fertilizer

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

A lot of turfgrass nutrition research gets done with fixed rates of fertilizer applied on a fixed time schedule. It always seemed normal for me to fertilize this way. Here are a few examples.

I talked with Frank Rossi today on the ATC Doublecut. You can watch or listen to the show at the links. We discussed potassium (K) fertilizer, and why there are still recommendations for so much more K than the grass can use.

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.

One of the many ways to learn is through conversations with industry veterans. Their wisdom about how turf is managed now, and how it was managed in the past, can be invaluable.

The usual way of thinking about soil nutrients and turf quality is something like this: when the amount of a soil nutrient is low, the turf quality won’t be as good as it would be if that nutrient were more abundant in the soil.

Remember the experiment I wrote about that evaluated a lot of different fertilizer “programs”? The control treatment in that experiment was urea, monoammonium phosphate, potassium sulfate, and ferrous sulfate. That urea-based treatment, which Dr.

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.

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.