BCGSA Professional Development Days, December 7–8, 2023


You can download the slides here:

Questions during the seminar

One of the questions was about different methods for soil test P. There’s a section about this in the MLSN cheat sheet. For example, an Olsen P equivalent to the “standard” MLSN is 6 ppm. Bray 2 is 30 ppm. If you are using those extractants, you can substitute 6 for Olsen or 30 for Bray 2; the standard Mehlich 3 MLSN for P is 21 ppm.

For more about this, see the blog post Converting between soil test extraction methods.

We also discussed nutrient availability by a water extraction (saturated paste). I find conventional soil tests adequate for assessing nutrient availability. If one wants to check if the grass is getting the nutrients, then I recommend checking the leaf tissue. Doing a saturated paste (water) test will always give lower nutrient values, sometimes quite low, but that does not mean that the grass will not be able to obtain enough from the soil. I’ve written about this in a blog post with the title “Available” calcium, soil pH, and fearmongering.


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