Jury Still out on Pesticide Substitute Trials

The future of Ventura County’s $176-million strawberry industry may lie in a remote corner of an Oxnard ranch.

There, as part of an experimental program, ranch manager David Murray is trying to find a replacement for the potent but controversial pest killer methyl bromide.

“We’re going to lose methyl bromide, we all know that, but our company wants to be on the cutting edge of finding alternatives,” said Murray, general manager at Coastal Berry Co., where worm droppings and a cornmeal byproduct are among the methods being used this season to control insects, weeds and diseases.

“I think most growers out there to some capacity are trying different alternatives,” Murray added. “I think they figure if they wait until the last minute to find something, they’re going to miss the boat.”

Confronted with the phaseout over the next five years of the world’s most popular fumigant, Murray is among two dozen strawberry growers statewide taking part in government-funded trials to find alternatives for the pesticide, which is being eliminated because it is highly toxic and depletes the Earth’s ozone layer.

It is a race against time.

Under the terms of an international treaty, methyl bromide production is to be reduced 25% this year, 50% in 2001, 70% in 2003 and banned altogether in 2005.

Growers of about 70 California crops inject the colorless, odorless gas into the soil to cleanse it of insects, mites, rodents and weeds before planting.

The pesticide is especially popular in the strawberry industry, where it is used on more than 90% of the commercial acreage in California.

But despite years of government and university trials, researchers have yet to find anything as effective, cost-efficient and widely available as methyl bromide. In fact, it’s likely that growers will need to employ a veritable cocktail of other chemicals and organic compounds to match the efficacy of the ill-fated pesticide.

And in California’s fast-growing strawberry industry, that has plenty of growers worried about the future of their valuable cash crop.

“I think there is a bit of urgency out there,” said UC Davis professor John Duniway, who is heading the statewide strawberry field trials in conjunction with the California Strawberry Commission and the U.S. Department of Agriculture.

“There is nothing that works as well in terms of having the consistency and reliability,” Duniway said. “I think we’ve been able to show that there are some alternatives that can work, but I think growers are worried about how it will all work out in the long run.”

Economic Losses

By some measures, potential economic losses could be staggering.

The National Center for Food and Agricultural Policy estimates annual losses of as much as $450 million for U.S. producers of crops treated with methyl bromide.

Those losses would hit California and Florida growers hardest. And in California, the strawberry industry would be hit hardest of all.

One survey predicts a potential 10% loss in strawberry production the first year without methyl bromide, 20% the second year and 30% to 40% in subsequent years due to the buildup of soil-borne diseases.

The USDA puts the potential net impact to the strawberry industry at $131.5 million a year, losses that will persist until more effective and cost-efficient alternatives are found.

At a time when local growers have planted a record number of acres--there are 7,500 acres in production this season, a 12% increase over last year and a 68% increase over the past five years--the search for alternatives is a hot topic of discussion in the agricultural community.

“It’s the first question I get everywhere I go,” said Frank Westerlund, the strawberry commission’s director of research. “Growers want to know what’s going to happen and where we are on the research.”

The USDA has a $14-million budget this year and 41 scientists dedicated to finding methyl bromide alternatives.

In addition, the federal agency has funneled $100,000 a year since 1996 into cooperative projects with the strawberry commission and the University of California.

While there is no single substitute for the pesticide, several chemicals in combination have shown promise. And the research has given the industry as a whole a better understanding of how the alternatives will fit into current farming practices.

Research Concerns

But for those who long fought to ban methyl bromide because of its high toxicity, there is growing concern about the amount of research focused on alternative chemicals rather than organically-based compounds that don’t endanger public health.

Locally, a coalition of environmentalists and farm-worker advocates have long pushed to restrict use of the fumigant, especially near homes and schools. But Lori Schiraga, program director for the Environmental Defense Center, said the public won’t benefit if one toxic pesticide is replaced by another.

Schiraga pointed out that one of the possible alternatives under review--the herbicide metam-sodium--caused the evacuation earlier this year of an elementary school in the agricultural community of New Cuyama in Santa Barbara County. Five school employees and 17 students were sickened when pesticide vapors drifted from an adjacent agricultural field.

“I would like to see the research shift a little more to nonchemical alternatives,” Schiraga said. “I can understand anyone being concerned about their livelihood, but at the same time I think growers need to be looking at alternatives that are not going to put them in the same place they already are.”

The search for alternatives has run a broad spectrum.

A number of chemical alternatives have been tried with varying results. Nonchemical trials have included everything from crop rotation to steam treatments to soil additives, such as in San Luis Obispo, where a strawberry grower is experimenting with an organic mix of broccoli residues and mushroom compost.

Research is also taking place at the front end of the growing season. Nurseries are producing vigorous, disease-free strawberry plants called plugs, which are grown in artificial potting mix instead of fumigated soil.

Lack of Availability

One problem researchers have encountered is that many of the potential substitutes for methyl bromide have not cleared regulatory hurdles and are not yet available to growers. Other chemical alternatives are registered for use, but are restricted in various ways.

California Strawberry Commission President David Riggs said growers need time to figure out how to use replacements effectively and efficiently before they can rely on them for their economic survival.

“Many of the chemical alternatives are really not even available at such a level that we can even start experimenting with them, so that for growers to put them down really becomes a high-stakes gamble,” Riggs said.

“Unfortunately, the process of getting new alternatives registered and available for use is a lot slower than the onrushing phaseout date.”

Truth is, methyl bromide was supposed to be phased out earlier than 2005.

Under the federal Clean Air Act, growers had been bracing for a mandatory cutoff in 2001. But many agricultural scientists argued that developing cost-effective alternatives required more time, and growers last year won a four-year reprieve from Congress. The postponement until 2005 conforms with an international deadline for developed nations under the so-called Montreal Protocol, an international treaty signed by more than 160 countries.

The federal Environmental Protection Agency is overseeing the phaseout. Ventura County Agricultural Commissioner Earl McPhail believes most local berry growers will curb their usage long before the deadline.

“My gut feeling here is that within the next year or two, most strawberry growers won’t be using it anyway because there won’t be enough available,” McPhail said. “There is some concern out there. But growers are a pretty resourceful bunch, they’ll do what they have to do to make sure they produce a good quality crop.”

That’s what David Murray is busy trying to do. This is the off-season in the strawberry industry, the period between planting and picking in which growers wait for their crops to turn from pale green buds to plump red berries.

Murray has participated in the USDA-funded trials since they were launched in 1996, testing a variety of alternative chemicals with varying degrees of success.

This season, he’s growing 2 1/2 acres of berries using the fumigant chloropicrin delivered through a drip irrigation system. On another 2 1/2 acres, he’s taking part in a trial with a private company using a combination of organic material--compost and cornmeal gluten--to strengthen the soil and help roots fight off disease.

The results are far from perfect. Murray said he can think of four or five things wrong with every alternative he has tried during the past three years.

Even now, he can already see weeds popping up on the experimental acreage that was planted earlier this month.

“You wouldn’t see that in a methyl bromide field,” said Murray, slogging through the muddy furrows that slice through his experimental plots.

“But our attitude has been we know there is going to be change, so we just have to deal with it,” he said. “If we’re going to lose it, and everybody else is going to lose it, all we can do is focus on finding something we can use.”