It's round three in the search for the right beetle to bug the water-swilling salt cedar.

"Biological control - there's a lot of art to it," said Jerry Michels, professor of entomology at the Texas AgriLife Experiment Station near Bushland. "You have to be on the ground watching and figuring out why something's not working. There's no cookbook to it."

First it was beetles from Greece, then Uzbekistan, and this year the ones to really watch are from China. Michels has the beetles working in enclosures at the experiment station and near Lake Meredith.

"All three may take off eventually," Michels said. "It takes time to get acclimated."

The work is intended to allow more water to get to Lake Meredith. The Bureau of Land Management estimates an acre of thick salt cedar can suck up 2.2 million gallons of water each year. The Texas State Soil & Water Conservation Board puts a mature plant's use at up to 200 gallons of water per day.

The Canadian River Municipal Water Authority is helping fund the research that will complement its efforts to kill salt cedar by spraying them with herbicides.

"We're helping fund the research by putting in about $30,000 a year," said Kent Satterwhite, general manager of CRMWA. "We think it could be huge if it pans out.

We're optimistic."

The beetles from the Fukang region in China seem the best adapted of the varieties tried in past years, so Michels is also optimistic.

"We're still in the colonization stage," Michels said. "We just don't have enough numbers yet."

He keeps the bugs in net-covered enclosures to allow them to go through some of their life cycle and bond.

"We have to keep them together so they can find each other," Michels said. "There's a phermone that keeps them together. Then when we take off the cage, they don't fly off to Borger."

The trees in the enclosures at Bushland show the damage the beetle s can do. As they chew on the plants, they eventually eat the bark all the way around a branch, cutting off the circulation of nutrients and killing that branch.

But bugs aren't the only weapon the salt cedars could fall to.

CRMWA is planning to continue its spraying campaign against the trees.

It recently asked for bids from aerial sprayers.

The work along the Canadian River began in 2004 and has covered sections from Ute Lake in New Mexico to and around Lake Meredith.

"We hope to spray pretty much everything we have left this year," Satterwhite said.

Results seem positive.

"We are seeing a little regrowth and some growth in places we didn't get to where the lake has gone down more," Satterwhite said. "Plus, there's still some seeds coming down from upstream."

The big question mark is the Canadian River Cattle Company's 32 miles of river running east from about the New Mexico border.

CRMWA has filed a condemnation suit ag ainst the ranch to establish an easement to allow it to spray along the river.

"We hope to settle before it comes to a hearing," Satterwhite said.

David Nutt, a wealthy lawyer from Jackson, Miss., and veteran of asbestos, insurance and tobacco industry lawsuits, owns the 71,000-acre ranch and has so far not allowed spraying that he said would damage wildlife habitat.

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