Rumbling through an olive orchard, a machine harvester towers over a row of trees, stripping the small green fruit and shooting them into a rapidly filling container.

This may be the future of farming in an era of worsening labor scarcity.

In the last 10 years, new olive growers and olive oil producers have been planting olives in super high-density grids and switching from hand labor to mechanized labor.

An olive harvester can take the olives from a whole acre of trees in an hour, and it takes far fewer people to do the job. The containers are tipped into a waiting truck, and the olives are taken to a nearby mill and pressed into olive oil. Harvesting goes on through the day and night in much of November.

The dwindling supply of workers has long been on the horizon, but there's a new urgency for farmers to shift to machines to harvest crops around the region and state.

Farmers had significant trouble finding people to tend and pick their crops this year, said Bryan Little, director of labor affairs for California Farm Bureau.

"Most folks were reporting to us that they were between 20 and 30 percent short on labor," Little said.

Some cherry growers were able to pick only once this year, said UC Cooperative Extension farm adviser Chuck Ingels. That's a problem because, ideally, they'd pick as fruit colors and ripens.

"They're finding that if they can't get labor to pick their crops, they're just not able to farm anymore," Ingels said. "So what they're going to is mechanization."

In the Amador wine country, grape grower Dick Martella is relieved that this year's harvest went relatively smoothly despite difficulty finding workers. In the spring, Martella said, labor contractors were holding meetings warning growers that only about 60 percent of their usual labor force were available.

Many vineyards didn't get adequately suckered – the process of pruning vines to ensure sun exposure and the flow of air through the canopy of grapes – early enough because of the shortage. Under pressure to find workers, growers raised their pay rates by about a dollar an hour, to $13.

Grape growers were lucky. As it turned out, the weather enabled a long, orderly harvest season that started at the end of August and had some growers picking into November. If rain or other conditions had forced grape growers to pick all at once, Martella said, it would have been a crisis.

"If you can't mechanize, you will be out of business sooner or later," said Martella, who grows zinfandel, sauvignon blanc and other varietals.

In the Sacramento River Delta, growers scrambled to find crews to pick pears and apples. Sometimes pickers would leave at midharvest if they heard a different grower was paying more.

The only reason local pear farmers didn't end up having to leave fruit on the trees, said Doug Hemly, who grows and packs pears and apples in Courtland, was that the crop was smaller than estimated. But even with a smaller crop of pears – the third-biggest farm commodity in Sacramento County – it was tough to find pickers.

"I haven't talked to anybody that didn't have a certain level of difficulty," Hemly said. "It appears to be the new normal."

'Shortage' questioned

Rising wages in Mexico, the state of the U.S. economy, and a demographic shift among the ranks of foreign workers who American farmers rely upon factor into the labor shortage.

An analysis of data from rural Mexico shows that "the same departure from farm work that characterized U.S. farm labor history is well under way in Mexico," wrote UC Davis agricultural economist J. Edward Taylor in a soon-to-be published paper in an economic journal, Applied Economic Perspectives and Policy. The paper suggests that U.S. farmers switch to labor-saving technologies and move away from labor-intensive crops.

Not everyone out in the fields and orchards agrees that there's a shortage of agricultural workers, however.

Sebastian Bariani, of family-owned Bariani Olive Oil, said he's seen a steady stream of people dropping by and asking for work this fall. One man came looking for work for a crew of 40 after they finished harvesting grapes. "They will do any kind of job – not just picking olives," he said. "From my perspective, I don't think there are any labor shortages. I'd be surprised if there are."

Bariani said he had to turn the people away, because his family does all of the work on their own and by hand on acreage in rural Yolo County.

From the perspective of farmworkers, it also doesn't appear that there's a labor shortage, said Maria Machuca, spokeswoman for the United Farm Workers of America. "Simple economics tells us that if there was in fact a labor shortage, we would be seeing an increase in wages and better benefits for workers," she said in an email. "We are not seeing that yet in nonunion companies."

Pear growers paid workers about 20 percent more this year, Hemly said, but he added that raising wages doesn't solve the problem.

"It doesn't matter what you pay if there's nobody to pay it to," he said. "If there are 100 people needed someplace, and there's only 60, no matter what you pay, you will not get 40 more people. The concept that raising prices will dramatically increase the labor supply is a fallacy."

In the table olive harvest, Pat Campbell, vice president of operations for Corning-based Lindsay Olives, said olive growers had a hard time finding workers. The quality of the crop suffers when growers can't get olives off the trees when they need to, he said.

High-tech harvest

The table olive industry has high hopes for new machine harvesting technology.

UC Davis agriculture experts, farmers and industry leaders gathered last month in Orland to watch a demonstration of the first mechanical harvest of Manzanilla table olives in California. The new technology could revive the industry, which has been battered by a lack of labor for hand harvesting.

California growers of apples and pears see similar hope in emerging technology for harvesting their crops.

Picking pears, for example, is a grueling job that requires someone strong enough to quickly hoist 50-pound bags of pears up and down tall aluminum ladders in sometimes punishing heat, all without bruising the fruit. New technology would cut down on the need for ladders and enable workers with less skill or strength to pick the fruit. For apples and pears, there are platforms for workers to stand on that move through the orchard while the workers feed the fruit into flexible tubes, where suction carries the fruit to bins.

"It's definitely on the radar for growers in the industry," Ingels said.

But it'll take time and money to make the switch. The mechanized systems available now for pears, for example, require a narrower hedgerow – different from the layout of the orchards of Bartlett pear trees area growers tend. Harvesters are expensive, too.

Given that cost, some growers said it's difficult to see how mechanization will happen for smaller farms such as those in the Amador wine country. The region is noted for its family-operated vineyards.

"That's going to be tough for us," Martella said.

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