ENVIRONMENT : Blazing Farms Are Under Fire in Northwest : Burning off grass-seed fields is said to hike yields. Smoke also causes illness, traffic deaths.

People in north Idaho, east Washington and east Oregon are enduring the annual pall of smoke that hangs like a grimy cloak when grass-seed farmers burn their fields from late August to October.

The smoke is blamed for triggering allergies, causing headaches and sore throats and forcing those with respiratory ailments to stay indoors or, in worse cases, to seek medical attention.

On a day last year that has been dubbed “Black Wednesday,” telephone complaints about the smoke flooded an Idaho state health agency to the point that a new phone line and a new employee have been added this year.

Smoke has forced motorists on U.S. 95 and other highways to switch on their headlights in midafternoon. Last year, it grounded a seaplane service on Lake Coeur d’Alene, a tourist center, and forced a United Way barbecue indoors.

And it was blinding smoke that was blamed for a 24-car pileup along Interstate 5 near Albany, Ore., in August, 1988. The accident killed seven and injured 38.

Grass-seed farmers, who also grow wheat, barley and other crops, burn their fields annually to kill weeds and insects and to promote growth.

Oregon’s 400,000 acres in bluegrass, fescue, rye and other varieties make it the nation’s top grass-seed producer, but the mass traffic accident spurred a public outcry against burning of grass fields. As a result, measures were signed into law on Aug. 7 that will reduce the yearly burning in the Willamette Valley to a maximum of 40,000 acres by 1998.

The legislation’s sponsor, state Sen. Grattan Kerans of Eugene, refers to the crash as the day “when the public mind changed” and adds: “We were using our lungs for their garbage disposal.”

North Idaho and east Washington, the nation’s No. 2 grass-seed producer, are also facing voter rebellions against the decades-long practice of burning fields.

Many of the 400 members of the Intermountain Grass Growers Assn. are resigned to the inevitability of an eventual ban on burning.

“Our backs are against the wall,” said Elmer Satchwell before putting a propane torch to some of his 1,100 acres of bluegrass outside Rathdrum on Aug. 15.

Grass farmers had already voluntarily agreed to limit this year’s burning to 14 days during the 45-day burn season, to refrain from burning on Fridays, weekends and Labor Day and to support research for alternatives to burning.

Nevertheless, the complaints are pouring in this year, too.

“It’s got to stop,” said Dorothy Long, 59, a retired teacher in Hope, Ida., whose husband, Art, is president of the Sandpoint (Ida.) Clean Air Coalition. “I taught in my geography classes that fire-farming is a primitive agricultural pursuit. I just can’t believe it still goes on here.”

It goes on because farmers are certain that fire spawns more seeds for the next year. Wayne Meyer, growers’ group president, said that 564 pounds of seed are produced on a burned acre; without burning, the yield is only 96 pounds.

Meyer, Satchwell and others say that, if they cannot burn, they will have to use more chemicals to control weeds and bugs. Critics are unmoved.

“The chemical talk is part of a series of scare tactics,” said Robert Duffield, who moved his computer design company from San Diego, Calif., to Coeur d’Alene a few years ago and is a clean-air activist. “The truth is, they already put a ton of chemicals on.”

Clean-air groups got nowhere with the Idaho Legislature earlier this year. In Washington, action was taken in Spokane, which trailed only Los Angeles as the worst violator of federal carbon monoxide standards in 1988-89. Spokane County officials last year imposed some restrictions on burning.

Oregon growers’ spokesman Dave Nelson says farmers there expect to “make the transition” away from burning by 1998 because of a “dramatic increase” in seed output as a result of genetic research. Washington and Idaho growers, though, say laboratories are a long way from reproducing seeds the way fire does.

In an attempt to reduce smoke last year, growers agreed to burn on fewer days, but the plan backfired when heavier burning on selected days spurred the loudest uproar in memory.

This year, the growers’ group is spending $35,000 on two computer-equipped weather stations and has hired a meteorologist to determine the most favorable conditions for burning. Some, like Satchwell, hire security guards to restrain traffic when the smoke drifts over highways.

But critic Duffield says of the precautions, “It’s done only to create good PR.”