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03.12.08

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Photograph by Steve Hahn
Bugged: The necessity of keeping the light brown apple moth out of Live Earth Farm means more work and expense for owner Tom Broz (left) and tractor driver Juan Morales.

Invasive Procedures

The moth crisis in Santa Cruz and elsewhere prompts experts to ask: does it make sense to try to wipe out exotic pests in an era of globalization?

By Steve Hahn


The dust swirls around Watsonville farmer Tom Broz as he surveys the empty field that will soon be sprouting Live Earth Farm's famously juicy tomatoes. In a few months he'll go through the annual ritual of hanging twist-ties drenched with pheromones around his farm to disrupt the mating of the codling moth. The ritual requires money, labor and time--three things not in excess at Broz's small organic operation. Yet for Broz, controlling pests like the codling moth is just "the name of the game" when it comes to environmentally sensitive agriculture.

Now that the light brown apple moth (LBAM) is also in the area, Broz will likely have to pencil in yet another round of twist-tie-hanging at a cost of about $120 per acre. But it's not that simple. Since both state and federal government have determined that the LBAM must be eradicated, Broz has more than just the cost of twist-ties to worry about. The feds are inspecting his orchards every month, and if they find even a single sign of the moth, he could be shut down until the inspectors are satisfied that his farm has been rid of it for good.

"Imagine if I lose one week of produce because I'm being quarantined in the middle of the season. That could add up to $20,000 or $30,000 right there," notes Broz. "So controlling something preventatively beforehand ends up costing almost nothing compared to being shut down because there is one egg on the underside of a single leaf in my orchard."

Broz isn't the only one calling into question the government's plan to eradicate the LBAM rather than simply control it. Over the past six months, well-respected Ph.D.-wielding entomologists and horticulturalists have expressed increasing skepticism at the scientific basis of the eradication plan. In the course of the debate, wider questions about how to confront invasive pests in an interconnected world have also surfaced.

Behind the Curtain
Dr. Marshall Johnson wiped the sweat from his brow as the sun beat down on the pavement in front of San Jose's Wyndham Hotel. Making his way through the lobby, Johnson headed straight for the conference room where a group of insect buffs were already furiously skimming through reams of biological information on a newly discovered pest from Australia, the light brown apple moth.

It was May 2007, and the 10 assembled entomology experts, at least half of whom were on the United States Department of Agriculture's payroll, felt a heavy weight on their shoulders. They had been hastily called together, given the label Technical Working Group (TWG) and tasked with determining whether or not the federal government should declare total war on the LBAM and begin a multistage process of wiping it out. If they decided it was too late and that the pest had become firmly established on the U.S. mainland, they would have to recommend the eradication fight be given up and management pursued instead.

A lot was at stake. The moth was spread across five counties, from Monterey to the Bay Area, but hadn't yet hit the Central Valley, the heart of California's agriculture industry. Farming groups and foreign trading partners were already clamoring for the feds to wipe the pest off the face of the continent. The TWG scientists were presented with figures from Australia, where it costs over $21 million a year to control the pest.

With this mass of information swirling in their heads, the members of the TWG were allowed only three days to make their final recommendation. None of the scientists at the time could have guessed how much controversy their decision to pursue the goal of total eradication would generate, nor could they have predicted the much broader questions about invasive pest policy that would arise as public support for the fight against the pest deteriorated rapidly.

Moth Code Red
Anti-spraying activists have frequently targeted the California Department of Food and Agriculture (CDFA) as the agency responsible for the blanket spraying of homes and schools, but it was actually USDA's Animal and Plant Health Inspection Service that originally sounded the alarm and convened the TWG when it heard the LBAM had been found in California. The feds wanted action fast. They had on their desks a report produced in 2003 by University of Minnesota entomologists suggesting the moth could infest up to 80 percent of the continental United States. This made the LBAM infestation an extreme threat in their minds, both to the native environment and to the nation's economic interests. The pressure was on the CDFA to act swiftly. If the state lagged behind, the USDA reserved the right to quarantine all of California, according to a University of California Integrated Pest Management report.It was under these tense circumstances that Johnson, an award-winning veteran entomologist from UC-Riverside, was called to San Jose to talk LBAM. He remembers the three-day conference like it was yesterday.

"When we first went into the group, the assumption was that there would probably be eradication because it was a new pest," he remembers. "It wasn't a big argument or anything like that; it was a discussion of what we know, what we don't know and what the probability was that this could be accomplished. It was a very short discussion."This discussion, however short, yielded four compelling reasons for eradication, according to Johnson. First was the issue of economic impact.

