soil test

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.

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

A project that investigated soil nutrient levels of good-performing turf all over the world.

Measure exact topdressing effect, and requirement, by checking total organic material by depth.

Let’s start with the take home message. Soil nutrient levels vary. When there is a lot of variation, the average as we usually calculate it—as the arithmetic mean—can be higher than other methods of calculating the central tendency of the test results.

Remember, the OM246 test measures the total organic material, living and dead. A 4 cm diameter core of fine-bladed manilagrass with extensive living plant material below the surface. If the grass has a more extensive root system, or a more extensive rhizome system, the OM value measured on an OM246 test will go up simply from there being more total organic material in the sample.

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.

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.

This is one of the many interesting things I’ve been working on recently. A standard soil test for turfgrass is taken to a 10 cm depth (4 inches below the soil surface).