Grant Trenbeath, Chase Field's first and only head groundskeeper, has become one of professional sports' leading authorities in growing and maintaining natural grass in a retractable-roof environment. Missing just three games in the D-backs' 15-plus years of existence, the Oregon native and his four-person grounds crew are on site to tend to the Bull's-Eye Bermuda grass -- as well as the entire playing surface -- on a daily basis.
Trenbeath is joined by assistant head groundskeeper and mechanic Karl Gant, who has worked on home plate and the baselines since the team's inception. Outfield landscape manager Doug Pierski is in his 13th season and handles the upkeep of the pitcher's mound, the walk mowing of the field, some irrigation work and the landscaping of the outside lawn areas and vegetation on Chase Field property. Brandon Isbell maintains the bullpen mounds and walk mows the infield, and Chris Arnold maintains the pitcher's mound and the warning track, along with mowing duties.
Trenbeath talked with D-backs.com about some of he and his staff's trade secrets when it comes to maintaining the D-backs' home field.
D-backs.com: Whether the team is home or away, you and your guys are always hard at work. Describe your typical workday.
Grant Trenbeath: During a homestand, it can range from 12-14 hours. Work days aren't as long when the team is away. When the team is on the road, you are still on. I try to come in every single day during the season just to make sure irrigation is running right, because if you do have something go wrong with the irrigation, you can get smoked in a heartbeat without knowing it.
It's nice to have the comfort and security of knowing that everything is all right. It's like a child out there, and you want to keep up to it. I try to speed up and jump on everything and do as much as I can to the field at that time, so when the first day of the road trip hits and we open the roof and the sun hits the field that following morning, we are done beating it up.
The new sod will come in that day and they will re-sod the areas in front of and behind the pitcher's mound and umpire spots at first and third base. Umpires can be more destructive than players on the field.
The day before a homestand is crucial. We get everything mowed in terms of patterns, rework the infield dirt, clean the warning track and repaint all of the lines and boxes.
D-backs.com: For a typical 6:40 p.m. start, how early do you and your crew get to work?
Trenbreath: The crew reports four hours before the first activity on the field. So if a visiting team elects to have an early workout, which would be 1:30 in the afternoon, that would mean start time's at 9:30 in the morning.
A few guys are cleaning up the warning track from debris that fell onto the field from the cleanup crews the night before. Mowing is every other day because of the growing conditions. We nail drag home-plate area two or three times. They are homemade. It's just a two-by-four with nails and rope, and that is what we use on our infield.
We prep the mound, and once the warning track is clean, they come back and nail drag the warning track and paint the outfield warning track with the foul lines. Bases are put out, and then we clean up and sweep the on-deck circles. They hand water some of the edges and dry areas along with replacing divots with some green sand. We prep and clean the bullpen areas. Pregame consists of the same duties as prior to batting practice, in addition to cleaning up after the players with vacuums cleaning up leftover gum and sunflower seeds.
D-backs.com: For as much work as you and your crew put in before every game, I imagine the same goes for after the final out of the night, right?
Trenbreath: Postgame takes an hour and a half to two [hours] to do the cleanup. We repack the clay on the mound and put a tarp over it, along with putting a tarp over the home-plate area. We clean up the warning track and turf in terms of sunflower seeds and bubble gum, and then rake seeds into the infield dirt.
There is more re-dragging of the infield, and I start my irrigation. Sometimes we will put light carts out if necessary, and then go home and start all over the next day.
There is a lot of old school meets new technology considering the tools of the trade. Up until 2010, we mowed the entire outfield with a basic triplex mower. With last year's MLB All-Star Game, we switched gears and mowed the entire field with walk-behind mowers. Push mowers are the old, while laser grating is the new. You have to balance what you know has worked for you in the past, and hypothetically guess where some of the new technology can take you.
Being that we have to re-sod the field every year because of the motocross and monster truck events, having a laser grater here is huge. Before the new sod comes in March, lasers set up lines to Major League specifications. Each field can be different in its own right, but that being said, your bases have to be 90 feet apart, the mound has to be 60 feet, six inches [from home], and the pitching rubber needs to be 10 inches above home plate. We are measured on it, and if you are a quarter inch off, you're off. It's technology that is out there that needs to be taken advantage of, and we do.
D-backs.com: Chase Field was MLB's first retractable roof housing a natural grass surface. Now it seems almost standard in the game.
Trenbreath: There really wasn't a whole lot in terms of referring to somebody and saying, "Hey, you know with this problem, what do you do here?" It's kind of like walking the plank so to speak, and you were the first one to do it.
You look at the Major Leagues now and you've got Seattle, Houston, Milwaukee and now Miami, all with retractable roof and natural grass stadiums. I like to think that our situation here gave everybody hope that it could be done and everybody has followed suit. Besides Miami being its first year for their field, those other places are on their second and third head groundskeeper, whereas I have been here from Day 1 and been the only groundskeeper. I feel pretty good about that.