2005 California Vehicle Code Sections 36300-36305 CHAPTER 3. DRIVERS\' LICENSES

36300.  Any person, while driving or operating an implement of
husbandry incidentally operated or moved over a highway is not
required to obtain a driver's license; except that the driver of any
farm tractor while being used to draw a farm trailer carrying farm
produce between farms or from a farm to a processing or handling
point and return, and the driver of an automatic bale wagon which is
being operated as specified in Section 36102, but is not being
operated as provided in subdivision (k) of Section 36005, shall be in
possession of a driver's license of the appropriate class other than
a junior permit.
36305.  The driver of any implement of husbandry shall possess a
valid class C driver's license when operating a combination of
vehicles at a speed in excess of 25 miles per hour or towing any
implement of husbandry as specified in subdivision (d), (e), or (j)
of Section 36005.