Mowing and Rolling Frequency and a 50% Savings on Daily Greens Maintenance.

When I finally started collecting data in a meaningful way I began to find that there is all sorts of questions that I can ask the data that I may not have previously thought of. Why would I want to ask new questions that I previously didn't need? Well, there are many things that I can do to improve our operations but it is often difficult to quantify how effective these strategies are.

One of the things I recently asked of my equipment data, was to summarize how often we mow and roll our greens broken down by month and year. There are many decimals because we sometimes skip mowing specific greens and my equipment database can determine the percent of the total area maintained each day. For most this is probably needlessly complicated but nonetheless I calculate it because I can.

I do not have data before 2019 because I wasn't the superintendent before that time, but I estimate that the greens would have been cut 200 times and rolled 100 times based off annual equipment hour meter readings from the maintenance records.

My maintenance strategy has been to mow less and roll more for the past decade or so and I was finally able to achieve this at my new golf course in the past few years. Disruptions to budgets and from Covid made anything beyond basic survival difficult before 2022.

Anyway, I can also quantify how many days each year we did mechanical greens prep with either a roller, mower or both. In the summer we aim for daily greens prep and we do generally achieve this. 

As you can see, we use equipment to maintain our greens for 170-221 days each year or 50-60% of the total days. Things like snowfall, pandemics, and having to lay off your entire staff in August, can impact how often we can maintain the golf course haha.

The table below shows the ratio of rolls to mows broken down by month and year. You can see that in 2019 we were mowing more than rolling for most months. This was because our older roller was a piece of shit. We got a new roller that summer and were able to increase our mowing to rolling frequency. Since 2021 we have been able to roll more than we mow almost every month. My general rule is roll 2 times for every mow and not more than 4 times for every mow. Weather and available staff are big factors and I will not simply blindly follow this rule as you can see. If I can get the desired conditions with less resources, I will. I don't roll to maintain a ratio, I roll to keep costs down and conditions up.

We can then compare our mow and roll data to the total days we maintained the course data to see if there is a trend in maintenance practices. Simply looking at the annual totals doesn't give the full picture because it doesn't take weather into account. I bypass weather data and just assume that every day that the weather is good for play, we are maintaining the greens with equipment. The amount that we need to mow is highly dependent on how much grass we are growing. Less grass, less mowing. I'll share this in a future blog post because yes, I can calculate the average clipvol per mowing broken down by month, obviously haha.

Now we can see that we are actually mowing less than before. We now cut on half of the days that we maintain our greens with equipment and roll 70% of the time. We mow and roll on 26% of the days. All of these figures are trends in the right direction when it comes to my experience.

I'll take it a step further because...why not? All of the data so far is sort of cool but it doesn't really mean much, especially to budget planners.

We can divide the operational costs of maintaining our greens (labor and fuel) by the number of days we maintained the greens each year to determine our daily cost. As you can see, we are spending about half of what we used to. Our total costs of operating the equipment are down due to using the cheaper roller more often and we are maintaining our greens more often. This data doesn't include the cost of equipment maintenance or ownership although I suspect that if this data was included, it would further increase the savings we are now realizing. We are using our more expensive equipment less and our cheaper equipment more. If we use our triplex mower as much as we used to, we could get about 5 years or service out of it for a cost of the lease and maintenance of $14,000 a year. As we can now double it's lifespan that cost goes down to about $7000 a year. Our roller costs us $4500 per year over 5 years. We can get better green speeds (discussed in a future post) and reduce our relatively fixed costs by $2500 a year in leases and maintenance by rolling more and mowing less.

This all makes sense and most people's intuition will tell them that this is the case. I am bad at guessing and like to have solid evidence that what I am doing is the best for my situation. I can confidently say that our maintenance strategy on greens has reduced costs substantially.

You might also be thinking that cost reductions like this might result in higher costs for fungicide and fertilizer. Nope. I've managed to cut those in half too! This makes sense, rolling has been shown to reduce disease like dollar spot and fusarium patch and mowing less stresses the plant less as long as you aren't scalping. I don't know exactly why we required less fungicide in recent years through. It's virtually impossible to pin it on any one thing. In reality it is likely a combination of everything that I can and cannot control. We had a good year and the trend is promising but only time will tell if it lasts.

There are, of course, many other things that go into putting green maintenance. Sand, irrigation, other general maintenance and all of those things aren't covered in this data. Regardless, the daily operational and chemical costs have been drastically reduced.

None of this matters though, if we don't take playability into account. That is our main goal when it comes to using equipment on our greens. In an upcoming post I will compare the type of equipment use to average green speed to see if we are still able to maintain adequate playing conditions with these cost saving changes.