Milltown Soccer is part of the Tualatin Hills Junior Soccer League (THJSL).  All clubs under THJSL follow their rules, including the jewelry policy:

Jewelry:

No earrings, "piercings", watches, rings, necklaces, bracelets, wristbands, or hard casts may be worn during game play or practice. Hair bands, if used, must be elastic. Other articles that may be considered by the referee to endanger either the wearer or other players must also be removed. Religious/medical bracelets and necklaces are not considered "jewelry" but must be taped to the body to the satisfaction of the referee.  Failure to obey the referee will automatically disqualify the player from participation until the referee determines the hazard has been resolved.