availability as believed.
“None of the published studies to date, which include projects removing very large areas of salt cedar, have demonstrated production of significant additional water for human use,” said Curt Brown, director of research for the Bureau of Reclamation.
The finding, though, is unlikely to change the approach to tamarisk in western Colorado, where the Grand Junction-based Tamarisk Coalition already had reached a similar conclusion about the thirst of the plant.
There are plenty of reasons other than water conservation to remove tamarisk, coalition Executive Director Stacy Kolegas said. Removing the plant eliminates a “monoculture of tamarisk” by allowing a variety of plants to take root in former tamarisk stands, Kolegas said.
Tamarisk “does alter the ecosystems that it moves into,” Colorado Division of Wildlife spokesman Randy Hampton said. “We have found that replacement of cottonwood stands by tamarisk makes river access more difficult for animals and changes the kind of birds that may utilize an area.”
Tamarisk, which was imported to the western United States as an ornamental plant, is unlikely to see its reputation restored by the study.
“People have used tamarisk as the evil water guzzler as a justification and marketing for grant writing,” Colorado River Water Conservation District spokesman Chris Treese said. “You’ll still see it.”
Among its other sins, tamarisk still is a salt accumulator, thus its other name, and that won’t be changed by the survey, Treese said.
And the fact remains, Treese said, “You’re not going to save Las Vegas by cutting tamarisk.”