The USDA was predicting crop damage that could cost growers anywhere from $160 million to $640 million dollars annually, and that was just for the counties already infested. If the LBAM spread to other states, USDA was predicting that the cost of crop damage could reach the billions.

That wasn't the whole story, though. There was also a great deal of fear that the pest could shut down California's ability to ship agricultural goods out of the country. It was an ironic series of events: For reasons that aren't clear, the LBAM was classified as a "Class A" pest by the CDFA in 1996 (it is not clear whether USDA listed the pest on its watch list as well, but the feds were nervous enough to order up a report on it in 2003). Under this CDFA designation, which is the highest possible under state law, shipments of agricultural commodities from New Zealand and Australia had to be inspected thoroughly for LBAM before they were allowed access to California ports. This meant growers in New Zealand and Australia had to spend extra money and time proving their products were LBAM-free in order to ship their agricultural commodities to California.

When the pest was discovered on the U.S. mainland, the A-rating came back to haunt the CDFA and shake the nerves of USDA officials. Canada and Mexico began requiring thorough inspections of all produce for LBAM before it was shipped across their borders, and at least seven states were calling for advanced warning whenever shipments from the infested counties were heading their way. Although LBAM hadn't damaged any crops yet, it was evident the moth was going to end up costing growers across the state millions in lost sales and control efforts. This costly reality was on the minds of all TWG members, says Johnson.

"The driving factor is the possibility of other countries shutting off our exports to them," says Johnson. "If you went from eradication to management, you would have to be at zero tolerance for export." As for local growers selling their products within an infested county, Johnson predicts they would only use pesticides and other control methods if the cost could be passed on to the consumer, meaning either higher fruit prices at the market or large losses for growers who would have to throw away damaged products.

This would be an expensive long-term proposition for growers, and, to make matters worse, it wouldn't be concentrated in a single agricultural industry. The pest could infest up to 250 different plants, including most fruit trees and decorative plants sold in nurseries. There were also reports that the LBAM had the ability to incorporate new plants into its diet over time, meaning it could potentially threaten all of California's agriculture fields, and possibly over 75 percent of fields in the United States. Mysteriously, no crop damage had been reported. Nevertheless, the TWG chose caution.

"Since the light brown apple moth already has a broad range of plants it eats, it makes it a lot easier to adapt to new plant species," says Johnson. "The main ecological ramification would be its ability to invade new areas in California or the United States, and once it started to take off in places like the San Joaquin Valley, where you have peaches, olives and nectarines, you might have to start spraying [toxic] stuff for it."

Regardless of how far the moth has spread thus far, Johnson and others worry that if management were pursued instead of eradication, individual growers would eventually decide to defend their crops with toxic pesticides. That could cause a huge problem, says Johnson. Not only does the LBAM adapt to new plant hosts as it spreads across the world, it has also shown the ability to evolve pesticide resistance. This was observed most notably during its infestation of New Zealand, says Johnson.

"If you get a lot of people who start spraying for it, and then it develops resistance, people will have to start spraying more toxic pesticides more frequently. You don't know what the ramifications are for the management system of other pests."

Not to mention the ramifications for the state's water supply and any animals or humans exposed to the toxins.With the severity of these four key threats in mind--export restrictions, the pest's adaptability, the potential spraying of toxic pesticides by individual growers and a fear that the pest could develop pesticide resistance--the TWG concluded eradication must be pursued swiftly. In short order the pieces began falling into place: An emergency environmental review exemption was granted by the Environmental Protection Agency for use of the Checkmate-LBAM pheromone, a substance that would release the female moth scent over a large area and thus hinder the male moth's ability to find a real female mate; federal and state quarantines were established in all infested counties and nurseries were forced to spray the organophosphate chlorpyrifos on all their products if even a single moth adult or larvae was found.

The Other Shoe Drops
In September, fewer than five months after the TWG had made its recommendation, three planes were dispatched to release pheromones over Monterey County. In November they sprayed Santa Cruz County. Immediately a chorus of environmental and public health groups decried the blanket spraying of pheromones over houses, schools and places of business. Newspaper articles reporting on the CDFA's handling of the pest were pouring forth, as were lawsuits attempting to stop the spraying (four in total).

