The data says…
Recently I had a data conversation with a fellow golf course superintendent. As she asked me questions about the data I collect and how to get started, I realized that up until and including the Ryder Cup in 2016, I wasn’t collecting, or analyzing any amount of data. I was flying blind! The playing surfaces for that event were wonderful, praised by the media, members of both teams and the Hazeltine membership. But while the conditions were great, the number of disruptive practices performed in the months leading to the event was substantial. At the time, I was certain the end had justified the means. Today, with the assistance of data and time, I am certain many of those means (disruption) were unnecessary.
As golf course superintendents, we know any time we raise the bar, we also create the new standard by which we will be judged. As the 2017 golf season dawned, my mind was geared toward meeting the standard we had set during the previous season’s Ryder Cup. The goal was to provide a golf course that came as close as possible to Ryder Cup conditions, for a maximum number of days each season. Given the season-long effort involved, I wasn’t sure how we were going to replicate those conditions in a normal season, but I knew knowledge was key and data was going to have to play a part.
My data revelation started with the tracking of putting green clipping volumes, eventually progressing to daily stimp meter measurements, STRI smoothness ratings, and #OM246. I am not going to hit on all of these data, but should you desire, the links will allow you to explore each topic in more detail. With this post, my goal is to point out how data has pointed us toward achieving the highest standard of daily putting conditioning and how disruption jeopardizes those standards. I will get into specific practices deployed, or not in upcoming posts. This post is simply about what the data says.
All charts created by and used with the permission of Dr. Micah Woods
Chart 1 above is a scatter plot showing average daily stimpmeter measurements on the y-axis and the same day’s average STRI smoothness rating (bobble) on the x-axis. The bobble test is a rating taken by watching the ball roll across the surface and is done as I am measuring greenspeed. Unfortunately, the bobble test is a data point I only began tracking in 2021. The scale is 1–10, but on good greens, a rating below 6 is unlikely. My goal is to have as many days with a stimp of 11+ and a bobble of 8+ as possible. As I speak with members and pay attention to their comments, then cross-reference with data, I have found an 11/8 stimp/bobble combination to be the point at which our golfers find the greens pleasing and thus I have come to think of 11/8 as our low-end goal for daily play. As noted on the chart, the 2021 golf season featured 91 days of 11/8 or better conditions. However, if the goal, as mentioned above, is to maximize the number of days with Ryder Cup-like conditions, then we must strive to go beyond a stimp/bobble of 11/8. My experience tells me a stimp/bobble of 12/9 is Ryder Cup-level putting conditions; a level we achieved 46 times during the 2021 season.
As time goes on, I suspect we will use days above 11/8 and 12/9 as targets for improvement. If we achieve 91 days above 11/8 in 2021, can it be 100 or more in 2022? Knowledge is certainly power in aiming to get there and as you will see below, there is plenty of room for improvement.
Chart 2 shows the same data by month. In Minnesota, the golf course is closed and mostly frozen and snow covered from November to mid April. Spring weather is often cloudy and cold, leaving the grass slow to grow. One can imagine how it takes some time for conditions allowing for 11/8 conditions to materialize. In 2021, April and May had a total of five days with 11/8 or better conditions, while June and July featured only two days without putting conditions of 11/8 or better. The tighter the pattern of dots, the more consistent the conditions. The further toward the top right corner, the faster and smoother the conditions. There’s no doubt weather impacts our ability to provide the very best conditions and once summer hit, our conditions were generally consistent until the end of the season; with the exception of August.
Chart 3 shows the bobble test score (y-axis) over the entire season. This chart has been annotated to note specific events during the season. Three times, the bobble test started below 8, then rose to 9+. The common denominator with each of these events was-sand topdressing. We apply sand late in the fall, which lingers into the spring and does not completely disappear until the grass begins to grow in earnest. On May 11th, we applied a medium-heavy topdressing and on August 3rd, we aerified and backfilled with sand, leaving a similar medium-heavy finish. Each time sand was applied, there was a corresponding drop in the smoothness of the putting surface. With each drop, there was period ranging from 15–30 days, before the smoothness climbed back up and leveled off at 9+. The recovery to 11/8 and eventually 12/9 level of putting surface conditions, were negatively impacted each time sand was present on the surface. The conditions were even more dramatically impacted by the August aerification. The process used took too long to heal and the impact on playing conditions is obvious in the data.
Post 4…The paradox of progress!