Soil ecology is an enigma to me and I marvel at its complexity and beauty. It’s a symphony of infinite living organisms and it’s a farmer’s job to be the conductor. Every new insight I gain is an exciting step toward that goal.
I recently attended a regenerative agriculture workshop where the basic premise was that there is a kind of spectrum of ecological systems. Some of the information presented seemed at odds with other workshops that I’ve attended, but who doesn’t love a bit of dissonance to get you thinking? I missed the first two hours (#farmerlife) so there may be some gaps, but here’s what I learned.
The spectrum I mentioned above sits with a woodland at one end and a grazing land (prairie) at the other. The woodland system favours ectophyticfungi and endophyticbacteria. That is, fungi that lives separate to and outside of the plant roots and bacteria that live inside the plant roots. The grazing land tends in the opposite direction, in that here you find more endophyticfungi (invisible and living inside the root hairs) and ectophyticbacteria (living close to but separate from the roots).
Whichever direction you are heading in, has implications for the kinds of plants that you might want to encourage. The workshop was aimed at graziers so let’s go a little further in that direction. A healthy grazing land will have a diversity of herbaceous plants (predominantly sedges and grasses). 20 minutes after these grasses and sedges are grazed, they shed all of their remaining sugars. This is because of the kind microbes present in the soil, as mentioned above. They need a big boost of Nitrogen in order to regrow and they’re going to get it from ectophytic bacteria. This is the beautiful part of regenerative farming. Nitrogren is being pulled out of the air and put back into vegetable matter – see my previous blogabout nutrient cycling.
However, this is where it gets contentious. Forbs are a different class of herbaceous plant and operate in a different way. Just like woody shrubs and woodland trees, they have a symbiotic relationship with microbes that are opposite to that of a grazing land. Therefore, if you encourage too many forbs into your grazing system, you are working in the wrong direction and fighting a losing battle. With too many forbs present, once grasses and sedges are grazed they will rely on the ectophytic fungus instead of the ectophytic bacteria, effectively short-circuiting the function of a grazing land. The fungus will mine the soil for the Nitrogen as opposed to the bacteria pulling it from the air.
Most predominant assumption is that a forest is the ultimate succession of a prairie. Take a prairie and improve it by planting trees and eventually creating a forest. The workshop facilitator posits that it is the prairie that is, in fact, the ultimate. That you take a woodland and add animals to improve it. That’s not say that one should remove a forest to graze animals, but that the functionof a grazing land is more efficient at cycling nutrients due to the kind of microbes it favours.
I must now consider which kind of system am I aiming for? In which direction am I headed? As an orchardist I might tend towards a woodland but what if I am grazing cattle among the trees? What if I am grazing poultry? All I can do is learn as much as possible, act, observe and repeat.