Look, I’m not accusing Nicolas Cage or anybody else involved in the movie “Pig” of lying. But after a search around Oregon, I haven’t been able to find a single person who hunts the state’s wild truffles with a hog, as Mr. Cage did in the film.

Pigs will snarf as many truffles as they can, for one thing. They rip up the forest floor like cloven-hoofed bulldozers, which is why it’s been illegal to bring them on truffle hunts in Italy since the 1980s. And when a harvester is on the way to a secret truffle spot, they tend to give the game away.

“You put a 300-pound pig in the back of your Subaru and people know where you’re going,” said Deb Walker, a professional dog trainer, as she instructed about two dozen humans who had come to a farm outside Eugene this month to learn the art of working with canines to sniff out fussy, perishable, mysterious wild truffles. Around 2,000 dogs in the Pacific Northwest have graduated from similar courses over the past 20 years.

While many people are content simply to teach their dogs an exotic new trick, others have taken up truffle hunting as a serious hobby. A few hunters have turned it into a profitable side hustle during high season, which runs from October to May. Other harvesters, no one knows quite how many, comb the loamy soil under Douglas firs with long-fingered rakes instead of dogs.

Wild-mushroom brokers buy them at trading posts in the woods that can take on the atmosphere of mining camps in a gold rush. Chefs in Portland, Seattle and other cities are visited by people with dirt under their nails offering baskets, buckets and leather satchels loaded with small white truffles and big, knobby black ones at prices that can reach $800 a pound. Oregon truffles have been made into oil, cheese, chocolate, beer and vodka.