Experts Split on Outcome of Battle to Beat Medfly : Infestation: Most specialists approve of the county’s attack so far. They differ sharply, however, when it comes to predicting results.

Fruit will be quarantined. Fields will be sprayed. Flies will be trapped.

But will Ventura County ever be rid of the dreaded Medfly?

That question has sent bug experts from across the state buzzing to their file cabinets as they root through case histories from the past 15 years in search of battle plans and clues about the future.

Most Medfly specialists approve of the county’s attack so far--the intensive trapping efforts, the quarantine on fruit grown near the infestation, the plans for aerial spraying of the pesticide malathion. They differ sharply, however, when it comes to predicting results.

Optimists believe Ventura County will slide out of the crisis quickly, with minimal damage, by killing every last Mediterranean fruit fly in the next half year.

“I am confident that we (can) achieve eradication,” said Douglas Hendrix, spokesman for a joint state and federal task force charged with battling the Medfly.

With prompt action, “Ventura County will be in and out of this infestation rather quickly,” agreed Greg Van Wassenhove, agricultural commissioner for Santa Clara County, who said he has seen eradication programs “work very well here. The Medfly is something we can deal with.”

Bleakly, other experts dismiss such bullish assurances.

In their grim view, Ventura County is doomed to suffer wave after wave of infestation during the next few decades. This devastating cycle could ultimately crush the county’s agricultural industry, worth $848 million in crop sales alone.

“Of all the counties that have been infested, there has never, never, never been one that was dis-infested,” warns Jim Carey, a professor of entomology at the University of California at Davis.

“This is a creeping fungus that continually moves to expand its range, yard by yard, property by property,” Carey said. “It’s a cancer.”

Farmers, scientists, environmentalists and bureaucrats have all studied the Medfly since its first appearance in Southern California in 1975. They have tracked the blue-eyed pests from feast to feast, battling the fruit-gobbling insects along a trail stretching from Santa Clara to San Diego.

*

For all their research, they have failed to reach consensus on three key questions:

How does the Medfly flit from county to county?

How well do eradication programs work?

And how can bug zappers vanquish the voracious insects without harming the people who live nearby?

Spot eradication programs have won praise in half a dozen counties. A combination of quarantines, aerial and ground spraying, and the release of sterilized Medflies winnows the pest population dramatically--for a time.

But as soon as state officials declare, triumphantly, that they have achieved “eradication,” the Medfly crops up again elsewhere. Like the plastic gophers in county fair games, which sink under a hammer blow to the head and then pop up grinning in an adjacent hole, the Medfly seems invincible.

In the summer of 1990, for example, officials said they had succeeded in banishing the voracious pest from Southern California. Just one year later, a pregnant Medfly was discovered in a peach tree near Koreatown in Los Angeles. An intensive trapping effort uncovered 200 more Medflies in the area by 1992.

The Medfly’s uncanny survival skill taunts activists like Lisabeth Hush, who suffered eye irritation, accelerated heartbeat and other symptoms during the 1989 malathion spraying over the Los Angeles Basin.

Hush believes that the government’s Medfly policies do not work. And she considers the ballyhooed eradication plans more show than substance. The spraying may prove to Japanese trading partners that California is tough on pests, she says, but it does not conquer the Medfly.

“There is no entomology in California,” Hush said. “It’s all based on politics.”

*

State and federal officials bristle at such charges. They insist that they can--and do--eradicate the Medfly.

The problem, they say, is that the Medfly is constantly reintroduced, despite the strict quarantines. Tourists may smuggle in maggot-ridden tomatoes from Central America. Hawaiians may send fly-infested papayas to their relatives in Los Angeles.

And that’s all it takes.

Within months, the fast-breeding critters can produce enough offspring to spark another Medfly crisis.

“Nothing makes me madder than people bringing fruit back from Hawaii,” said Deena Gerry, whose family has tended a citrus grove near Camarillo since the 1930s.

Her son, Will Gerry, added: “People pick up mangoes in Hawaii, stuff them into their suitcases, and then when they get home and open them they say, ‘Eeew, look at these bugs!’ and throw them in the trash.”

Unless infested produce is double-bagged, sealed and placed in covered containers, the maggots can crawl out and begin breeding.

Both the state and the federal governments try to prevent such accidental infestations by policing quarantine boundaries to be sure no one illegally transports fruit from a Medfly zone.

Fruit-sniffing beagles at Los Angeles International Airport and the Port of Long Beach inspect baggage in an effort to root out contraband and enforce the 1,500-square-mile quarantine zone that spans four counties in the Los Angeles Basin. In the past, federal officials have even launched sting operations at local post offices to check for fruit smuggled in parcels.