Hastily organized anti-spraying citizen groups called on Assemblyman John Laird and state Sen. Joe Simitian to stop the spraying. Amid this troubling backdrop, respected entomologists and others began to question whether or not the state's eradication goal was really possible. Dr. James Carey, a UC-Davis entomologist who has been writing research papers in the field of pest management for over 20 years, believes it is nothing short of wishful thinking to suppose a pest that has now infested at least nine counties can be eradicated.

"It's not that I don't favor eradication. I'd like to get rid of it if we could do it easily. That's not the question. It's a matter of what I see being a program that's been launched that has no chance of success," says Carey. "I seriously doubt that they've really delineated the population. There are literally tens of thousands, if not hundreds of thousands, of populations of LBAM, so anything less than 100 percent elimination of every one of these tens of thousands of individual populations is control and not eradication."

Carey knows whereof he speaks. He provided research that has helped the CDFA keep the Mediterranean fruit fly under control (the Medfly has successfully resisted eradication all along) and has published well over 50 essays on pest management. According to his experience, a perfect mix of biological and political factors needs to be in place before a pest can realistically be eradicated. He doesn't think these preconditions exist with LBAM.

"You need an effective tool. We don't have it here," says Carey. "You need public support. It's not clear that we have that here. You need a detection tool that is effective even in the advanced stages of eradication so you can identify pockets, but also in the early stages so you can delineate a population. Lastly, you need long-term funding. You can't have a program set in motion and then at the whims of an administration have the program pulled."

As cracks in the scientific consensus began to threaten the foundation of legitimacy TWG members had given the the CDFA, critics from the nursery industry also became more vocal. Since LBAM was discovered in Santa Cruz County last year, government inspectors have been showing up at every Santa Cruz County nursery that ships products across state lines every two weeks. If any sign of the pest is found, the entire nursery is shut down so pesticides can be sprayed and the nursery reinspected.

This hasn't been sitting well with some local nursery owners, or the officials charged with representing them. Dave Cavanaugh is the director of the ornamental horticulture program for the Santa Cruz County Farm Bureau. He worries that pressure from trading partners has caused the CDFA and the USDA to rush into an eradication program without properly researching the pest's biology first.

"I don't think the data is there to support whether it should be eradicated, nor whether it should not be eradicated," argues Cavanaugh. "Because we don't have the biological assessment, all we're doing is throwing a lot of money and energy after this insect. It may not be the problem they say it is, or it may be a lot worse. I just don't have the information to say."

According to Johnson, the TWG had recommended to the CDFA back in May that it evaluate different crops the moth might eat to see which ones would be most severely impacted by LBAM feeding. Johnson said he hasn't heard of that process going forward, and Steve Lyle from the CDFA said he couldn't track down any information on these efforts.

Threat Overblown
Another voice joined the call for management on March 7, when UCSC Arboretum director Dan Harder finally released a report on his research trip to New Zealand. He had toured the northern part of the country, which he claims has a similar climate to the Central California coast, and found that controlling the pest could be cheap, easy and effective.

The trick, according to the 11 sources he cites in his report, is to hit the moth colonies with a one-two punch: First, release the natural predators. According to Harder's retelling of an interview with a Dr. Peter Shaw of New Zealand HortResearch, about 80 percent to 90 percent of moth larvae are knocked off by these LBAM-killers. They include a number of different wasps, flies and even the notoriously deadly earwig. As for the remaining 10 percent to 20 percent of LBAM larvae that survive, Harder cites HortResearch reports that recommend using "insect birth control," also known as Insect Growth Regulators. These sprays don't kill the larvae, but instead prevent them from blossoming into adults, meaning they can never reproduce.New Zealanders adopted this two-weapon approach in 2001, after the use of organophosphates between the mid-'90s and 2001 killed off the moth's natural enemies, resulting in exploding LBAM populations.

Back on this side of the pond, Cavanaugh sees CDFA and USDA officials, who he is quick to mention are "doing the best they can given the circumstances," as being forced to pursue eradication so they can appease trading partners, even as serious questions about the feasibility of eradication are left unanswered.

"It's like when the bubonic plague hit in Europe," Cavanaugh says. "People were going around burning down houses and burning people alive because they didn't know what they were dealing with. Once they found out it was carried by a flea, it was treated appropriately. It's the same thing here; they don't have the information ahead of time, so they're effectively experimenting."

