Clipping volume, or clipping weight?

I prefer volume for routine measurement because it reduces problems with sand contamination

The standard for measuring how much a turf sward is growing is to take the dry weight of the clippings mown off the turf. This isn’t a realistic option for routine turf management because who has drying ovens? And who can take the time to separate sand from clippings to reduce measurement error? I find it easiest to measure the volume of the clippings. That’s a fast and easy way to measure the clippings. I don’t like fresh weight as much as volume, because fresh weight requires a scale, has the same problems with sand contamination, and some variation based on water in the samples that I suspect is higher with weight than with volume.

I was at Keya GC in Fukuoka in late May. On three of the greens at Keya, the volume and the fresh weight of the clippings are measured. I don’t recommend this! The only reason the maintenance staff are collecting these data are at my request, as part of a research project.

On May 29, sand topdressing was applied to the greens.

So what happened after that topdressing? Mowing was skipped for a few days. When mowing resumed, see how the ratio of fresh weight to volume spiked? And then took over a week to get back down to what it was prior to topdressing?

That’s the effect of sand contamination in the samples, and it is one of the reasons I prefer routine tracking of clipping volume to the tracking of clipping mass.