Editorial: Has tamarisk met its match?

Sunday, Aug. 12, 2007 | 7:39 a.m.

The level of the Colorado River is dropping ever lower because of drought, the West's population boom and ... the tamarisk plant.

In a year this non-native, deeply rooted and fast reproducing plant sucks in almost twice the amount of river water allotted to all of Southern Nevada.

Until now, battles against it have been about controlling its spread - eradication, even with the use of bulldozers, fire, saws and poison, had always been thought of as impossible.

But a Denver Post article last week spotlighted a new tactic. At selected tamarisk stands in Utah and Colorado, hundreds of thousands of tamarisk leaf beetles were released in 2004 and 2005.

Under the supervision of scientists, the beetles are so far fulfilling their mission, that of eating tamarisk leaves and leaving acres of dead tamarisk in their wake.

The Las Vegas Sun's Mary Manning, who has written extensively about tamarisk, learned that the beetles were collected in northwestern China and raised in nurseries in Lovelock . For less than $10 an acre, they are being far more successful than aggressive past efforts, which were costing up to $3,000 an acre.

Tamarisk plants, also known as salt cedars, were imported by Western settlers in the mid-1800s from the Middle East and North Africa. They were used for landscaping, erosion control and for attracting honeybees. Today they have no redeeming value. They are unfit for wildlife habitat and contaminate surrounding soils.

The estimated 1.6 million acres of tamarisk in the West include the Las Vegas Wash and along the Virgin River, which should instead be dotted with native cottonwood and willow trees. Both areas deliver water to Lake Mead, which supplies 90 percent of the water for Southern Nevada.

Years of research preceded the beetle release and we were glad to learn that the field tests in Colorado and Utah will be studied for at least five years before any wider release is considered.

The non-native beetle sounds like a godsend, but then, so did the tamarisk 150 years ago.