Major League ballpark weathers challenges to become one of baseball’s finest new facilities
By Mike Jiggens
Constructing the playing surface at the New York Mets’ new baseball
stadium in Flushing Meadows-Queens featured the usual challenges with
weather and differences of opinion, but the end result was a
state-of-the-art facility that is one of Major League Baseball’s finest.
Bill Deacon, director of field operations for Citi Field, which opened at the start of the 2009 baseball season, spoke about his role in the ballpark’s field construction at an educational seminar sponsored by Plant Products at Oaville, Ont.’s Deerfield Golf Club in November.
Deacon joined the Mets’ organization during the club’s final few seasons at Shea Stadium before the site of its parking lot was transformed into Citi Field. The Canadian-born head groundskeeper, who was educated at both Penn State University and the Niagara Parks School of Horticulture, had been assistant groundskeeper for the San Diego Padres before coming to the Mets in 2006.
Both Shea Stadium and Citi Field were built on former swampland. Shea was built in the 1960s, about three feet above the water table whereas the $850-million Citi Field sits closer to 11 feet above the water table. The playing field actually “floats.”
Its drainage system was specially designed to move with the field and features a high-density polyethylene pipe which is able to maintain its flexibility.
A lightweight, porous concrete was poured in late 2006 at the site. The concrete is meant to prevent settling on marshlands and wet, boggy areas. An eight-foot surcharge was put atop the concrete to eliminate settling. When it was removed, there was six inches less settling in left field than in right field, and not much more has been seen since, Deacon said.
Soil engineers had predicted the worst settling would be experienced in the first three to five years.
“We’ve seen a little, but not a lot.”
Citi Field’s infield was originally designed with a one per cent slope, but Deacon said he preferred something lesser—about .33 per cent. A compromise was reached with the architect to realize a .45 per cent slope that would maximize playability and provide adequate drainage from the infield turf.
Deacon and the field’s architect also disagreed with how the warning track should be sloped, but the designer’s strategy won out in this instance. Deacon wanted the track to slope toward the outside wall while the architect preferred sloping the track toward the outfield turf to allow the field drainage to drain the track.
When it rains, Deacon said the minor particle size of the warning track material gets washed about three feet into the turf, resulting in the outer edges having to be frequently sodded.
If it was a native soil field, it wouldn’t be much of an issue, he said, because the warning track’s fine material wouldn’t clog it up. But, because it’s a sand-based field, and the particle size is similar to that of the warning track material, it’s important to have as much pore space as possible, he said. Having the warning track slope toward the field tends to clog it up.
A crushed lava material was chosen for the warning track mix because of its colour. The team’s ownership likes the red-purple colour’s contrast with the outfield grass. Four inches of the material sits atop three-eighths of an inch of stone.
While there is minimal maintenance required for the warning track, watering is necessary and it is dragged out a little.
Deacon said delivery of the warning track material was probably the greatest ordeal in the field’s construction process. It had been shipped from out of state by railcar, but there was no place close to the stadium to offload it. The material eventually made its way to the field aboard teamster trucks which contributed to a “huge” expense.
Citi Field’s playing surface was built with a tested 90-10 mix of sand to peat and constructed similar to a USGA-specification green. There is no choker layer and a three-eighths-inch gravel layer sits beneath the sand. Its drainage capacity is well within ideal paramaters, Deacon said.
Choosing the right infield mix was a lengthy process. When the Mets played at Shea Stadium, one of their biggest complaints was that the infield mix often “chunked out” during play. If a ball hit one of those chunks, a “bad hop” would frequently result, putting the fielder at a disadvantage.
Deacon said he called the manufacturer of the mix to see what solutions might be reached. The mix had been 87 per cent sand, which Deacon said was abnormally high for a Major League Baseball infield mix. It had almost no silt and a fair amount of clay. Deacon said he wanted a silt and clay ratio of between 0.5 and one, and the manufacturer told him he’d have to work the infield mix up.
“I knew from past experience I didn’t need to work the infield mix up. I just needed to amend it.”
Deacon said he found someone who agreed with his ideal of a workable mix, and, when the team moved to Citi Field, an infield mix fitting his preferred specifications was blended.
