The following are the ground rules for Wrigley Field.
Fair ball striking railing or screen attached to bleacher wall and rebounding onto playing field: In Play.
Fair ball lodges in screen attached to bleacher wall: Two Bases.
Fair batted ball lodges in vines on bleacher wall: Two Bases.
Fair ball enters vines on bleacher wall and rebounds onto playing field: In Play.
Fair ball lodges in or under grates in left or right field: Two Bases.
Ball lodging on, under or in the bullpen seating area: Out of Play. A ball is deemed to be lodged when it goes in or behind equipment or seating or, in the umpire's judgment, is deemed otherwise unplayable.
Ball enters the bullpen seating area and rebounds out of the seating area: In Play.