YELLOW is symbolizes daisies and the sun, both of which come from nature -- with which most people identify a hippy.
NOTE: the title of this page -- The HIPpy Tribe -- appears in the tribal color.
For those of you into graphics, the tribal color is
255, 255, 0 (or FFFF00) in RGB, or
0, 0, 255, 0 (or 0000FF00) in CMYK.