weather

Did you know there are different ways to calculate the average daily temperature? A new PACE Turf update discusses this. In that update, I looked at the daily minimum and maximum method, and compared it to the average of hourly measurements method.

If you’ve got some organic matter in the soil, then you will get some nitrogen (N) that the grass can use from it. This is called mineralization. As the organic matter decomposes, some of the N that was in the organic matter is converted into inorganic forms in the soil.

I’ve written before about ΔGP. That’s read as “delta G P” and it is the difference in the cool-season and the warm-season growth potential. Specifically, it is the cool-season GP first, then the warm-season GP is subtracted from that.

I use a method based on clipping harvest and normal leaf nitrogen content to find the estimated nitrogen harvest. I adjust this based on species, because there are differences in the clipping volume to dry mass conversion based on what type of leaf we are working with.

This note below, about the temperature-based turfgrass growth potential (GP), has been sitting in my blog_posts.org1 file for a while now, as one of those topics to write about sometime. When I read the note I jotted down when I created this entry, I realized I wouldn’t have to do much to turn this into a blog post.

I’ll start with a tautology. Warm-season grass species grow, and are used as turfgrasses, in locations with warm temperatures. Where it gets interesting is the interaction of light—specifically the photosynthetically active radiation (PAR)—with temperature, and with water supply or drought stress.

On a recent trip to southern Europe, I was walking on a fairway and looking down at the grass. I’d seen some bermudagrass (Cynodon) fairways and did not notice any dollar spot.

A previous post showed photosynthetically active radiation (PAR) data in units of daily totals—the daily light integral (DLI). That post included a chart with a locally smoothed regression line through it.

I’ve been using the NASA POWER agroclimatology data for a few projects. I get the data using the convenient nasapower R package by Adam Sparks. There is also a web-based map data access viewer.

The median blog post on this site in 2019 got 244 views. And there were a few up around 1,000 to 2,000 views. There were these top 10 that everyone read.