Do all of the lines on a field need to be of uniform color?
While common sense would prevail that they should be of the same color that is always not the case due to fields being utilized by more than one sport. In this case it was a grass field, not an artificial surface. It was a U9 “travel” game.
The touch lines were of different colors, the goal lines were different than the touch lines and the penalty area was yet another color. I know there is a law regarding the size of the lines but I could find nothing requiring the uniformity of color for all boundaries. “..all lines must be of the same width, which must not be more than 12cm (5inches)…” the game was played but our coach told me that his team and the referee had difficulty throughout the game identifying if a ball was in or out of a particular are of the field.
USSF answer (May 4, 2010):
While Law 1 states only that the goal posts and crossbar must be colored white, it is traditional that all field markings are in white. And traditional means that this is the way it is supposed to be done. Field managers should not be artistic geniuses; they should prepare the field in accordance with the expected: White lines.
We understand that some competitions use multipurpose fields and that the participants must cope with that.