Growers Urging Action to Thwart Olive Fruit Fly


For three generations there’s been an Erickson growing olives in the rich soil of Glenn County on the north end of the Central Valley. John Erickson fears he could be the last, all because of a very small but formidable foe: the olive fruit fly.

Over the last three years the insect has hitchhiked up from its roost among the ornamental olive trees of Los Angeles and infiltrated vast portions of California’s farm belt.

And olive growers like Erickson don’t believe enough is being done to fight it.

The spread of the pest has been alarming. The first was captured in 1998, snagged by a trap set for Mediterranean fruit flies in Westwood. In 1999, a single olive fruit fly was trapped in Tulare County, which boasts more than half the state’s commercial olive acreage. By 2000, as many as 300 of the flies were found in the county.


Now state agriculture officials talk of reclassifying the fly, shifting it from the cross hairs reserved for feared pests that need to be stamped out. Instead, the olive fruit fly would be accepted as a testy part of the natural environment in the Golden State, a pest to be fought on a case-by-case basis like aphids on a rosebush.

That, olive growers say, would be a stinging retreat that could help drop the curtain on an industry that is unique in the country. California is the nation’s only olive-processing state.

“If the fly cannot be controlled, it could potentially devastate the industry,” said Jan Nelson, manager of the California Olive Committee, an industry group.

Such widespread sentiments come as the state has poured huge sums over the last few years into a battle against the glassy winged sharpshooter, which threatens the wine industry. Olive growers gripe that California agriculture officials have failed to mount a similar effort to thwart a pest that threatens their industry.


“We felt like a poor stepchild, because we are a small industry,” Erickson said. “But it would have been nice to get a little money thrown at us.”

State officials say such assessments don’t recognize a flurry of actions in recent years and the reality that the olive fruit fly has established a firm hold in the state. Complete eradication, they say, is now deemed impossible.

Early on, the state attacked the problem as it has dangerous pests in the past, from the Medfly to the sharpshooter, setting traps and spraying infested areas. State agriculture scientists began looking into it. Experts from Europe, where farmers have coexisted with the fly for centuries, were brought in.

The fly couldn’t be stopped.


“It quickly became obvious it had spread all over the place,” said Pat Minyard, the state Agriculture Department’s pest-detection chief.

Politics and economic realities also came into play. While the wine industry enjoys considerable clout in Sacramento, the olive industry is a relative pipsqueak by comparison. With 35,000 planted acres, olives fetched $32 million in sales, contrasted with $2.8 billion for grapes in 2000, according to the state.

The pest has set its sights on an agricultural commodity that of late had seen a marked upsurge. Interest in olives has burgeoned over the last decade with the growth among boutique farmers producing high-quality extra virgin olive oil.

Moreover, the industry has until recently been among the most organically oriented in the nation. Olive trees in California have historically enjoyed a relatively pest-free existence. Chemical treatments have rarely been needed.


But the arrival of the fly changed all that.

About a quarter-inch long with a yellowish head and clear wings featuring a dark spot, the olive fruit fly bores into the tiny fruit, depositing its larvae. As they grow, the larvae consume the meat of the olive before emerging as mature flies.

Farmers have tried the single brand of pesticide approved for use on olive trees with some success. They also placed traps in trees featuring a mix of bait and fly killer. And they’re eyeing a clay-based spray that coats the olives with a smudgy layer, making them less inviting to the pest. One potential downside: Growers worry that they might not be able to find easy and economical ways to rinse the dirty layer off the olives.

In Europe, where the olive fruit fly dates back 2,000 years in historical records, the pest has a firm hold. When an infestation hits, farmers in big olive-producing nations such as Spain and Italy counter by spraying powerful chemicals allowed under their looser pesticide rules. Even then, infestations can claim more than 10% of a crop.


California growers wince at the thought of losing even 1% of their crop. With no sure-fire way of detecting fruit that is infested, a maggot-filled olive could occasionally find its way into a can, a quick way to lose the even most avid olive aficionado.

“If they start rejecting loads, then it won’t be very long before you’d be out of business,” said Erickson, who farms 200 acres of table olives near Orland, a tiny town west of Chico. “It could be the end of our industry.”

Though the pest doesn’t infest the trees themselves, just the fruit, only a season or two of squandered harvests would shut down the last two olive canneries in California, industry officials say.

So far, most groves in the Central Valley have avoided intense infestations. Growers say it’s unclear if that is because of the valley’s hot summers and cold winters.


But it’s a different story on the coast, where the mild climate acts as the perfect incubator.

Nick Sciabica, a third-generation olive producer, normally picks from trees in Santa Clara County that line freeway medians and backyards around the region. This year, he couldn’t touch them because of the level of infestation. The same went for crops he normally takes in from San Diego County and Los Angeles.

The Napa County wine region, home to some of the state’s new gourmet olive oil producers, could prove a particularly juicy target for the fly, Sciabica said. An infestation could taint the olive oil, pushing gourmet brands off the shelf.

“I’m getting near to hysterical worried,” Sciabica said. “It could be we’re just not going to be able to pick olives this year. I think we’re heading for either a partial or a 100% disaster.”


As they continue to fight the pest, farmers see one way the public can help, particularly in Southern California.

The Southland is home to tens of thousands of ornamental olive trees, some dating back to Spanish mission days. Those lovely, gnarled-bark trees produce fruit that can host an army of flies to power continual incursions into farm regions.

“There’s this reservoir of fruit flies that never goes away,” Erickson said. “They just keep coming over from the coast.”

Olive farmers are calling on residents to help reduce such problems by preventing the appearance of the fruit. It can be done simply enough, either by applying a special spray or using a garden hose to wash off blossoms during springtime.


In the farm country, officials are laying plans to more effectively wage war. Several counties, including Tulare, Glenn and Tehama, are expected in the next few months to launch pest-control districts specifically aimed at the olive fruit fly. The districts can take aggressive steps, from uprooting infested trees to spraying, paying for it with assessments on olive growers.

Minyard of the state Agriculture Department says such steps can help keep the pest in check.

“The industry is going to have to adapt to it,” he said. “It’s going to change the way everybody does business, no question about it.”