Some Oregon farmers contend that the U.S. government's decision to place National Guard troops along the Mexican border is contributing to a shortage of workers to pick ripe fruit.

Terry Drazdoff said farmworkers should be harvesting 25 tons of fruit per day from his Polk County cherry orchard. Instead, the farmer can only hire enough migrant farmworkers to pick 6 tons.

"Why did President Bush do this before harvest?" Drazdoff said.

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Though Drazdoff and several other growers blamed the government's attempt to limit the flow of illegal immigrants, experts in migrant labor say the number of migrant workers passing through the Willamette Valley has been dropping for years.

Daniel Quinones, a farmworker representative for the Oregon Employment Department, said there is simply less work for them as more farmers switch to machine-harvested crops, such as grass seed.

And Quinones said the tight supply of pickers has been further stretched thin because a late strawberry harvest overlapped with the start of the sweet cherry harvest, and picking has started at some raspberry and blueberry farms.

Quinones, however, said that the controversy over illegal immigration might be discouraging some workers from following the crop harvests on the West Coast.

"There is a lot of fear out there because of what's happening around the nation with the immigration situation," he said.

Reliable estimates about the size of a work force that might spend only a few days or weeks in Oregon are not available, although there is little doubt that it has declined throughout the years, state employment officials said.

Some blame this year's shortage on last year's harvest. An unusual weather pattern resulted in one of the worst years ever for cherry growers. As a result, cherry pickers might be skipping the Willamette Valley this year and going directly to The Dalles and the Hood River area, where a good crop is viewed as a sure thing.

Though cherry growers can use machines to harvest their crop, the hand-picked fruit is more desirable. More stems are left on hand-picked fruit, adding to the presentation of maraschino cherries dropped in cocktails and placed atop ice cream sundaes.

Experienced cherry pickers, who are paid by the bucket, often earn $11 or $12 per hour, said Don Nusom, who grows cherries near Gervais.

Those new to cherry picking and less skilled, such as a couple of workers Nusom recently hired, make minimum wage.

Nusom said the pickers he hires all have documents showing their legal status, but he wouldn't be surprised if some of them entered the country illegally.

"Our entire labor supply is pretty much immigration, whether they're legal or illegal," he said.