COOPERSTOWN, N.Y. — Michael Rowland knows what he'll be seeing as a new farm season begins: Bag-toting orchard workers with sore backs.

Rowland, an occupational medicine specialist with the Maine Migrant Health Program, has watched as pickers lift a 42-pound bag of fruit and then place that tipsy weight on a 16-foot ladder.

"We give them pain medication and hope they get through the season," he said.

Now some researchers like Rowland are chasing a better option. In efforts that reach from California's central valleys to New York's apple orchards, they're applying a practice better known to office dwellers: Ergonomics.

Why not farm work? It's repetitive and physical. When pay is by the piece, the temptation increases to work faster and under larger loads. And harvest work is usually compressed into a few weeks or months, as maturing fruit in a multi-billion-dollar industry waits for no one. Muscles pay the price.

This year's debate over tougher immigration law brings a new urgency. Concerns about a possible farmworker shortage means more pressure to keep existing workers healthy.

"I can't express how valuable each worker is now," says Al Mulbury, an apple farmer in Plattsburgh, N.Y. "If you mistreat them, they'll go someplace else."

His farm has tested a new fruit bag designed to reduce back and shoulder injuries. This season, wider testing is planned in other states.

In Washington state, the country's largest apple producer, the Pacific Northwest Agricultural and Safety Health Center is testing high-tech orchard ladders that sound an alarm when they risk becoming unbalanced.

And an orchard safety project is planned this season in California and southern Oregon by the Agricultural Ergonomics Research Center at the University of California at Davis. A 2003 study of California migrant workers found strains and sprains showed up three times as much as other injuries, or 31 percent overall.

The cost of such injuries is hard to measure. Paul Leigh with the Center for Health Services Research at the University of California at Davis estimates that sprains and strains cost the agriculture industry $1.266 billion in 2005, about $139 million of that from orchard work.

"Manual labor is probably here to stay," says Giulia Earle-Richardson, a researcher with the Northeast Center for Agricultural and Occupational Health in Cooperstown. "If we can make it less uncomfortable, we should do it."

A study by her office in 2003 shows neck and shoulder sprains are the top problems reported at migrant worker health centers in the Northeast, at 37 percent.

In New York, the country's second-largest apple producer, workers typically use bags weighing up to 42 pounds, or about a bushel, when full, with the weight swinging from just a shoulder strap or two. Earle-Richardson's redesigned bag helps anchor the weight near workers' waists.

Rowland hopes to test some of the bags in Maine this season. They might also work for citrus picking in places such as Florida, where bag loads can reach close to 80 pounds.

In any ergonomics project, the challenge is finding solutions cheap enough to interest farmers, and non-threatening enough to tell workers the tools aren't taking their jobs.

It doesn't always work. One notable flop was a cart for low-lying crops that had workers lying and picking on their stomachs, as if they were swimming over the plants.

It erased the iconic image of farmworkers bending in the fields. But it was quickly rejected. Not a proper position for females, workers said.

Victor Duraj with the University of California at Davis chuckles at the memory. "I think we've already taken it apart for parts," he says.