How do we grow soil?
I was just asked a straight forward question.
How do we grow soil? or more precisely How to build a Living Soil ?
We start with silt, sand and clay. None of these are soil.
What we need are plants to convert this into soil.
Plants produce glucose through photosynthesis. Now we can use this to grow the soil.
Soil Building Components
1) Exudate is the sugars that the root tips are pushing out as they grow. This is what glues the silt, sand and clay together and causes good aggregation. It doesn’t matter what your soil base is. We are going to use the plants to literally convert whatever your base material is to soil. We add this Exudate to sand to make soil. We add it to silt to make soil. We add it to clay to make soil. Exudation builds soil from underneath which the C comes from the air.
Glomulin is also a soil building component added to the soil by the mycoryzza fungi. They exchange nutrients to the plants for sugar and convert it to glomulin which is a more stable form of carbon in the soil.
Source of Carbon
Residue Plant Material and Livestock Manure
2) The breakdown of plant material is also an important source of carbon in the soil. The Residue plant material we leave on the surface along with the manure left by the livestock are going to build a thatch layer.
Remember, all of this carbon came from the air as well.
This breaks down with the help of our soil organisms and turns into organic matter.
We are building soil from above ground this way. We just have to leave some residue on the surface, and we can grow the soil.
It also helps to reduce runoff and evaporation. A huge plus in repairing the water cycle.
3) Dead Roots also add carbon to the soil. As plant roots grow and die off, the residues are broken down by micro organisms to add carbon to the soil. And not just at the end of the season.
The act of Regenerative grazing speeds up soil building because when the plants are grazed off, the plant sluffs off some of it’s roots and then regrows them.
By grazing a pasture once or twice a season for a short time period, we actually build soil faster. We take carbon from the air and put it in the ground.
Regenerative Agriculture is not a recipe. We are looking at a whole system that works together to build soil. The livestock, the plants and the soil life, all working together.
As a producer, I grow soil. What do you grow?
– Steve Kenyon