*

Far from such traditional ports of entry, Ventura County’s quarantine covers 86 square miles surrounding “ground zero”--the low-slung fig tree on the grounds of St. John’s Seminary in Camarillo where the first two Medflies were discovered Sept. 29. Most crops within the zone, including citrus and avocados, must be treated before shipment.

A similar quarantine, combined with aggressive aerial spraying, squashed the Medfly threat in just six months in Riverside County earlier this year.

And although the quarantine caused some penny-pinching, farmers bounced back remarkably well. Drawing on their experiences, they now seek to reassure Ventura County’s growers.

“We were much more concerned than we needed to be,” Riverside County farmer Charles Colladay said.

About half of Colladay’s 2,000-acre ranch landed in the quarantine zone, which radiated from the city of Corona. He was able to treat the quarantined produce with malathion for about $60 an acre--a price tag which covered five applications of the pesticide, timed to kill each emerging generation.

“It was a scary thing when we went into it . . . but things just went like clockwork,” Colladay said. A firm believer that Medflies can be conquered, Colladay praised the state’s eradication program with a simple endorsement: “It works.”

But the Riverside method--eight aerial sprays, separated by six to 10 days--remains highly controversial. Environmentalists and city officials raised a ruckus in Corona, even going to court in an unsuccessful attempt to block the malathion sprays.

*

Noel Otten, research director for the Burbank-based anti-spraying group Action Now, said he believes bureaucrats “have an agenda to falsely reassure the public about malathion.”

A brace of scientific studies, though, backs the official word that malathion is safe.

A common back-yard pesticide, malathion does not cause cancer or birth defects and poses “no significant health hazard,” according to the state Department of Health.

It does, however, carry a significant price tag.

The Cooperative Medfly Project, a task force funded by state and federal tax dollars, spent $100 million from 1980 to 1982 to wipe out the Medfly in Santa Clara County. The group revived the same strategy seven years later to battle Medflies in the Los Angeles Basin, at a cost of $65 million.

Although the aerial spraying was declared effective in 1990, the Medflies popped up again just a year later. This time, political opposition blocked the aerial application of malathion bait, a potent substance that tricks adult insects into drinking poison by lacing the pesticide with sweet corn syrup

Without aerial sprays, the latest Los Angeles Basin eradication effort relies on the release of more than 400 million sterile Medflies each week. Officials hope the sterile insects will mate with fertile Medflies in fruitless couplings that will thin the ranks of future generations.

The sterile fly program, plus routine trapping and quarantine enforcement, cost $26 million last year. And it seems to be working--the number of flies found in the Los Angeles Basin has plummeted, from about 400 last year to just seven so far this year.

*

“Everything seems to have calmed down a lot because of the sterile fly releases,” said Bob Wyatt, legislative director for the Orange County Farm Bureau.

But sterile fly labs in Hawaii and Guatemala are working at full capacity to meet demands for the Los Angeles Basin. And state officials have expressed doubt that any sterile flies will be available for Ventura County.

Frustrated by such roadblocks, entomologist Carey has called for an “AIDS-like research program to come up with a long-term approach to dealing with the Medfly problem.”

While most agricultural officials continue to hope that the Medfly can be wiped out with spot eradication efforts, Carey insists that the pest has become firmly established in Southern California. He forecasts continual, costly battles against the pest--battles that could sink some farmers and trigger a much-feared Asian boycott of California produce.

“This Ventura County find is absolutely predictable,” he said. “We’re lurching from outbreak to outbreak here. . . . We have got to develop and implement a major research program to supplement our brush-fire approach.

“This thing isn’t the flu; it’s a cancer. So we can’t just treat the symptoms--we have to go after the disease itself.”

Southern California Invasion

Ventura County’s Medfly infestation follows a steady incursion of the fruit-devouring pest into Los Angeles, Orange and San Bernardino counties for nearly two decades. Here are capture sites by year. (graphic)

Source: James Carey, Professor of Entomology, UC Davis

Increasing Numbers

Adult Medflies captured in Southern California

1975: 77

1980: 5

1981: 53

1982: 1

1984: 1

1986: 1

1987: 45

1988: 54

1989: 235

1990: 44

1991: 25

1992: 195

1993: 399

Source: James Carey, Professor of Entomology, UC Davis

Aerial Spraying

WHERE: A 16-square-mile area of eastern Camarillo roughly bounded by California 118 to the north and the Ventura Freeway to the south.

WHEN: Beginning at 9 p.m. Wednesday and continuing three to four hours, and recurring once every two weeks for about six months.

WHAT: The pesticide malathion mixed with corn syrup to attract Medflies.

PRECAUTIONS: Stay out of the spray, especially the ill, very young and elderly. Cover shallow ponds and wading pools. Wash lawn furniture and playground equipment before using. Cover vehicles to prevent damage to paint.