News that the Asian citrus psyllid has been confirmed in three locations in Tiajuana, Mexico, only 1.9 miles from the California border has sent shock waves through the state's citrus industry. This comes a few weeks week after the psyllid and the deadly citrus greening disease it spreads was confirmed in New Orleans.

“It’s shocking,” Joel Nelsen, president of the Exeter-based California Citrus Mutual, says about the finds in Mexico.

The insects were not discovered by the U.S. Department of Agriculture’s Asian citrus psyllid trapping program, he says. Instead, they were picked up by a general pest trapping program.

“It’s extremely disconcerting for it to be discovered so close to San Diego County, where there’s ample enough host plants,” Nelsen says. “It’s created major activity on our part.”

Nelsen says the industry is still waiting to hear from the U.S. Department of Agriculture whether those psylla from Mexico carried the greening bacteria.

In the meantime, the state’s citrus greening industry task force will hold a conference call to evaluate its course of action, Nelsen says.

The California Department of Food and Agriculture is wrapping up its annual survey for the psyllid and greening and has not detected either pest, says Jay Van Rein, a department spokesman in Sacramento.

Inspectors annually survey about 25 percent of commercial citrus groves, as well as other high-risk areas, such as packinghouses and nurseries, where the pest might enter.

In light of the Tijuana finds, Van Rein says the state will tack additional psyllid traps onto its regular pest monitoring program.

Citrus greening, also known as huanglonging or HLB, is lethal to citrus, reducing yields and killing trees in a matter of years. The disease was first confirmed in the United States in Florida in September 2005, about seven years after the initial Florida discovery of the Asian citrus psyllid.

It spread to most of Florida’s citrus-producing counties in a matter of months, and state agricultural officials have given up hope they can eradicate it or the Asian citrus psyllid.

Texas has had the Asian citrus psyllid since 2001, and 37 southern counties remain quarantined. But so far, agricultural officials have not detected citrus greening.

The Asian citrus psyllid has been confirmed in three Louisiana parishes in the past month. In addition, a lime tree on a residential property in New Orleans tested positive for citrus greening.

The Louisiana State Department of Agriculture and Forestry in Baton Rouge continues to conduct delimiting surveys and sampling to determine how widespread the psyllid and greening are.

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