After gathering various opinions about the benefits of higher cutting height on turf during the summer months; shade to the soil, establishing deeper roots, and improving photosynthetic surface what would your expert opinion be on a recommended grass height?

Meet the challenge of coaches and mowing heights

Q: Our game soccer field is a Kentucky bluegrass/rye mix. We regularly topdress our native clay soil with sand and the field was originally constructed on very productive farm land. The competitive soccer season is August through November and April through May. During the non-competitive season, the hot days of northwest Ohio, there is very little action on the field and we are looking for a recommendation on grass mowing height. Our coaches prefer to maintain the field at its playing height of 1 inch. Our grounds staff prefers to let the turf grow to 2 1/2. After gathering various opinions about the benefits of higher cutting height on turf during the summer months; shade to the soil, establishing deeper roots, and improving photosynthetic surface what would your expert opinion be on a recommended grass height?

Jim Elsasser

Associate Athletic Director for Internal Affairs

Bowling Green State University

A: Mowing height has been thoroughly researched and the relative differences between tall and short cutting heights are well known, as Jim indicated. Justification for a taller mowing height comes through deeper roots, more plant food making photosynthetic surface area, better ground shading that reduces weed competition and lowers soil temperature and heat stress. A follow-up phone call indicated that in past years they have in fact been raising the off season mowing height to 2 1/2 inches in June and July and then gradually reducing the mowing height back to 1 inch over a 3-week period in August. This process has worked quite well and the coaches have been pleased with field playing quality through the fall soccer season.

The old adage “if it ain’t broke don’t fix it” fits nicely here and the grounds crew certainly seems to have figured out how to make a premium field when it is show time and the season is on. But in this case they are being asked to see if they can up their game a bit by making the field game ready even during the off season. I don’t try to second guess coaches and if they are taking time to pay attention to the field then that is a good thing from my perspective because if they are giving some thought to the field then it is a good opportunity for you to educate them about your job and managing grass.

Despite some of the stereotypes about coaches, they are intelligent, hardworking, and passionate people that want every advantage to succeed at their job; to win games by maximizing player performance in a safe and attractive setting. Coaches that beat the field into the ground with endless repeated use and no regard for the playing surface only to complain that you are not doing your job of providing adequate turf cover feeds this negative stereotype of coaches.

That’s not the case here. The coach wants the field mowed at the game ready mowing height of 1 inch during the off season in June and July. I’m not sure why but let’s assume it’s a good reason to improve his program. One reason that surprised me at this level of college play is that coaches are always recruiting and they want the facility to look at its best even if it is for the simple reason of spending a few minutes with recruits on the field during the off season. Whatever the reason it is important to communicate exactly what you want and why and then be ready to compromise when common sense prevails.

I happen to think field quality and recruiting is a big deal and that more sports turf managers need to include this as part of their field management awareness plan. A recruit kicking the ball around on a slow 2 ½-inch field can leave a lasting negative impression that just doesn’t get the job done. As sports turf managers we sometimes focus only on the health of the grass and forget to realize that we are part of the team, with the same goals to win, by recruiting the best players possible, and letting them maximize their talent in a safe and attractive arena.

I sound like a broken record but when we all get on the same page then coaches, sports turf managers, and athletic directors have a better chance of knowing when to compromise. If it is not a big deal to the coach then they should compromise because all the science indicates that taller mowing during the summer is better for the grass. But we also know that if they were forced to play soccer during the summer then the grounds staff would certainly find a way to manage the field at 1 inch during the summer. The athletic director must weigh the importance of expending the resources to keep the field at a 1 inch summer mowing height; more labor, more attention to irrigation, more fungicides, and more risk of losing some grass during the summer or starting the fall season with less than desirable turf.

It’s hard to argue against the taller mowing better grass strategy but here is a compromise that could work to everyone’s advantage and improve the overall quality and stress tolerance of the grass. Primo is a plant growth regulator that slows vertical leaf growth and reduces mowing frequency so this will cut back on summer mowing labor. More importantly less expenditure on leaf production shifts carbohydrate utilization to improve turf in several areas; denser turf, smaller divots, and more roots. Another bonus is that after growth regulation wears off there is a rebound period of extra growth that can be timed to occur during the playing season to speed recovery from traffic. The net result of using Primo is that it will allow the coach to have a field mowed at one inch during June and July and it will also help the grounds crew reduce the need for mowing while at the same time improve summer stress tolerance of the grass. Usually I find worn-out grass in the middle of high use fields but in this situation I’m seeing middle ground with good grass all the year round.