It may be an experiment and maybe it won't work, but given what is at stake, eradication should be pursued anyhow. This is the thrust of retired UC-Davis Entomology Professor Dick Rice's argument. Eradication is never easy, says Rice, but if we just "throw up our hands" and admit defeat before the fight has even begun, there could be devastating consequences.

"Eradication in the coastal areas is going to be difficult because over the winter and early spring, before CDFA and USDA start their pheromone program, this pest is going to be spreading into uncultivated areas, not just orchards and agriculture fields," Rice says. "But it's still something to attempt if they can afford to do it and show some success. My thinking is that if LBAM did become established ... up into Oregon and Washington, it would increase expenses tremendously both in terms of ornamental industry and the tree-fruit industry."

Yet Cavanaugh and other critics of the eradication plan point, yet again, to the fact that there has been no recorded damage to California agriculture.

"So the basic question is: Are we overreacting to exotic pests on pure speculation?" asks Cavanaugh.

Ticket to Ride
The eruption of controversy over USDA and CDFA's eradication goal and the subsequent treatment plan may be just a hint of things to come. In an era of global trade, the opportunities for pests to catch a free ride across the ocean become so ubiquitous no government can realistically plug all the holes in their borders.

A report from the United Nations' Food and Agriculture Organization provides a glimpse into this stark reality. In just one year, from 2004 to 2005, worldwide food exports increased 8 percent. Between 2000 and 2005, the figure was 23 percent. There is little doubt this process will become much more pronounced as the worldwide population increases to more than 8 billion people by 2030 and trade balances between countries continue to deepen. It's not just agricultural goods either. Wood packaging, foreign tourists and the ballast water of ships can all easily spread invasive species. As long as consumer goods are produced in China, coffee is shipped to United States ports from South America and summer vacations are spent in the tropics, pests will be transported to and fro.

Dr. Ann Bartuska has been following this troubling trend for over a decade. She was one of the founding members of the Nature Conservancy's Invasive Species Team in the late '90s and now works as a researcher with the USDA Forest Service, where about 20 percent of her work week is spent dealing with invasive species. She believes that if prevention fails, eradication is critical.

"We've spent a lot of time in the past on control and management of established organisms. But you lose the battle that way," says Bartuska, who is not familiar with the particulars of the LBAM situation. "Recognizing that you don't get everything [with prevention], you should have an early detection and rapid response and eradication effort."

For Bartuska and other environmentalists, this is less an economic issue than an environmental one. As fragile ecosystems suffer under the weight of human activity and climate change, an invasion by pests with no natural enemies in the area can mean extinction for many native species. Dr. John Randall, who works at UC-Davis and runs the Nature Conservancy's Invasive Species Team, believes this is a huge threat to biodiversity that must be combated first with prevention, but then with swift eradication plans when dangerous new pests are discovered.

"These pests change the character of our natural environments. It's one more threat to an already beleaguered and limited area of wild vegetation and native species," says Randall, who is also unfamiliar with the specific situation of LBAM. "If you're able to identify, contain and eradicate a pest early, the number of pests in the area you have to treat is small and the costs are far smaller. It has been shown over and over again that the state and society spends far less with that kind of approach.

"So perhaps rushing forward with eradication plans even as comprehensive biological research lags behind is wise both for the nation's food supply and environmental health. Not so, argues Carey.

"CDFA and USDA right now just basically draw a bull's-eye and say, 'Kill!' It's not sophisticated at all," says Carey. "The science needs to be coherent with the operational aspects. The agencies in academia need to work more closely on this. Right now, and I'm trying to change this, UC is really not involved at all even though we're the research arm of the state. CDFA, industry and academia all need to be on the same page here."

Bartuska and Randall both echo this call for increased communication between researchers and policy makers. However, Randall believes this is only one of the many improvements that will need to be made as invasive species find almost daily opportunities to spread in an increasingly interdependent world.

"What we have now is not good enough nationally or internationally," says Randall. "The bad news is that funding was cut to CDFA in 2000 and has still not completely been restored. This has hurt the state Department of Agriculture's ability to keep out pests."

How the world deals with the invasive pest threat is yet to be seen, but work has already started on finding solutions, both within government and among conservation groups. Whether or not these solutions will be enough to overcome the formidable challenges invasive pests will pose this next century is an open question, even for experts such as Rice.

"We're going to continue to see more of these invasive species come in, and we've known this for years." says Rice. "This will be particularly true as we get into more of these trade agreements with other countries and the ability to ship things without really high levels of inspection and certification becomes commonplace. It's going to get much more difficult. I see a lot more of this stuff coming down the road."

