Given all these careful specifications, it is a little surprising that there is one not-so-small aspect of playing field design that isn’t specified: namely, the material of which the “grass” is to be made.
Natural grass sufficed nicely for more than a century. Then, after the grass planted in the Astrodome for its grand opening in 1965 died, artificial nylon baseball turf made its debut. (The deceased natural grass was Tifway 419 Bermuda, for any horticulturalists out there.) The result was baseball on so-called “carpet”. (More trivia? The first game played on Astroturf was played on April 8, 1966. And, yes, it is possible for rain to postpone even an indoor game: on June 15, 1976, an Astros game was rained out because of flooding–on the streets of Houston.)
Grass vs. carpet is a debate that rages among sports fans, players, and management alike. Does it cause injury? Probably, given that there is concrete beneath the carpet’s underpadding, though artificial turf-related injuries seem less prevalent in baseball than in the National Football League. One study conducted after the Cincinnati Reds’ arrival in carpeted Riverfront Stadium in 1970 reported an increase in abrasion and burn injuries, particularly to the palms and knees, but no notable change in the frequency of other injuries. No one believed it then–especially the guys with all kinds of leg problems caused, at least in part, by patrolling rock-hard outfields and sliding on the unforgiving surface. In the decades since, the superiority of grass has virtually been conceded. Consider the fact that of the new parks opened between 1990 and 1998, eight have grass surfaces, and only one has carpet.
Artificial turf has had an undeniable effect on the speed of the game. The ball gets through the infield faster, which has led the interior defense’s to play deeper. If it gets through, an extra-base hit seems more likely on turf than on grass. As Tom Seaver said a few years ago, “Even hitters like Mike Schmidt of Philadelphia have begun to put turf to work, swinging for the gaps when they get a pitch that’s unsuited to pulling for a possible home run. The current style of compact, golf-style swinging, taught by Charlie Lau and epitomized by George Brett of the Royals, is perfectly suited to artificial turf.”