I was honored to speak at the 40th Congress of the Asociación Española de Greenkeepers in Seville.

Organic matter

In the 2016 article “Managing Organic Matter in Putting Greens,” Adam Moeller and Todd Lowe wrote this:

“Putting greens might be temporarily soft or inconsistent for many reasons, such as recent rainfall, but when there are chronic issues the underlying problem is often excessive organic matter just beneath the putting surface.”

I led one seminar about organic matter in putting green soils. The slides are here.

I called the presentation “Thinking Differently.” I used to recommend the standard, or textbook, amount of coring and topdressing. I now recommend:

  1. Be aware of the textbook recommendations, which are 15 to 20% surface area removal by coring each year, and from 12 to 15 mm of sand applied each year.
  2. Measure the growth rate.
  3. Measure surface firmness.
  4. Measure soil water content.
  5. Measure the surface layer organic matter.

And then adjust to get the desired results.

Putting green speed

The stimpmeter instruction booklet starts with these two sentences.

“One of the most significant aspects of a golf course is the uniformity of its putting greens. 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 bunkers or unkempt fairways.”

In my presentation about green speed—the slides are here—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.