Cal. Food & Agric. Code § 6341

If anything brought into any county or locality of the state from another county or locality within the state, or from any other state or foreign country, is found to be infested with the seed or propagule of any pest that is not of common occurrence in the county or locality into which the shipment is brought, the director or the commissioner shall notify the owner or bailee of such shipment to return it to the point from which the shipment was made.