Soil Aggregation – Keeping What You Gained

March 4, 2024

One of the foundational principles in regenerative agriculture is that every acre of land needs a living crop growing in it as much of the time as possible. A living crop is photosynthesizing – it is capturing sunlight and using water, then producing sugars and pumping some of them out the roots and into the soil to feed the soil microbes.

Soil aggregation, the structured soil that we all desire, does not happen if you don’t have roots deep into the soil. Think of it this way: Sugars are produced through photosynthesis. Some of these sugars are sent out through the roots to feed biology. Biology feeds at the roots to digest these sugars, and – here’s the important part – they reproduce rapidly when they have enough food, water, and oxygen. The biology and mycorrhizal fungi then produce glomalin and biotic glues, which then “glues” soil particles together to produce soil aggregates. This cycle is then repeated over and over again – creating more-deeply aggregated soils over time – deeper each year until the roots no longer go deeper.

A critical piece to think about: Just because your soil has become well-aggregated doesn’t mean that it can’t become compacted again. Soil aggregates are only stable for 30 days. If there are no sugars being pumped into the soil, the active carbon levels are not being replenished, and eventually the soil life doesn’t have enough to eat – so, they stop maintaining the soil aggregates. So, the first critical piece is to feed the soil life continuously with the sugars produced by living plants and also soil algae.

But, of course, there are other pieces as well:

• Too much tillage – tillage disrupts the soil biology and mycorrhizal fungi. It disrupts the earthworm channels. It can cause the soil to crust over with the next rain;
• Too many chemicals – chemicals (especially in large and continuous amounts) create an environment that is toxic to soil biology;
• Overgrazing, or leaving the soil bare, especially in hot summer months;

I suppose there are many other pieces as well.

The reality is that the system is very complex and yet so very simple all at the same time. It’s the way it was designed. It was designed to work. The simple way to make it work is to follow the principles. We don’t have to understand all the in-depth and complex things that happen when we follow the principles. We’re not that smart. We just need to practices the principles so that we can harness that power and so nature can shine.