(NapaValleyRegister) - Californians can order license plates paying tribute to firefighters, Olympic athletes, Lake Tahoe and even the post-9/11 war on terror. In the coming weeks, one more cause will be added to that list: farming. The state Department of Motor Vehicles will begin issuing the Cal Ag Special License Plate in March or April, spokesman Artemio Armenta confirmed Tuesday. Production of automotive plates is under way, with motorcycle tags to follow, he said