Foul lines, catcher’s, batter’s and coach’s boxes, next batter’s circles and 3′ line shall be 2″ to 3″ wide and marked with chalk or other white material. Caustic lime must not be used.
Infield may be skinned.
Baseball diamond layout with home plate and pitcher’s mound details.
(U.S. Department of the Army, Office of the Chief of Engineers)