By Cambi Brown

STOCKTON (CBS13) — Thieves are targeting walnut farmers whose crops have seen a significant increase in value in recent years.

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The price of walnuts have more than tripled in recent years, going from 60 cents to $2 a pound.

In the back of a truck, Skipp Foppiano says he has almost $100,000 worth of walnuts.

“The theft is getting bad. You’ll see more fences going up around fields,” he said. “Its gotten worse lately because the price of the walnuts is so much higher now.”

Thieves are finding inventive ways to steal the crop. Foppiano says if he leaves the truck out, he’ll be left with a just semi in the morning.

“They’ll come with a truck and unhook it and steal it all,” he said.

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Foppiano has 24-hour security, puts all of his equipment away at night and even locks the bins filled with walnuts.

But because of the possibility of a big payout, the criminals are taking greater risks.

“There’s trucks that come in with phony paperwork. They’ll hook up to a trailer, sign out and then take off,” he said.

It’s a huge loss, and if it keeps happening, consumers could pay more at the grocery store. That’s why Foppiano doesn’t mind paying to protect his orchard.

“Thousands of dollars, but its cheaper than losing it,” he said.

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Farmers in the area get together and share the ways they’ve been conned by thieves, so they can be on the lookout and protect their investment.