In 2009, American Family Field's outfield was replaced with "Lo-Mo" Kentucky bluegrass just like the infield was the prior year. The new turf, common in other ballparks around baseball, is denser and has a sand base, instead of the sand and clay mix under the original grass. The turf yields truer hops and fewer instances in which the baseball skips under an outfielder's glove than the previous turf. Also for the 2009 season, the Harley-Davidson Deck was opened on the field level of the stadium in left-center field.