Using light energy to protect covered turf

Having your turf covered for a concert or other special event is stressful for even the most experienced turf manager. A new protection system that the manufacturer says reduces or even prevents turf deterioration is now available and has been used successfully.

When grass is covered for periods greater than 2-3 days, physiological and morphological responses to reduced irradiance begin to manifest themselves in turf grass as follows: 1) shoot etiolation characterized by reduced pigment, 2) decreased evapotranspiration, 3) reduction of nonstructural carbohydrates, 4) reduced tillering and shoot density, 5) longer internodes with reduced stem diameter, 6) increased leaf length and decreased leaf width, 7) thinner leaves, and 8) decreased root growth. With all these processes happening at once or in close succession, the plant is weakened and there is little hope for a healthy turf after an event.

RGT has developed the new tool, LED Turf Panel, to combat these stresses. The panels provide Photosynthetically Active Radiation (PAR) via light emitting diodes to the grass during the event and also serve to spread the load from traffic to the grass. Providing light energy to the plant while it is covered helps to maintain its health and integrity and, thus, improves the playability and safety of the turf surface after an event.

The manufacturer says the system is easy to set up and teardown with a small crew and waist high T-wrench. Power is provided to each panel through an intergraded plug that is tucked away during installation. When panels are linked together they create a non-slip, temporary floor free of trip hazards and provide a uniform surface for building stages, walkways, and vehicle roadways. Panels may be pre-assembled on pallets in one, two or four panel sections and moved on small carts for fast installation. Panels may also provide illuminated walkways and VIP and refreshment areas that may be linked to show production lighting controls.

Here are some comments from users:

“The LED panels were great. We tried them on the outsides of our playing field for a series of concerts that included two Kevin Hart shows and a One Direction concert. The panels sat underneath the delay towers that were built 8 days before their getting off the field. I spoke with John Royce [RGT president] and decided to give them a try. The set up was not difficult, and similar to any other flooring system. When we pulled the flooring after being down for 8 days, the grass was still green. It was a little off color compared to the rest of the field but after a few days you would have never known we had the grass covered for that long of time. I would recommend the LED panels. Our situation was a bit extreme for the amount of days covered and we were still ok.”–Tony Leonard, Director of Grounds, Philadelphia Eagles

“Our Taylor Swift concert trial was actually our third trial of these LED panels; we also used them on a trial basis in late fall of 2014 for a smaller concert and over the winter. We were highly encouraged by the results we saw in the fall of 2014, so we were ready to give them a full test under the stage towers for the Taylor Swift show here in Houston (during baseball season) September 9, 2015.

“We installed the LED panels under the towers at approximately 3 AM Monday as they were being built, and the panels were lit at that time to the purple color, which is a combination of the red and blue colors that are used by the plant for photosynthesis. The panels stayed on the turf continuously through noon Thursday, so a total of 81 hours give or take for the order they were installed and removed.

“We had panels under four different areas of the stage, and all four ended up with different treatment levels of light due to real-world electrical challenges, including breakers tripping, cords being damaged, stage crews unplugging cords, and concert production crews moving cords.

“We saw turf benefits under all the panels, but especially the panels that ran for 81 hours straight. That picture has been shared quite a bit, I believe.

“I was also encouraged by the fact that the grass did not regress after it was uncovered. Often times in turf management, we are able to create a false sense of a beautiful stand of turf using growth covers or other protective covers, only to find later the grass regresses as it re-adjusts to the harsher outdoor environment from the protected growth environment we created. We did not see any negative effects or regression in the days or weeks after we uncovered the LED-treated turf.

“Installing the panels is very similar to installing any other drivable floor product with the notable exceptions of having to connect the power cords between each panel and having to plan out the power circuits for the floor well in advance.

“Overall, the results were exactly what we hoped for; our grass under the LED panels was in better condition coming out of the concert than it was going in. Anyone who has had a large stage with towers on their field for more than a couple days can attest that normally the grass under the towers is the most damaged and yellowed, and takes the longest to recover from the concert. Our turf under the Taylor Swift towers was green, vibrant, strong, and TV-ready as we pulled off the LED panels.

“I remain excited about the future with LED grow lights for use in stadium turf management, and we expect to use these LED panels more going forward here in Houston.”—Dan Bergstrom, Senior Director Major League Operations, Houston Astros