Traps, quarantine prevent costly citrus bug outbreak

Cronkite News Service
Cronkite News Service

By Anna Consie / Cronkite News Service

YUMA, AZ – Stopping every 50 feet along the edge of a citrus grove, Alex Bellotti pulls a bright yellow insect trap from a tree and quickly scans it for a bug the size of a ballpoint pen tip.

An inspector for the Arizona Department of Agriculture, he'll make dozens of stops today, collecting and replacing the glue traps before bringing them to a screening facility to be examined under a microscope.

There are thousands of such traps around Yuma County as part of an intensive effort to keep the Asian citrus psyllid (pronounced SILL–id) – and the fatal tree disease it can carry – out of the state. The invasive species has already decimated citrus groves in Florida and has footholds in neighboring Southern California and Mexico.

"We have to keep good watch," Bellotti said. "California, Texas – they have them, but we really don't."

So far, the traps have turned up 11 Asian citrus psyllids in Yuma County and one in Nogales. None have carried citrus greening disease.

But the initial discovery of five bugs in 2009 prompted a quarantine for most of Yuma County, the main producer of citrus in the state, said John Caravetta, the associate director of the Arizona Department of Agriculture.

"Asian citrus psyllid has the propensity to be very damaging and very devastating," he said.

Citrus greening disease, spread by infected psyllids, causes the fruit to stay green and turn sour, and it eventually kills the tree. Millions of trees in the southeastern U.S. have died, severely damaging the citrus industry in Florida.

Because the bug can be transported on leaves, Arizona's quarantine placed restrictions on the movement of citrus trees. It initially banned nurseries in Yuma from selling trees outside the quarantine area.

That was particularly challenging for Sunset Nursery, a fourth-generation citrus business that provides citrus stock for much of the state, said Stacey Loghry, the office manager.

"The whole citrus industry was crippled for 18 months," she said.

In order to sell outside of the quarantine area, Sunset Nursery was required to build screened houses where the trees could be quarantined for 60 days prior to sale.

And while the restrictions are challenging, Loghry said, if the disease gets into the state it could shatter the industry.

"At this point it's just a pest, but if you get the wrong bug on the wrong plant then we could lose the whole industry," she said.

The quarantine also placed restrictions on fruit sales out of Yuma, but Mark Spencer, who owns and runs Associated Citrus Packers Inc. with his brother, Bill, said the firm now has to wash all lemons shipped out of state for juice. It's a slight change that hasn't had a significant financial impact, he said.

"Compared to the citrus nurseries we didn't suffer as bad," he said.

But the disease isn't only a threat to commercial citrus, the Department of Agriculture's Caravetta said. Most of the psyllids found in Arizona so far have been on trees in residential areas.

"There is a very real possibility they could spread to Maricopa County and the residential citrus areas there," he said.

Glenn Wright, a professor and citrus specialist at the University of Arizona's Yuma Agricultural Center, said citrus greening disease will eventually get into Arizona but won't do as much damage here because of the drier climate and the state's aggressive response.

"I'm almost certain we'll get it here. Will it be as bad as Florida? No, absolutely not," he said.

The quarantine in Yuma County will stay in place until no psyllids have been found for two years.

That will keep Bellotti out checking traps for the foreseeable future.

"Pretty much anywhere we can find a tree we'll put a trap and be out checking them," he said.

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