Robots may replace some farm laborers

LOS ANGELES — With authorities promising tougher border tactics, farmers who rely on immigrant labor are eyeing an emerging generation of fruit-picking robots and high-tech tractors designed to do everything from pluck premium wine grapes to clean and core lettuce.

Such machines, now in various stages of development, could become essential for harvesting delicate fruits and vegetables that are still picked by hand.

"If we want to maintain our current agriculture here in California, that's where mechanization comes in," said Jack King, national affairs manager for the California Farm Bureau.

California harvests about half the nation's fruits, nuts and vegetables — a huge job that requires about 225,000 workers year-round and double that during the peak summer season.

More than half are immigrants who cross the Mexican border illegally and travel from farm to farm.

Last year, amid heightened immigration enforcement, the seasonal migration was marked by spot worker shortages, and some fruit was left to rot in the fields.

"There's a lot of very nervous people out there in agriculture in terms of what's going to be available in the labor force," said Robert Wample, viticulture and enology program director at California State University, Fresno.

Mechanized picking wouldn't be new for some California crops such as canning tomatoes, low-grade wine grapes and nuts.

But the fresh produce that dominates the state's agricultural output — and that consumers expect to find unblemished in supermarkets — is too fragile to be picked by the machines now in use.

The new pickers rely on advances in computing power and hydraulics that can make robotic limbs and fingers operate with near-human sensitivity.

"The technology is maturing just at the right time to allow us to do this kind of work economically," said Derek Morikawa, whose San Diego-based Vision Robotics has been working with the California Citrus Research Board to develop a fruit picker.

The process involves sending a mechanized scanning unit into orchards and orange groves. Equipped with digital-imaging technology, it creates a three-dimensional map displaying the location, ripeness and quality of fruit.

A robotic picker then follows the maps, using its long mechanical arms to carefully pluck the ripe produce.