“It’s an engineered mix which means he mined the clay and ran it through a computerized pug mill and came up with an infield mix that sets you where you want it.”
Deacon’s new supplier sells standard 60-20-20 infield mixes, but that customized for Citi Field is 53 per cent sand, 20 per cent silt and 26 per cent clay. The medium coarse sand provides stability, and the percentage of clay is high enough to hold together and negate “chunking out.”
The pitcher’s mound is built out of infield mix because of its cheaper cost. The pitcher’s rubber is taken and a 30-degree pattern toward where the pitcher is going to land is cut out. The mound clay comes from the same manufacturer which provides Citi Field’s infield mix.
“It comes out of the bag very easy to work with,” Deacon said.
A black gumbo-type mound clay was used at Shea Stadium. The team switched to the new clay once moving to Citi Field because the material simply shades off when pitchers are landing. He said other mound mixes with high clay content hold together well, but, when it pops out, big chunks are unearthed and end up in the infield grass.
Deacon said he builds his mound from the rubber out. He sets the rubber with a transit level and builds everything from there, including the table. For the slope, he takes a piece from a two-by-four, puts a level on it, and, for every foot out the mound is sloped down an inch.
The field’s sod was grown in southern New Jersey where the native soil is 93 per cent sand which matches closely with that at Citi Field. Deacon said there is “beautiful” sod grown closer to the ballpark, but it’s grown on clay. The sod used is a four-way blend of Kentucky bluegrasses (Midnight Star, Apollo, P105 and Moonlight). The first three were grown at the sod farm and interseeded at the stadium with Moonlight, known for its dark colour which helped offset P105’s comparatively lighter shade. The P105, however, is both more aggressive and wear tolerant.
The field growing the sod had been seeded 13 months before it was cut.
“We went with something fairly young as far as cutting sod at 13 months,” Deacon said. “Generally, they like to do 18 months at a sod farm.”
The one potential drawback to the bluegrass blend was that P105 produces significant thatch which, although is fine for football and soccer, causes “snaking” of the ball in baseball.
“We wanted a thatch-free grass when we brought it in.”
The field was sodded in November, making the new grass cover almost 18 months old by the time the first home game was played in the spring.
The area behind home plate is a mostly shaded area, and root growth of the newly-laid sod wasn’t as prosperous as that throughout the rest of the field.
A late fall fertilizer was put down along with a snow mould application. Deacon said the field was also painted with a green dye which acted as a turf protectant. The dye was applied once everything stopped growing. It coated the leaf and was left to sit there, giving the turf an easier time to emerge from dormancy, he said. The chosen bluegrass blend is slow to green up in the spring.
The dye is also used following such heavy-traffic, non-baseball events as concerts. Following a magnet sweep of the field, which picks up screws and other metallic debris, the dye is used on any areas where the turf has yellowed. Deacon said dyed areas tend to come back quick.
Between 61/2 and seven pounds of nitrogen are used, which Deacon said is slightly higher than recommended on bluegrass.
Mowing of the field is usually done at a height of one inch, but it can range between seven-eighths of an inch to 11/4 inches. Cutting at less than an inch can be “a little dicy” during the months of July and August, he said. Mowing at more than an inch, which produced a “beautiful” field, was done to accommodate a slow-fielding first-baseman the Mets had in their lineup, but the height of cut was lowered to one inch once he was gone from the team.
The field is mowed every day during the baseball season.
Citi Field is equipped with a SubAir system which not only keeps the soil temperatures moderated, but has other useful attributes. During periods of excessive rainfall when the field is tarped for prolonged periods of time, the SubAir unit can inflate the tarp so that it hovers six to 10 inches above the ground, allowing for better air movement beneath.
Even though the SubAir system can generate temperatures of 110 degrees Fahrenheit throughout the soil, it is more widely used during the summer months by moving air and sumping water after a rainfall.
The stadium’s drainage mainline, which runs almost down the centre of the field, works hand in hand with the SubAir system. From the main are six-inch laterals positioned every 10 feet.
“It’s complete overkill, but it’s designed this way because the SubAir unit pushes air in and holds it.”
In addition to Deacon’s keynote address, those in attendance were also updated about chinch bug control, understanding nematodes, grass seed and non-selective weed control. –