Given the numerous beneficial roles soil biology plays in crop production — including nutrient cycling, water-holding capacity and disease suppression — more no-tillers want to learn how well their soil biology is and what they can do to improve it.

Lance Gunderson admits that it’s “very difficult to measure and evaluate what the ideal soil biology should be or what it currently is.”

But the director of Soil Health & New Test Development at Ward Laboratories in Kearney, Neb., says new tests and other techniques have been developed in recent years to help growers answer those questions. At the 2016 National No-Tillage Conference in Indianapolis, Gunderson presented some of the “soil health” tests that are available, their intended purposes and how to interpret their results.

Phospholipid Fatty Acids

The fatty acids a doctor might tell a patient he or she should be getting more or less of are the same types of fatty acids that can be found in the soil.

Gunderson explains these fats have a lot of carbon that, just like in humans, provide a high source of energy for the microorganisms in the soil.

“When a microorganism dies and the cells break down, those fats are quickly eaten by the other living microorganisms,” he says. “So that’s why we’re able to use phospholipid fatty acids (PLFAs) to help us quantify what’s still alive in the soil.”

CALCULATING CARBON. The Solvita test is used to measure how much carbon dioxide is generated for a 24-hour period. The more…