Worried that the light brown apple moth could spread, two key trading partners have revised rules for farm products grown in infested California counties. Canada and Mexico changed their regulations for farmers exporting to those nations and have barred host crops from within the quarantine area.

Farmers and nursery owners in affected counties are still assessing the effects of the rule changes.

"Farmers tend to see the impact of invading pests first, but the light brown apple moth will also hurt home gardens and our natural environment," says California Farm Bureau Federation President Doug Mosebar who farms diversified crops near San Ynez. "Other places don't want the moth, and they'll clamp down on our farmers to make sure that it doesn't move. The trading restrictions pose a particular burden for organic farmers and for small-scale farms and nurseries that sell products in Canada and Mexico.".

The U.S. Department of Agriculture quarantine governs a 1.5-mile radius around any site where an apple moth has been confirmed. This results in numerous small quarantine zones in several California counties.

As of Feb. 29, 17,393 moths have been trapped in 13 California counties, according to California Department of Food and Agriculture reports. The largest infestations are in Santa Cruz and San Francisco counties.

To reduce the risk, managers within the Canadian Food Inspection Agency have created larger, contiguous quarantine zones. The Canadian agency traditionally has used county-level regulations. But after studying the California eradication and suppression programs, managers decided two zones that grouped all of the smaller quarantines into a northern and a southern region were acceptable.

Canadian agency officials say they will continue to monitor the situation and could make adjustments as required.

Even if a product comes from outside the quarantine zones, USDA inspectors must certify it is free of the light brown apple moth before it can be shipped to either Mexico or Canada.

"Since we first detected the light brown apple moth, one of our primary concerns has been the affect it would have on California's food supply," says California Agriculture Secretary A.G. Kawamura. "These new regulations demonstrate the complex threat posed by the moth not only to our environment and habitat, but also to our ability to produce a reliable and sustainable food supply. As growers incur more costs to meet export requirements, it has a negative impact throughout the entire food distribution system."

Canada is the No. 2 foreign market for California farms and ranches, purchasing almost $1.9 billion in products annually. The two leading farm exports to Canada, lettuce and strawberries, are grown primarily in counties now affected by light brown apple moth quarantines. Mexico purchases more than $560 million in California farm products each year. Strawberries, nursery crops and lettuce are among the top 10 products that Mexican buyers purchase from California.

The light brown apple moth, an Australian native, has a host range of more than 2,000 plant species, including stone fruit, grapes, strawberries, peppers and caneberries. The pest is endemic to Hawaii and New Zealand.

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