After grass is mown, the remaining aboveground plant material is called verdure. The Turfgrass Information File describes verdure as the “layer of green living plant tissue remaining above the soil following mowing.
I’ve been thinking about measuring organic matter and about the quantity of sand required as topdressing for any turfgrass surface.
For samples taken near the turfgrass surface, I would like to measure the mass loss on ignition, and call that the total organic matter.
In a previous post, I mentioned that I’ve been thinking a lot about sand.
I expect that sand is required for managing playability of sporting surfaces. I’ll writing in terms of golf course putting greens in this series of posts, but the principle applies to any turfgrass sports surface.
How much sand is required as topdressing? And how does one determine what that amount should be? The amount of sand necessary must be the amount required to optimize playing conditions for the most days out of the year, and simultaneously must be the amount required to manage the soil organic matter at the desired level.
Irrigation water quality, salinity, gypsum, and sodium—I’m not even going to mention the problems that bicarbonate doesn’t cause—are topics that are sure to stir up some discussion. I shared a couple old blog posts last week, related to sodium, sodicity, and gypsum, and sure enough, there were all kinds of responses, with much of it taking a tangent from what the blog posts were about.
Last week I spent a few days in Fukuoka. I was there for the 103rd Japan Amateur Golf Championship. On the the morning of July 5, I recorded a short iron shot landing on the 16th green at the host venue, Keya Golf Club.
A recent conversation about putting surfaces in Japan led to discussion of topdressing amounts and frequency.
The Greenkeeper 2018 has course maintenance summaries for 17 courses in Japan. I mapped the locations of those courses by zip code.
PACE Turf have prepared this spreadsheet that takes inputs of average temperatures and a maximum monthly topdressing rate, and gives outputs of estimated monthly and annual topdressing sand amounts.
It is a metric version of this:
There’s a new spreadsheet available from PACE Turf that uses the temperature-based growth potential to estimate the quantity of sand required as topdressing. They wrote:
“To get a rough idea of how much sand to apply over the course of the year, we have developed a simple spreadsheet that uses growth potential (GP) as a guide, and a maximum sand application of 150 lbs dry sand/1000 ft2 per month at maximum turf growth.