The Haney test is intended to select robust soil biological activity even if the overall percent organic matter isn’t great. But it’s an open question of what “enough” biological activity is, so interpreting tests like the Haney can be difficult.

The USDA describes soil carbon farming as “the use of specific on-farm practices designed to take carbon out of the air and store it in soils and plant material.”

One of the most challenging aspects of successfully managing nitrogen is the fact that nitrogen from fertilizer can be lost from the soil before the corn crop can take it up.