Whips are not required to be lighted.
Whip must be 8' above the ground surface, flag: red or orange, minimum size, 6"x12" within 10" of the top of the whip.
It must be upright when the vehicle is stopped.
Off road vehicles need a whip all over at Dumont, road licensed vehicles need a whip while operating in the dunes.
And of course all vehicles must have headlights/tail lights after sunset.
It doesn't seem to me that the flag color is strictly enforced, but I still use a red flag to avoid potential problems.