MLSN

We provide soil testing services for clients around the world through Brookside Labs, and have an active research program in the area of turfgrass nutrition, soil and plant analysis, and sampling methods.

My books about greenkeeping, turfgrass science, clipping volume, and MLSN.

Minimum levels for sustainable nutrition—MLSN—is a modern method for interpreting soil tests for turfgrass.

When I make nutrient recommendations, I recommend a quantity of each element that ensures the grass can get all of that nutrient that the grass can use. I also make the recommendation with a thought about the soil.

A couple of the science and statistics blogs I follow have recently shared AI-generated audio summaries of research papers. The ones I’ve seen were from Google’s NotebookLM. I hadn’t been using this, with most of my LLM (large language model) use over the past couple years being ChatGPT.

You may be familiar with the grammar of greenkeeping. That’s what I call the approach to turfgrass maintenance that focuses on growth rate. As I wrote in the preface to the book with that title:

Frank Rossi and Carl Schimenti had a discussion on the Cornell Turfgrass Show about soil testing, fertilizer, the Park Grass experiment, weeds, and some good ways to sell fertilizer. Also, that perennially hot topic of silicon.

Soil nutrient levels are dynamic. They change. In non-saline situations, the nutrient levels go down as the grass grows and uses some quantity of the soil nutrients.1 This is why the SLAN medium ranges seem so high, and why the MLSN method of soil test interpretation is so much more precise when making fertilizer recommendations for turfgrass.

One of the things I’ve tried to explain about MLSN is that simply taking a soil test and comparing the result to the MLSN value is not enough. One also needs to consider how much of an element the grass will use.

I listened to Joe Gulotti’s Talking Greenkeeper podcast with guest Daniel Palin about an MLSN trial on 9 holes, and a different method on the other 9 holes. You can listen to the show for the full story.