KINGSBURG, Calif. — Even as farmers and chemical companies press the case for continued use of methyl bromide, a shift is already taking place in agriculture away from the deadly, ozone-depleting gas.
Alternatives to methyl bromide--the world's most popular fumigant, which kills insects, weeds and diseases on 118 crops--are now being used by a small but growing band of California farmers and shippers of fresh fruits and vegetables.
Since 1990 the yearly use of the chemical in California agriculture has ranged from 14 million to 18 million pounds. But farmers, soil fertility experts and university scientists say that while the use of methyl bromide on strawberries and table grapes has risen greatly since the 1980s, its use on a wide range of other crops has leveled off or decreased.
In Napa and Sonoma counties, for instance, many wine grape growers no longer apply the chemical when planting or replanting. To combat soil-borne pests and viruses, growers are now fallowing land for a year or two, planting cover crops and also looking to tolerant or resistant root stocks.
"Fifteen years ago, we wouldn't have thought twice about using methyl bromide when planting a new field," said Andy Bledsoe, director of wine grower relations and research for Robert Mondavi in the Napa Valley.
"Now we rarely, if ever, use it. The wine grape industry can live without methyl bromide."
Part of the shift is a recognition that methyl bromide faces both a national and international ban in the next five years, even if the state Legislature decides this week not to impose a March 30 ban in California.
But the change is also rooted in the growing acceptance of organic or sustainable farming techniques among longtime conventional growers of fruits and vegetables.
"I'm coming across more and more conventional farmers who are willing to change to a more environmentally friendly approach," said Darin Moon, a soil fertility consultant who is using a nontoxic alternative to methyl bromide.
"This is not just a change in chemicals. You're talking about a completely different philosophical approach to farming."
The colorless, odorless methyl bromide kills everything in its path. Whether it is strawberries along the hilly Monterey coast or table grapes here in the flat San Joaquin Valley, farmers who do not use the expensive gas face higher labor costs and lower yields.
"It's definitely harder to farm without it," said Jim Cochran, a Santa Cruz farmer who grows 45 acres of organic vegetables and strawberries overlooking the ocean. "I have 30 more problems to deal with that farmers who fumigate with methyl bromide don't have."
But life without methyl bromide, Cochran and others say, is not the disaster some farmers, chemical companies and politicians would have you believe. While their yields are 15% to 25% lower than conventional growers, they say they have found a way to make a profit while not endangering their workers or harming the environment.
And they point out that in the case of strawberries and table grapes--crops often in surplus that are the heaviest users of methyl bromide--a little less yield may not be such a bad thing.
"Shippers and packers encourage a surplus," said Dale Coke, who farms 250 acres of lettuce, broccoli and strawberries near Watsonville. "And methyl bromide is a tool to do that."
Salinas farmer Paul Kohatsu, a third-generation strawberry grower, is one of those who predicts economic catastrophe for himself and his neighbors when methyl bromide is banned. His grandfather was one of the first growers to use the chemical in the Santa Maria Valley a half-century ago, and it is as important today as it was then, Kohatsu says.
"It makes a night and day difference," he says. "The plant growing on soil fumigated with methyl bromide has six or seven big leaves. The plant without it has two or three."
He disputed estimates by the federal Department of Agriculture and others that yields will fall only 15%. "You're talking about a 40% drop, for sure," he said. "It's going to devastate the strawberry industry."
Fifteen years ago, methyl bromide was a vital part of the toxic arsenal that Joe Soghomonian used on his 470-acre vineyard in Fresno County. But as his children were growing up in the early 1980s, he began to doubt his chemical ways.
"The more you use, the more you have to use more," he said. "I find that by building up the fertility of the soil, I can grow a vigorous vine that fights off insects and disease on its own.
"I might lose a little yield, but I compensate that with better tasting fruit."
Moon, the soil fertility consultant, said he has found some early success with an alternative program that utilizes hydrogen peroxide and a brew of beneficial microbes to fight off root-eating nematodes and mildew.
"There is no replacement for methyl bromide in the strict sense," Moon said. "But you can stitch together several different things that can give you a similar effect."
Moon's work has gotten the attention of the California Strawberry Commission and UC Davis, which are conducting field tests on his product.
Opponents of methyl bromide's proposed ban say this innovation is all well and good but that still does not change the attitude in countries such as Japan and Canada, which require that many fruits and vegetables be fumigated before shipping.
"Methyl bromide is the only approved fumigant they will accept," said Richard Matoian, president of the California Grape and Tree Fruit League.
But short of new trade agreements, one Navy bug expert says he has found a solution to that problem, as well: controlling the atmosphere in overseas shipping containers.
"We've found that by lowering the oxygen and raising the carbon dioxide levels, you can put the produce in a state of sleep," said Lt. Cmdr. Robert Gay. "Lettuce doesn't age in the trip over and you won't find an aphid or thrips on it."