When the Montreal Protocol was passed in 1987, the international agreement formed a pact among countries all over the world to bring an end to the depletion of the ozone layer.

It promised that by the year 2000, chemicals harmful to the atmosphere — mainly from the displacement of crop pesticides — would diminish greatly in their usage. In the case of one perceived environmental nemesis, methyl bromide was to be phased out altogether by the turn of the millennium.

Fast forward to 2009: Ventura County strawberry production is at its apex and methyl bromide is still in use.

The question: What’s been taking so long to get rid of the reviled fumigant? One answer: It works.

“We’ve tried everything,” says Edgar Terry, a Ventura farmer and business professor at Cal Lutheran University. “The best material out there now to clean your soil is methyl bromide. There is no alternative that is as effective. In spite of what anyone says, it’s effective.”

Methyl bromide, or bromomethane, is a fumigant that in Ventura County is sprayed in soil to kill fungi intrusive to fruit and vegetable crops. It’s been cited as one of the reasons why production of strawberries countywide has nearly tripled in the last two decades.

“It’s pretty much at its historical peak,” says John Krist, CEO of the Ventura County Farm Bureau.

According to Krist, just 15 years ago Ventura County could account for a solid 4,000 acres of the beloved berry. Today, that number exceeds 12,000 acres, due in part to methyl bromide, killing every fungal invader in its path and allowing crops to thrive uninhibited with few, if any, complications.

But if there is such a thing as a necessary agricultural evil, it’s methyl bromide. Farmers are compelled to use the chemical to fumigate their crops, knowing full well that it contributes to atmospheric erosion — there is no similar, less environmentally harmful, yet effective, alternative. It’s one of the reasons why Federal Environmental Protection Agency has continuously granted extensions on the gradual phase-out of bromomethane, placing the industry almost 10 years past its 2000 methyl bromide-less due date.

“The deal on methyl bromide,” Krist said, “is it was phased out with the international agreement, but there have been exemptions made in areas where there’s critical use and there’s no substitute.”

Data from the California Strawberry Commission (CSC) indicates that per-acre usage of methyl bromide in California has decreased from 195 pounds per acre in 1992 to 130 per acre six years ago. Similarly, the use of alternative pesticides has seen an increase from 84 pounds to 156 pounds per acre, in the same time frame.

Methyl bromide is just one of several chemicals containing elements of smog-forming volatile organic compounds, or VOCs. The California Department of Pesticide Regulation current standards call for a gradual reduction of VOCs, which are emitted from crop soil fumigated with methyl bromide, on a tons-per-day basis.

By 2012, says Mike Villegas of the county air pollution control district, VOC use in Ventura County must be capped off to 3 tons per day. That figure represents a 20 percent reduction from 1990 baseline numbers of 3.8 tons per day, before strawberry crops saw massive increases in production and before methyl bromide use rose to an average of 4.8 tons of emissions per day in 2004.

“They’re going to have to reduce within 2011, 2012,” Villegas said.

Terry calls methyl bromide a “problematic substance” but acknowledges its current place in local farming practices until suitable alternatives are found.

“It’s a balancing act,” he says. “With berries, if they don’t fumigate, there aren’t many grounds in the county you can grow on. If the growers lose access to the tools that they need right now to grow profitably, there aren’t too many things they can switch to that generate that many returns …. (It) jeopardizes the economic underpinnings of the industry.”

In terms of affordability, reduction of methyl bromide use shouldn’t be a problem. It’s expensive to obtain and apply. According to Krist, it costs roughly $3,000 per acre to fumigate with the chemical once a year. Taking into account Ventura County’s current strawberry growing status, that’s $36 million annually for the entire region.

“Farmers don’t use it just for the heck of it. They have to determine the cost,” says Krist. “It’s something they put a lot of thought into before they use it.”

“A lot of it in Ventura County is driven by the fact that it’s so expensive to use the stuff, it’s becoming cost-prohibitive,” says Terry.

One cause for the delay in phasing out methyl bromide boils down, in part, to the local ag industry’s continued search for a viable alternative to methyl bromide, a search that, unfortunately, has been futile to this point. According to Terry, Krist and others, tests have been carried out with replacement fumigants, all of them safer, but none of them as potent and reliable as methyl bromide.

“The alternative fumigants aren’t as effective as methyl bromide in controlling certain problems,” says Oleg Daugovish, a strawberry and vegetable crop adviser for the University of California extension office in Ventura.

Those problems include the growth of invasive weeds that alternatives can’t control as well as methyl bromide. The same goes for soil pathogens. Deemed minor and unimportant with methyl bromide, they become a sticking point with other pesticides explored by researchers.

“Some types of fungus diseases that weren’t significant have shown themselves in fields,” says Krist. “It’s built up to a level that it takes the plant down in a number of ways.”

“We normally would never think of them in the methyl bromide days,” Daugovish says. “Now that we switch to other alternatives, they become major pathogens on a major scale. We’ll trade one problem for another.”

It’s been a costly endeavor for researchers, too. According to data from the California Strawberry Commission, it has, to date, spent more than $10 million to find a methyl bromide alternative.

For the growers, it could become a major problem if a long-term solution isn’t found soon. According to Terry, historically it was escalating land values that forced onetime moneymakers celery, lettuce, broccoli and cauliflower out of Ventura County.

“Strawberries have filled that void,” he said.

Krist says it was the crop that took the county by surprise.

“I don’t think people were thinking strawberries back in the ’90s,” he said.

If the best alternative fumigant, however, gives weaker results than does a methyl bromide, strawberry crops could suffer, losing their foothold as the county’s big, profitable ag leader. Two years ago, CSC valued county strawberry crops at more than $300 million.

“We hope it doesn’t come to that because there is no other crop to grow here,” Terry says.