irrigation

Last year I wrote about manilagrass (Zoysia matrella) sod on highway medians in Thailand. I showed photos of a recently planted median, and explained why zoysia doesn’t persist in this environment when maintained without supplemental irrigation and regular mowing.

An easy way to relate inches of irrigation or inches of evapotranspiration (ET) to changes in volumetric soil water content (VWC)—that is something I could never figure out. I was thrilled to see the calculations shared by Bill Kreuser.

I’ve made a number of Shiny apps, and have collected them all on this new page. These are designed either to show a set of data, or more likely, to make some calculations with the inputs allowed to vary.

I’ve seen a lot of highways in Thailand. Highway medians are sodded with manilagrass (Zoysia matrella) as a matter of course (more about the cost of that below). I’ve seen some impressive vistas of this work in past years, but for safety reasons haven’t been able to get any photos.

When this question arrived, I thought I could respond by showing a blog post I’d written in the past with the answer. “What kind of adjustments would you recommend to do when trying to use the MLSN on a Calcareous sand green profile and irrigation with water saline water with 1500 ppm and Pure Dynasty Sea Shore Paspalum and pH 8?

I was talking with a golf course designer recently, and he mentioned that “zoysia starts to look pretty attractive because of its lower water use.” That led to a long conversation about how incorrect that statement is.

The normal range of calcium (Ca) in irrigation water is 20 to 60 ppm. That comes right from Penn State’s Irrigation water quality guidelines for turfgrass sites. Were you surprised by the previous post that worked out daily Ca use by the grass, and Ca added in irrigation water, to find that irrigation water was supplying 26 times more Ca than the grass was using?

Did you see where soil potassium (K) only went down by 1 ppm after 374 mm (14.7 inches) of rain? In that same comparison of pre- and post-rain samples, the soil calcium (Ca) went down by 26 ppm.

Yesterday I took a walk around a golf course in Chonburi, Thailand. It is three months into the dry season at this location; there has been negligible rainfall in Chonburi since the start of November.

Remember the Viridescent blog, with its 841 posts made from 1 January 2009 until I switched to this new site in 2017? I’ve summarized the top posts on that site by year, here, and today I checked the most viewed posts of all time.