Have you noticed the high price of walnuts and other nuts lately? You're not alone. California walnuts and almonds have seen prices soar by 10 to 15 percent in the past year as worldwide demand, especially from China, has increased, according to a recent report from Food Business News. The price increases have led to higher profits for nut growers, but they have also led to a surprising offshoot: an increase in nut-related crime.

The trend started a few years ago. Back in 2012, two truckloads of walnuts valued at $300,000 were stolen in Northern California. That was just the beginning. In November some thieves took off with 140,000 pounds of walnuts valued at $400,000, a crime that was called "brazen" in a report from the Los Angeles Times. Two men were arrested for that crime a few days ago and have been charged with auto theft and grand theft.

Those big thefts are just the tip of the nut pile. The Associated Press recently looked into this string of nut thefts and came up with a long list of crimes, including hundreds of thousands of dollars' worth of almonds and pistachios. The stolen nuts are reportedly destined for the black market or for sale in some of Los Angeles' farmers markets.

All of this comes in response to a tripling of walnut prices over the past five years, which has inspired seemingly everybody in California to plant nut crops. "Right now, everybody wants to be a nut grower because it's kind of like the gold rush of the 1850s," almond farmer Kevin Fondse told the AP. "Everybody wants the gold."

Nut farmers aren't taking the threat lying down. They have organized and gone high-tech, installing more lights and adding cameras to monitor their crops. The AP reports that growers and processors are now fingerprinting their drivers, checking paperwork (since some of it has been fake or missing in the past) and keeping driver photos on file.

Although all of the thefts are adding up, no one has a tally of how much they have cost California growers to date, since no single agency tracks and reports these numbers. Police suspect that organized crime is involved, although no specific organizations have been linked to the nut rustling.

Meanwhile, supplies remain tight. The USDA recently reported that almond exports to China and Europe are expected to grow 6 percent this year, but at the same time production for 2013-2014 is expected to be about 2 percent lower than last year. Weather, including the current drought, is the biggest factor contributing to decreased production.

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