This is the World Organic News for the week ending 18th of November 2019.
Jon Moore reporting!
Decarbonise the air, recarbonise the soil!
A step in thinking is required to move from Chemistry to Biology. Chemistry is a reductionist science, by and large. A big thing is interrogated and the smaller things making it up are discovered. Molecules, atoms, subatomic particles, quarks and things and if it ever finds a way to be tested experimentally, tiny little strings that are the basis of string theory.
Biology proceeds in a similar way from kingdom to phylum to class, order, family, genus and species. However, when biology is observed in an ecosystem, we find emergent properties. That is, things that only occur when species interact.
The 1 square metre garden I planted for the RegenEarth Living Soils Conference back in September 2019, demonstrates this even at this scale. One of the cultivars planted was a mixture of lettuce seedlings. A week after planting I noticed a few slugs on the lettuce leaves and some damage to broccoli and spinach too. In week two I harvested some of the outer leaves of the lettuce. They had holes from slugs and a few still on the leaves. I flicked the slugs off to the chooks who gratefully accepted them.
A week later when I went to harvest again, the slugs were gone. The chooks are prevented from entering the garden by a wire mesh fence so it wasn’t them. Other birds can enter the garden from the air so they may have come to our rescue but I failed to observe this activity. The other explanation I have is the interactions of the seedlings as they grew. The lettuce are surrounded by mizuna, baby beetroot and the broccoli. Possible some chemical interactions between the plants created a micro environment unsuitable for slugs. Certainly the weather remained damp and conducive to slugs but the slugs were gone.
Time is an important factor in this. If I’d reached for some sort of chemical response to the slugs, i’d have added another layer of complexity but not one which was conducive to natural repair. The picking of the outer leaves might also have removed the preferred food source for the slugs. Again a natural solution. The point I’m trying to make is don’t react immediately to every disharmony in the garden. Let the systems do their thing, even though, in this case, I had no idea what or even if the slugs would be dealt with, they were.
As I discussed in Episode 166 Mycorrhizal Communities and How to Keep Them Alive., we know very little of the interactions of this Kingdom, the fungi with the plant kingdom. What we do know is that interactions occur. The majority of the research has been in forest settings but given the eruption of mushrooms across our pastures, I’m inclined to think their role in promoting and supporting annual plant species is greater than we may realise. As discussed in Episode 166, mycorrhizal species do much to regulate the flow of nutrients in forest ecologies, not just within tree species but across them.
For the mycorrhizal species to do their thing requires a level of stability within the environment. Hedgerows have traditionally filled this requirement, even if we didn’t this ourselves. Hedgerows themselves create more complexity, adding biennials, perennial shrubs and trees to the farming ecosystem. From my observations it seems clear that a certain amount of tree cover creates conditions for more intensive pasture growth and opportunities for grazing management of a regenerative type.
The approach I’ve been discussing is based upon the regenerative model. To compare this with the industrial model is enlightening. Soil biology is rarely mentioned. The pH of the soil, the nutrient “deficits”, the N,P, K requirements of the extremely hybridised seed, these things can be measured and rely upon our understanding of the chemistry of the inputs to produce a return. The key part of that is: “Inputs to Produce a Return.”. And all these inputs are costs to the farming/horticulture enterprise.
What this system doesn’t take into account are the services provided, for free, by the biological systems. Systems, the chemical/industrial system not only doesn’t factor into it calculations but systems it actually destroys. Now I don’t think we have a conspiracy here, I think we have the law of unintended consequences at work. And farmers spotted what was going. Huge amounts of nitrogen were available after WW2 and when applied to fields, pastures and paddocks they increased vegetative growth enormously. The observant farmers noticed the drop off in earthworms and other biota but the increased returns attracted most. There was though, as I have mentioned before, a Fuastian pact going on. All this extra growth for the mere sum of about 1% of the top soil each year.
In the first ten years or so, this doesn’t seem like much when it’s dripping away, little by little. After 70 years, people are, understandably, concerned but not as many as I would have hoped. Still with the right seeds and chemical inputs, things will grow in subsoil as a sort of paddock wide hydroponic system.
A biological approach requires a different mindset and relationship with soil, pests and returns. A well run regenerative farm may not be as profitable as a chemical one in that one yer a decade when water and sunlight matches hybrid seed needs and chemical fertiliser loads. It will though, be much more profitable and sustainable during the drier years, the years when things don’t match the textbook requirements of the hybrid seeds. In effect a complex biological approach evens out the more extreme fluctuations over time, giving a more reliable cash flow.
Now I know no farm survives real well after five, six, seven years of drought but some appear to be. I’ve added a link in the show notes to an ABC piece entitled: Regenerative agriculture finds solid backing as decades of success show renewal. Well worth a read, if only for the before and after photos. Link.
My takeaways from my reading and hands on experiments around this subject? We need to place soil biota at the pinnacle of everything we do on farm or in garden. There is so much we just don’t know about soil ecology but what we do know points us in very definite directions. We have a choice, lower cost natural systems that have evolved over billions of years or high cost “industrial” solutions which destroy soil, release carbon dioxide and crash with each drought.
Decarbonise the air, recarbonise the soil!
My co-host on RegenEarth, Rich and I are in the process of preparing RegenEarth’s second season of podcasts and I’ll let you know when they are roaming free on the interwebs. In the meantime you might want to listen to our short season one and subscribe so you’re ready for when season 2 drops.
Thank you for listening and I’ll be back next week.
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Regenerative agriculture finds solid backing as decades of success show renewal