Ten miles outside of Modesto, in the farming town of Hughson off Highway 99, the Duarte Nursery is at the front line of dramatic changes under way in California's immense agriculture industry.
The family-run nursery, founded in 1976, is one of the largest in the United States, and there's a good chance the berries, nuts and citrus fruits eaten across the West began their journey to market as seedlings in Duarte's 30 acres of greenhouses, labs and breeding stations.
The nursery's owners have built a thriving business using state-of-the-art techniques to develop varieties adapted to the particular conditions and pests that California farmers face.
These days, according to John Duarte, president of the nursery, that means breeding for elevated levels of heat and salt, which researchers say are symptoms of climate change, even if Duarte doesn't necessarily see it that way.
"Whether it's carbon built up in the atmosphere or just friggin' bad luck," he said, "the conditions are straining us."
The cause of Duarte's woes might be in dispute among farmers in California's $31 billion agriculture industry, but the symptoms are clear. From the vast fields of fruits and nuts in the Central Valley to the wineries of Napa and Sonoma, increasingly volatile weather is altering the fundamental conditions for growing food, California's largest industry.
Farmers are in many ways at the front line of climate change. They conjure food from soil, sunlight and water, which are profoundly affected, scientists say, by climate change. Stresses have emerged across the state as water supplies tighten. Rain is coming at unexpected times. Winters aren't getting cold enough. And salt from the rising ocean is making its way into Central Valley water.
Climate change already has cost farmers money. In the Central Valley, some growers are paying more for seeds designed to withstand the new extremes.
At the nurseries and colleges in what Duarte calls "the Silicon Valley of agricultural innovation," these changing conditions have forced botanists to look for varieties of almond, pepper, citrus, cherry and other crops resistant to drought and salt.
Other interests also are bracing for dramatic change. The crop insurance industry is calculating potential billion-dollar losses from extreme weather conditions, as well as floods and fires that occur in their wake. Climate change could join the ranks of earthquake and hurricane insurance as a special -- and expensive -- problem for insurers.
Over 20 years, there has been more than $500 million in crop losses from heat waves, floods and ill-timed rainstorms in the agricultural counties of San Joaquin, Merced, Kings, Kern, Napa and Sonoma, according to a study last year by Stanford University researchers.
"Compared to 20 or 30 years ago, farmers are recognizing a lot more risk factors in climate events," said Jeff Yasui, director of the U.S. Department of Agriculture's Risk Management Agency office in California, which handles crop insurance in the state.
Climate and agriculture scientists predicted much of this. Charles Kolstad, an environmental economist at the University of California at Santa Barbara, said California agriculture is being hit by converging forces prompted by climate change: longer seasons of extreme heat, shorter cold seasons and dwindling water supplies.
Climate scientists believe Earth's average temperature will rise at least 2 degrees in the next four dec-ades, their most conservative estimate. Along the way, the yields of citrus crops in the San Joaquin Valley are expected to drop about 18 percent, grapes about 6 percent, and cherries and other orchard crops about 9 percent.