Picture 1, Sunday 24th Sept.: The day after the Penn State game, the Koro Field Topmaker removed the stabilized perennial ryegrass field. The field was in its 4th season and was playing well but over those 4 years, fine mineral particles (silt & clay) had accumulated on top of the stabilizer and had created an anaerobic and unstable surface (Sherratt, Street & Gardner, 2005). Traditional management of the fine mineral layer (aerate & topdress) had not been an option as it would have destroyed & buried the stabilizer. The fine mineral particles probably came in as a result of the extensive construction work around the stadium and by other natural sources (wind, rain). Textural analysis of the stabilized layer showed that the sand had been contaminated with around 11% silt & clay. As a side note, the Koro has revolutionized the field renovation business as it can remove a whole field and leave the surface graded in just a few hours.
Picture 2: There are not too many mid-season renovation options - big roll thick-cut sod is really the only way of producing a playable field in a very short period of time. This particular sod was from Cygnet Sod in NW Ohio and was grown on soil (sandy loam). The turf component is 100% Kentucky bluegrass and is 2 years old, so has a 1/4-inch thatch layer and moderate rhizome development. The sod was harvested 1.75 inches thick, 48-inches wide and 35 ft long. The sheer weight of big-roll, thick-cut sod is what gives the field instant playability.
Picture 3: Big roll, thick-cut sod. In this particular instance, the sod was grown on soil. Sand-based sod (>80% sand by wt.) is also available but would not have offered the same stability at such short notice. Sand-based sod needs some establishment time for roots to offer stability. A lot of the sand from the back of the sod can also be lost during transportation. Soil sod was chosen because instant results were needed. One of the concerns with soil sod is that it has the tendency to stay saturated once it gets wet, creating a poor environment for root growth and it could possibly become muddy & unstable during a rain game. This will dictate future field management practices.
Picture 4, Monday 25th: The first sod roll gets layed. Around 650 rolls were layed - 26 truck loads with 25 rolls per truck. Pre-sod, micro and starter fertilizers were applied.
Picture 5, Tuesday 26th - Friday 29th: As each roll was layed in a staggered pattern, the seams were topdressed with sand and hand-syringed with the hoses to prevent the seams for drying out. One of the critical processes is making sure both the longitudinal and latitudinal seams fit tight, so that when they shrink they do not cause gaps in the sod.
Post-sodding, the field was rolled with a 2,000 lb roller. The roller straddled the seams. The field was mowed periodically as the sod was layed & rolled. Sodding was completed on Friday 29th at 6.30pm.
Picture 6, Saturday 30th: The entire field was injected with sand. Four DryJect machines were used to produce sand channels through the sod on 3 x 3 spacing. The purpose of the DryJect is to create sand channels that bypass the fine-textured sod layer. In the event of a rain game, the sand channels will help to shed surface water and keep the field playable. From an agronomic standpoint, the channels will also provide a healthy , aerobic environment for root growth & gas exchange.
Picture 7: The DryJect system is an intense renovation process that injects sand channels through the sod layer but then leaves the playing surface intact and instantly playable. For that reason, it is a popular renovation procedure in golf green management.
Picture 8, Saturday, 30 September - Sunday 1st October: Post-sodding practices start. This includes lowering the mowing height (the sod came in at 2.5-inches), applying starter fertilizer, topdressing with the same sand used in the DryJect, and painting lines & logos. Any seam discoloration will also be addressed with paint. The next home game is October 7th. If rain is forecast before any of the remaining games, tarps will be used to keep the sod as dry as possible.
Picture 9: The OSU Stadium agronomy team includes Assistant AD, Don Patko, Field Superintendent Brian Gimbel and his two assistants, Brian Blount & Brent Packer, and Dr. John Street & Pam Sherratt. Brian Gimbel (pictured on the new field)and his team of staff & students have worked tirelessly during the renovation process & we cannot speak highly enough of them. Working from dawn until dark most days they have worked extremely hard to get this field ready for the Buckeyes. We really appreciate their dedication & hard work & hope that the media & the team do the same. GO BUCKS!
P. J. Sherratt, J. R. Street, and D. S. Gardner. 2005. The effects of Biomass Accumulation on the Playing Quality of a Kentucky Bluegrass Stabilizer System Used for Sports Fields. Agron J. 97: 1107-1114. Authors: Pam Sherratt & John Street
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