RTC §6357.1: (a) There are exempted from the taxes imposed by this part, the gross receipts from the sale in this state of, and the storage, use, or other consumption in this state of, diesel fuel used in farming

(a) There are exempted from the taxes imposed by this part, the gross receipts from the sale in this state of, and the storage, use, or other consumption in this state of, diesel fuel used in farming activities and food processing. This section shall be implemented as soon as possible, but in no case later than September 1, 2001. (b) For purposes of this section, “farming activities” has the same meaning as “farming business” as set forth in Section 263A of the Internal Revenue Code. “Farming activities” also includes the transportation and delivery of farm products to the marketplace. (c) The exemption established by this section does not apply with respect to either of the following: (1) A tax imposed under the Bradley-Burns Uniform Local Sales and Use Tax Law (Part 1.5 (commencing with Section 7200)) or in accordance with the Transactions and Use Tax Law (Part 1.6 (commencing with Section 7251)). (2) A tax imposed under Section 6051.2 or 6201.2, or under Section 35 of Article XIII of the California Constitution.