Partial plant quarantine: “better than none” or “a little bit pregnant”?
By Tara Treasurefield
SEEMS THE RECENT invasion of the glassy-winged sharpshooter has state and county officials scrambling for a plan. On June 23, Sonoma County Agricultural Commissioner John Westoby said, “There’s no hope for a state interior quarantine,” to control the glassy-winged sharpshooter, a pest that devastates vineyards and not long ago was detected in the North Bay. But as recently as early June, Joseph Gray, senior biologist at the Sonoma County Agricultural Commission, said that a state interior quarantine would be “ideal,” and that monitoring for the pest was the first step toward quarantine.
According to Westoby, the final decision is in the hands of William Lyons Jr., secretary of the California Department of Food and Agriculture. Westoby says, “We don’t think the secretary will approve a complete ban, [though] that would reduce the threat quite a bit.”
Every week, the Agricultural Commission inspects 40-45 shipments of nursery stock from Southern California. “Without those shipments,” says Westoby, “the threat of a glassy-winged sharpshooter infestation would be less. However, we also have to look at [the economic viability of] our local nurseries.
“Where are they going to get their plant material?”
Last week, the Napa County Board of Supervisors jumped into the bureaucratic quagmire by announcing that it is considering a ban on ornamental plants that would be the first of its kind in the state–an action that could cost nursery owners millions of dollars in losses. Now the politically influential Sonoma County Grape Growers Association is thinking about asking for a similar ban here.
Westoby fears that quarantine may be seen as an illegal “restraint of trade.”
Bob Shaffer, president of the North Coast Chapter of California Certified Organic Farmers, says, “We are very much in favor of quarantine.”
Shaffer wants assurance that incoming nursery stock is pest-free. “While people may still bring small amounts up in their cars, that’s a minor portion,” he says. “That does not equate with thousands upon thousands of plants coming up.”
Shaffer asks the nursery and wine industries to “be heroes. Spray your stock or don’t bring it in,” he says. “I heard a grower in Napa say that instead of bringing up green growing plants from the south, they’re going to bring up dormant plants [that don’t harbor the pest] and instruct their nurseries to put those plants in the ground. This is smart.”
GRAPE GROWERS in infested southland areas–and local wineries, like Benziger, that import some grapes from Southern California–oppose quarantine, even though the pest is seen as a serious threat to the state’s $2 billion grape-growing industry. But Doug Davis, executive wine master at Sebastiani Vineyards, says, “It would be crazy not to try to keep the [glassy-winged sharpshooter] out.
“At this moment, our position would be to not accept grapes from infested areas.”
Sebastiani grows all the grapes it needs in Sonoma County. Nick Frey, executive director of the Sonoma County Grape Growers Association, expects the association’s board to discuss quarantine at its next meeting on July 11.
“We’re certainly taking a look at whether a quarantine would be beneficial. There are some issues around it; on the other hand, trying to limit the potential introduction is a high priority for us. We think that requires something more than what’s been done to date, and quarantine is certainly an option.”
The Sonoma County counsel is reviewing a CDFA model ordinance for restricting shipments of nursery stock and bulk grapes. The ordinance allows shipments from infested areas but not to uninfested areas. It attempts to ensure that shipments are from noninfested premises or that if they are from infested areas, they are treated at the point of origin or are certified as free of the sharpshooter.
The proposed ordinance defines an infestation as “five or more adult [sharpshooters] within any five-day period and within a 300-yard radius,” or a fresh viable egg mass or nymph unassociated with a shipment, or multiple sharpshooter life stages in a “nonregulatory situation.”
An area is infested if it’s “within one mile of a [past] infestation”; a county is infested if it contains one or more infested areas.
What if efforts to keep the glassy-winged sharpshooter out of Sonoma and Napa counties fail? The state Food and Agricultural Code gives the agricultural commissioner the authority and responsibility to spray infested private property, including organic farms, with or without permission of the property owner–a possibility that has drawn angry criticism from local residents who want county officials to explore nontoxic alternatives.
Mike Smith, deputy agricultural commissioner in Sonoma County, says, “If we wanted to maintain a quarantine, we’d be obligated to treat [the imported plants]. There may be organically approved materials that we could utilize in a situation like that. We’d have to go back to the [CDFA] scientific panel and see if they think it’s effective.”
MR. SCIENCE: Hey, kids, now you can join the front lines of the battle to nip the glassy-winged sharpshooter in the bud. Here’s how: The Sonoma County Grape Growers Association is coordinating a countywide monitoring program. All you’ve got to do is place four sticky traps in your vineyard and then check for the little buggers weekly. Mapping locations will be shared by county officials. If you want to place and monitor traps, call the SCGGFA at 206-0603. Become a junior viticulturalist today! Greg Cahill
From the July 6-12, 2000 issue of the Sonoma County Independent.
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