The Stockton Record reports that 36-year-old Pedro Becerra and 33-year-old Mario Oheda were arrested on suspicion of auto theft, grand theft and conspiracy to commit a crime. Authorities say Becerra is also suspected of stealing two tankers from Modesto.
Investigators believe the two men stole double semi-truck trailers containing more than 140,000 pounds of walnuts from Gold River Orchards in October.
In California's Central Valley, law enforcement agencies are reporting more thefts of nut crops, which have increased in value amid growing demand.
Growers and nut processors formed a taskforce in October to seek the advice of law enforcement and take steps to protect their products.