A Bug's Life

It was a balmy summer morning when bug fanatic Jerry Powell wiped the sleep from his eyes to discover he had attracted an unusual friend to his Berkeley back yard. The small moth was circling an ultraviolet light the retired entomologist had set up to continue his lifelong bug-watching passion. But the visitor on this morning in July 2006 was markedly different from Powell's usual insectoid guests. This one, the light brown apple moth, was a native of Australia and had never before been seen in the United States.

Powell eventually alerted the California Department of Food and Agriculture, which sent over inspectors on Feb. 9, 2007. The inspectors set up traps around Powell's home and sent the captured specimens along to a CDFA lab. Two weeks later the results came back positive. The LBAM was in California, and state agriculture officials were scared stiff. The moth could potentially eat many of the state's high-value crops and maybe even damage native trees by rolling up and eating leaves. To find out how far the moth had spread, they set up pheromone-baited traps in various locations throughout the East Bay in March. Only 77 moths showed up. So far, it didn't look like a huge problem. But a surprise was on the way.

In April, CDFA officials decided to set up traps farther south, just to be safe. They were astonished when hundreds of samples from Santa Cruz County began pouring in. By mid-April more than 1,000 moths had been collected from the county, and state agriculture officials were getting very nervous. They decided to impose strict quarantines on nursery products coming out of all five infested counties and called together a technical working group to decide how best to eradicate the pest. The Watsonville Fairgrounds became the command center for CDFA inspectors, and local nurseries began receiving surprise visits.

Small populations found in Napa and Los Angeles were eradicated using the larvae-eating bacteria BT in the summer of 2007. By the end of the year, the quarantine had expanded to nine counties. In mid-January, CDFA released its eradication plan for the year. It would involve aerial application of pheromones in the five most heavily infested counties--Santa Cruz, Monterey, San Francisco, Alameda and Contra Costa--and ground applications of pheromone-drenched twist ties, BT and spinosad in the other four counties (Santa Clara, San Mateo, Marin and Solano). An attract-and-kill mix of pheromones and pesticides would also be applied to telephone poles in all infested counties. Predatory stingerless wasps would be released in Santa Cruz, San Francisco and Monterey counties.

By now, the aerial portion of the eradication plan has been thoroughly assaulted, and as lawsuits and bills circulate to stop the aerial spraying, it is unclear whether the pest will spread beyond the ability of the CDFA to effectively eradicate it.

Steve Hahn

Curing The Cure

Environmental and public health activists have been beating down the doors of Bay Area legislators in Sacramento for the past three months, demanding they stand up to the CDFA as the agency powers forward with plans to aerially spray four counties with a synthetic pheromone to battle the LBAM. The legislators have apparently been listening. On Friday, Feb. 22, a set of four bills related to the CDFA's handling of the infestation surfaced in the state Assembly. A.B. 2760, written by San Francisco Assemblyman Mark Leno, would halt the aerial spraying, currently slated to begin on June 1, until the CDFA has drafted an Environmental Impact Report (EIR). The EIR is still in the early stages; it would likely take well past June to be finalized. Under state law, an EIR is normally required before spraying pesticides, but an emergency exception was granted by the federal Environmental Protection Agency last year.

Marin County Assemblyman Jared Huffman wants to force pesticide manufacturers to release information on all the ingredients contained in their products before they're used by any state agency, emergency or no. A.B. 2765 comes in the wake of pheromone manufacturer Suterra LLC's refusal to disclose the ingredients in Checkmate LBAM-F, citing its right to protect the information from potential competitors.

Rounding out the challenges to the emergency declaration issue, A.B. 2764, introduced by East Bay Assemblywoman Loni Hancock, would make the governor the only public official who could proclaim a state of emergency requiring the spraying of pesticides over urban areas.

While these three bills respond to the loud accusations that the CDFA has ignored public concerns and plowed ahead with an eradication plan that puts human health at risk, at least one lawmaker is focusing on the overlooked issue of invasive pest planning. A.B. 2763, introduced by Santa Cruz Assemblyman John Laird, would require the CDFA to compile a list of all the invasive pests that could potentially harm California's agricultural interests. CDFA staff would then be required to identify which pests the state would plan on eradicating if found in California, how the eradication plan would be carried out and which pesticides or pheromones would be used in each eradication plan.

Steve Hahn


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