soil test

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.

Normal range of test results Soil test phosphorus (P) is present across a wide range in golf course putting green rootzones. I looked at ATC data from putting greens for the past five years.

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.

The Green Section Record (Volume 62, Issue 4) has an interesting article by Chris Neff making a case for year-round soil nutrient analysis. Specifically, he wrote that: To adequately make decisions regarding these crucial fertilizer applications, it is imperative to conduct soil sampling throughout the year to assess soil properties and current nutrient levels, which play a pivotal role in the overall health and performance of the course.

I was collecting OM246 samples at sunrise on a busy golf course near Bangkok on Tuesday, and I remembered that I was going to update the OM246 sampling instructions. That update is now made, so when you download the sampling instructions, you’ll get version 0.

Dried soil samples from the Park Grass experiment at Rothamsted that were collected in 1876. I recommend drying soil samples before sending them to the lab for testing.1 There are a few reasons for this:

I was teaching a seminar about the distinction between soil organic matter (humus) and total organic material, and how to make use of those test results, when this question was posed:

I’ve written about the rapid change in soil pH that can occur in sand rootzones, especially when turf is grown in a tropical climate. That potential for soil pH and other soil parameters to change substantially is one of the reasons I recommend annual testing of turf grown in sand rootzones.

My advice is to test for soil nutrients at the time of the year when nutrient levels are likely to be at their lowest. In temperate climates in which there is some precipitation during the summer, then this is an autumn timing.

Once upon a time, I presented the manganese availability index (MnAI) on soil reports. I also put a line at 45. When the MnAI was less than 45, I recommended Mn application.