Vehicle Code § 36615
CHAPTER 6. Size, Weight and Load of Implements of Husbandry
The limitations as to length of vehicles contained in Chapter 4 (commencing with Section 35400) do not apply to implements of husbandry operated or moved over a highway incidental to agricultural operations. Notwithstanding Section 36626, when an implement of husbandry is operated in a combination of vehicles that exceeds the length requirements of Section 35401, the combination is limited to two vehicles in tandem.