LOS ANGELES (AP) Edgar Terry says the biggest threat to his hundreds of acres of strawberries isn't bugs or bad weather.

Instead, he says, it's a new regulation aimed at reducing pollution from the pesticides he uses to boost production and quality on his Ventura County farm.

Beginning this spring, Terry and other growers must cut smog-causing fumigant use by as much as half to help the Southern California county that produces a quarter of the nation's strawberries comply with the federal Clean Air Act.

Growers have few options for replacement crops. Only strawberries, one of the state's most lucrative crops, make economic sense in the coastal area where land prices are relatively high.

"If you do have to let ground go fallow, there's no other crops to grow here," Terry said. "It could be the death blow in some respects."

Last year, Ventura County farmers harvested nearly 12,000 acres of strawberries valued at more than $323 million.

As many as 7,500 acres could be stripped of production as a result of the pesticide cuts, according to figures cited by the California Environmental Protection Agency.

The decreased supply could push strawberry prices higher at grocery stores, said Steve Blank, an agricultural economist at the University of California, Davis.

The growers are facing some of the toughest pesticide restrictions ever imposed in California, said Glenn Brank, a spokesman for the state Department of Pesticide Regulation.

In the past, they have been forced to suspend use of some fumigants but could substitute with others.

In Ventura County, however, growers must limit use of all major farm fumigants during the ozone-heavy months of May through October, when growers prepare soil for strawberries that hit the market in late winter and early spring.

"Neither the federal government nor any other state has ever attempted to do anything like this before," Brank said.

The regulations stem from a 1994 state agreement with the federal Environmental Protection Agency to adhere to the Clean Air Act, which called for the reduction of pesticides containing volatile organic compounds such as methyl bromide, among other measures.

Public health and environmental groups later claimed the state was not abiding by the rules. They filed a lawsuit and won, leading the state to act on the measures.

Other major strawberry-growing areas, such as the Salinas Valley in central California, have not been ordered to cut fumigation because their pollution targets have been met.

Ventura County growers are being hit particularly hard because the agreement with the federal EPA requires pollution cuts from 1991 levels, when strawberry production in the county was only about a third of what it was last year.

"We don't feel like that's right," said Hector Gutierrez, who farms about 120 acres. "If we continue to be able to farm and continue to seek new alternatives, as time goes on we're only going to get better at reducing emissions."

The rules also apply to other fumigated crops such as bell peppers and tomatoes, but those crops account for only about 2,000 acres in the county.

Grower groups are appealing the lawsuit that forced the state Department of Pesticide Regulation to order the cuts. They also sued the department, claiming it neglected to adequately consider alternatives.

In addition, the California EPA has asked its federal counterpart to let the county phase in the caps over four years to allow time for the development of lower-emission methods.

Still, growers are required to comply with the rules in the meantime. They have until Friday to file requests for pesticide permits and will find out by early April exactly how much fumigant they will be allowed to use.

Farmers say the forced reductions could actually increase pollution, since fallowed fields would invite development.

Local ordinances prohibit the development of farmland in much of Ventura County, but as much as a third of the fumigated fields are in urban spots where building could be permitted, according to the state EPA.

"There's a typical saying: First you grow vegetables, then you grow strawberries, then you grow houses," grower Bill Reiman said.

Copyright 2008 The Associated Press.