The science behind great playing surfaces

Turfgrass research, field observations, and practical management advice, published continuously and archived for two decades.

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Oct 26, 2026 Members only

Green firmness and OM4

In July 2023, I spent a week traveling west across Japan, starting near Tokyo and ending near Fukuoka. Along the way, I collected measurements…
Oct 25, 2026

Green firmness and topdressing sand coefficient of uniformity

The coefficient of uniformity (Cu) is a value that indicates how similar the particle sizes of a material are. If the Cu is a…
Oct 23, 2026

Organic material accumulation rate

We find it useful to calculate the accumulation rate of organic material for a few reasons. First, knowing the accumulation rate allows us to…
Oct 17, 2026 Members only

Photo of the week: elephant footprints

There is a real disease called elephant's footprint (caused by Rhizoctonia cerealis). That disease is almost exactly the size of a real elephant's footprint,…
Oct 15, 2026 Members only

Sand topdressing measurement

When insufficient sand is applied, the sward doesn't perform as desired. In fact, it may fail completely. When too much sand is applied, the…