Moth quarantine to expand

Most of Santa Rosa soon will come under an expanded quarantine area for the light brown apple moth after recent discoveries of the invasive pest.

The quarantine will have little effect on city residents, except that by law they are prohibited from taking home-grown fruit, vegetables and other plant materials outside the area.

But the changed boundaries suggests the moth, a native of Australia, continues to expand into the North Bay. In winter the pest normally goes dormant, but 10 moths were trapped in the county in December and another 14 to date this month, said Sonoma County Agricultural Commissioner Cathy Neville.

The expanded quarantine area is expected to be confirmed by the state within the next two weeks, county officials said. Its boundaries will reach from the outskirts of Forestville in the north to the Marin County line in the south and from west of Petaluma to Napa County. In the Sonoma Valley, the quarantine will extend north almost to Glen Ellen.

Another quarantine area exists around Healdsburg.

State and federal agricultural officials first confirmed the existence of the moth in California three years ago.

That year the state began aerial spraying of a chemical that disrupts moth mating over Santa Cruz and Monterey counties. But it later dropped that program after intense public opposition.

Critics maintain the moth has been here for decades, is too difficult to eradicate and can be controlled by farmers using routine pest management techniques.

The moth first showed up in traps in Sonoma County in early 2008. To date 180 moths have been trapped here.

That count remains far lower than in most of the Bay Area, certainly compared to the 57,000 moths found the last three years in San Francisco or the 42,000 found in Alameda County.

Nonetheless, the steady growth in numbers this year suggests the moth is relatively new to the county, officials said. They base that conclusion on the lack of moths found when traps first were set out three years ago.

If the moth had been residing here for years, "they should have shown up throughout the county, and they didn't," said Paul Turano, a county agricultural biologist.

Preliminary figures indicate the county will have about 300 square miles of land under quarantine. That includes more than a third of the county's 62,000 acres of vineyards.

To date the state has monitored the pest's presence in the county, but has taken no measures to control it.

Within quarantine boundaries, farmers must take steps to prevent spreading the moth outside the area. But county agriculture officials last year had growers sign agreements to maintain certain farm practices, and everyone was able to successfully harvest their crops.

Nick Frey, president of the Sonoma County Winegrape Commission, said the quarantines resulted in "minimal impact" for his members last year.

"I assume they're prepared to continue to deal with it," he said.

State officials last year held hearings on an environmental impact report for eradicating the moth. That plan is expected to be completed within the next several weeks, said Steve Lyle, a spokesman for the Department of Food & Agriculture.

Once that report is completed, a scientific advisory panel will tackle the question of whether the moth still can be eradicated, and if so, the best way to accomplish that, said Larry Hawkins, a spokesman for the U.S. Department of Agriculture.

Hawkins insisted the moth numbers are increasing statewide not because of extra trapping but because the pest population keeps increasing.

"It's establishing itself and the moths are producing at a greater rate," Hawkins said. "And that's why it's easier to find them."