I love watching The Masters and especially enjoy seeing near-perfect greens and the exacting putts they demand. I also appreciate the amount of effort it takes to produce putting surfaces and the resulting green speed.

After checking several sources, the consensus seems to be that the green speed was 12 feet + on Sunday. Just what is green speed? How is it measured? Why measure it? What variables can affect it? I’ll attempt to address these questions and hopefully give you a better understanding of green speed and the factors that influence it.

Green speed can be defined as the averaged distance a golf ball rolls when released from a Stimpmeter at a controlled velocity. The United States Golf Association (USGA) introduced the Stimpmeter in the late 1970s to enable tournament officials to measure ball roll subjectively in an effort to promote uniform and consistent speed between greens on a given course. They also came up with the following Speed Charts that are presented for general information only.

Speeds for Regular Play

8’6” Fast

7’6” Medium-Fast

6’6” Medium

5’6” Medium-Slow

4’6” Slow

Speeds for Championship Play

10’6” Fast

9’6” Medium-Fast

8’6” Medium

7’6” Medium-Slow

6’6” Slow

The USGA’s “Stimpmeter Instruction Booklet” (http://www.usga.org/turf/articles/management/greens/stimpmeter.html) states that the Stimpmeter is an extruded aluminum bar, 36 inches long, with a V-shaped groove extending along its entire length. It has a precisely milled ball-release notch 30 inches from the tapered end.

It goes on to say that the Stimpmeter is a simple, accurate device that allows one to make standard measurement of, and place a numerical figure on, the speed of a putting green. It has proven to be an invaluable asset to the game of golf and a helpful management tool for the golf course superintendent, but it is not intended for course comparisons.

There are many variables that influence green speed, chief among them being environmental factors. Rainfall and high humidity result in slower speeds while dry and warm conditions cause faster speeds. Seasonal variations can contribute to ball roll distances of greater than 1 foot, while daily fluctuations during optimal growth periods can be 4 to 8 inches. The speed can become faster or slower, depending on conditions.

I’ve also discovered that there are many maintenance practices that affect green speed. Lowering the mowing height, to a point, will increase ball roll because there are fewer grass blades to slow the ball. Likewise, decreasing or limiting nitrogen fertilizer inputs makes for greater speed by decreasing leaf thickness and/or stand density. Rolling greens as part of an overall program can increase ball roll 4 to 10 inches without causing compaction on high sand content greens like those at the Brickyard.

One of the most interesting research studies I’ve read, from the University of Arkansas and Michigan State, shows that rolling greens has a greater impact on green speed than lowering the height of cut. The study also found that mowing frequency could be reduced without a decrease in ball roll distance if the greens were rolled on the days mowing was skipped.

This mowing/rolling regime produced the most consistent day-to-day green speeds. Light, frequent topdressing causes an initial decrease in speed but then a 4- to 8-inch increase as the topdressing works into the turf canopy. Core aerification impacts surface smoothness, and unless the holes are filled can decrease green speed for many weeks.

Plant Growth Regulators (PGR’s) are used to help increase speed by slowing the rate of growth and eliminating or reducing annual bluegrass seedhead formation.

All of the above factors, plus the type of soil, turf type and amount of thatch contribute to green speed and must be considered when developing management programs. But when everything comes together and results in fast, smooth and resilient greens like Augusta National just presented, it’s awesome!

Jeff Stuart

Course Superintendent

Brickyard Crossing