WEST SACRAMENTO (CBS13) — Unwanted pests hitching a ride in the mail are a threat to California’s billion-dollar agriculture, but they’re no match for Dozer the Detector Dog.

Dozer and his trainer Jennifer Berger track packages that come through Northern California’s largest postal facility in West Sacramento.

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“They are initially trained on five odors, which is apple, citrus, mango, guava and stone fruit—all hosts for different insects coming into California,” she said.

Over the last year, dog teams at the facility found more than 170 infested parcels of mail. That’s more than all California post offices combined.

“Between diseases and insects, there are literally hundreds of things that are on the states list as being serious potential pests,” said Yolo County Deputy Ag Commissioner Bill Lyon.

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Insects like fruit flies found in some guavas from Florida could devastate California crops.

“If they become too widespread it becomes very expensive and very difficult to eradicate them,” he said.

But since using detector dog teams, Yolo County has intercepted up to 25 packages a day. the program is so successful, the USDA is giving it another $50,000 to add more dogs like Dozer.

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“It’s a true needle in a haystack, and dozer is the needle finder,” he said. “I tried it without him for a couple years and it was hopeless, truly hopeless.”