Putting green speed and its variability

I spoke about within-green and between-green variability in putting green speed using the standard deviation of multiple measurements as a statistic. The median standard deviation for both within- and between-green variation is about 0.3 feet. That's approximately 4 inches. I suggest that greenkeepers continue to report a single number as the green speed. I also suggest that greenkeepers occasionally take multiple measures of green speed, on the same green and on multiple greens, and then calculate the standard deviation. If the standard deviation is more than 4 inches, and if resources are available to do the work, I suggest doing some maintenance that may reduce the variation. That could include measuring the #ClipVol of putting surfaces, verticutting, topdressing, rolling, applying a growth regulator, adjusting mowing height, etc. The measurement can be made again to evaluate the results of the changed maintenance practices.

Transcript

1. Putting green speed and its variability Micah Woods Chief Scientist | Asian Turfgrass Center www.asianturfgrass.com 29 November 2018
2. Fuji Classic GC
3. Today’s outline 1. Green speed as explained and as reported 2. Measurements I’ve made of green speed 3. Measurements under tournament conditions 4. Dispersion of ball roll
4. The Stimpmeter instruction booklet
5. First sentence: “One of the most significant aspects of a golf course is the uniformity of its putting greens.”
6. Second sentence: “Variations in speed, whether from one green to the next or on different parts of the same green, can do more to negate a player’s skill than can ragged fairways or unkempt bunkers.”
7. Orchard Golf & CC
8. PGA Catalunya
9. Keilir GC
10. Yufuin Kogen GC
11. 2. Measurements I’ve made of green speed
12. Brooks GC, Japan
14. Koshigaya GC with Dr. Eric Reasor & Dr. Jim Brosnan
16. “The average golfer seems unable to detect a 6-inch variation in green speed … Therefore, a 6-inch variation among greens is probably a fair definition of consistency on a golf course.”
17. What is normal standard deviation within greens?
19. What is normal standard deviation between greens?
21. What does a standard deviation of 0.3 feet look like?
23. 3. Measurements under tournament conditions
24. Keya GC
25. Keya GC
26. Measuring tools at Keya GC
30. 4. Dispersion of ball roll
31. Balls rolled by “Perfect Putter”
32. Balls marked and measured
33. Dispersion measured
34. Dispersion measured
39. What happens when greens get really fast?
40. Hazeltine GC, 2016
41. Hazeltine GC, 2016
46. More information at www.asianturfgrass.com