This is the World Organic News for the week ending 15th of June 2020.
Jon Moore reporting!
Decarbonise the air, recarbonise the soil!
This week we continue our exploration of the “Chaos Garden” idea. We finished last episode with some quotes from Dr Christine Jones on the importance of photosynthesis.
Today we explore the suggestions Dr Jones makes to enable photosynthesis to operate at its maximal effect.
- Green is good – and yearlong green is even better.
- Microbes matter!!
- Diversity is not dispensable!!!
- Limit chemical use
- Animal integration
Green is Good
To the first 1. Green is good – and year long green is even better.
This seems almost too obvious to discuss but there are nuances I hadn’t considered.
Quote:
While every green plant is a solar-powered carbon pump, it is the photosynthetic capacity and photosynthetic rate of living plants (rather than their biomass) that drive the biosequestration of stable soil carbon.
End Quote
Photosynthetic capacity relates to the number and size of leaves in a given area and the amount of sunlight falling on them. Photosynthetic rate is the level of light to sugar conversion.
So we’re looking for full ground cover of leaves and for those leaves to convert the light falling on them to sugars at the highest rate possible.
Podcast footnote:
Most leaves are green. That means they are absorbing the blue and red ends of the colour spectrum but reflecting the green. That means there’s a huge chunk of available light not being used for photosynthesis. If plants absorbed all the available light we won’t be seeing jungle green but jungle black.
End Podcast Footnote.
These photosynthetic effects can be in the leaves of plants with a $30 tool called a refractometer which measures sugar levels. (There’s a link to a Youtube video explaining how it’s all done.) Mine is winging its way here as we speak. The sugar levels reveal how well we are doing on the capacity and rate metrics. I’ll be using this tool as I run various experiments in levels of chaos in the garden systems.
Now green all year applies as much to gardeners as it does to broad acre growers. Fukuoka’s method of sowing the next grain crop before the last one is harvested is a great way to ensure this happens.
In a garden situation it can also mean sowing before harvesting but will more likely mean having starts ready to immediately fill the harvested gaps in the garden. This requires more work. Have a space for seed starting and the infrastructure to set it up but I suspect the increased food quality from the plants being part of a continuously growing garden bed will more than cover the extra effort.
You may remember the quote from last week re: nutrient quantity and quality from last week. If not, here’s a quick reminder.
Quote:
Soil dysfunction also impacts on human and animal health. It is sobering to reflect that over the last seventy years, the level of every nutrient in almost every kind of food has fallen between 10 and 100%. An individual today would need to consume twice as much meat, three times as much fruit and four to five times as many vegetables to obtain the same amount of minerals and trace elements as available in those same foods in 1940.
End Quote.
I think it’s really worth the effort to experiment at the garden level to move those measurements back to where they were.
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Microbes matter!!
Long term listeners will know this is an obsession of mine. The good Dr’s too.
Quote:
The significance of the plant-microbe bridge in transferring and stabilising carbon in soil is becoming increasingly recognised, with the soil microbiome heralded as the next frontier in soils research. One of the most important groups of plant-dependent soil-building microbes are mycorrhizal fungi. These extraordinary ecosystem engineers access water, protect their hosts from pests and diseases – and transport nutrients such as organic nitrogen, phosphorus, sulphur, potassium, calcium, magnesium, iron and trace elements including copper, cobalt, zinc, molybdenum, manganese and boron – in exchange for liquid carbon. Many of these elements are essential for resistance to pests and diseases and resilience to climatic extremes such as drought, waterlogging and frost.
End Quote
The fact we are only just grasping the consequences of killing the soil microbiome is mind boggling. The need to re-establish healthy soil biology is crucial. One of the benefits is growth in the depth and fertility of the recovered soils. The UN suggested in 2015 that we might have only sixty harvests left if we continue to destroy our soils at the rate we are. (Link here.)
Clearly there are better ways than the cookbook, over hybridized, chemically and irrigation water supported agriculture pushed by shareholder run ag chemical and seed companies like Bayer, Syngenta et al. More on the M.O. of these companies briefly under point 4 and in greater depth next week.
I am pretty sure we can take the need for a biologically diverse and healthy soil as a given.
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Diversity is not dispensable!!!
This is where last week’s chaos garden ideas fit in. Those are examples of diversity taken to an extreme but not as extreme as natural systems.
The benefits from diversity become obvious from a simple level of complexity. Companion plants, dual cropping, alley cropping and so on are examples of increasing diversity over monocultural practices. That such small changes can create such huge returns points to the importance of establishing and maintaining diversity. As I’ve said elsewhere in this podcast, the greater the complexity in a biological system, the greater the stability, counter intuitively for those of use born and raised since the Industrial Revolution.
Dr Jones does give us all some hope and somewhere to start:
Quote:
However, it doesn’t need to be complicated. Something as simple as including one or two companions with a cash crop can make a world of difference. Indeed, it is becoming increasingly common to see peas with canola; clover or lentils with wheat; soybean, pigeon pea, faba beans, mung beans or vetch with corn; flax with chickpeas; buckwheat and/or peas with potatoes … and so on. Monoculture will hopefully soon be a thing of the past.
End Quote
There are ways to start growing the soil biology and in a way that allows us to take little steps towards our goals.
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Limit chemical use
Need I say anymore?
I’ll let Dr Jones put in a way I’ve intuited before but never seen written down so succinctly:
Quote:
No amount of NPK fertiliser can compensate for compacted, lifeless soil with low wettability and low water-holding capacity. Indeed, adding more chemical fertiliser often makes things worse. This is particularly so for inorganic nitrogen (N) and inorganic phosphorus (P). An often overlooked consequence of the application of high rates of N and P is that plants no longer need to channel liquid carbon to soil microbial communities in order to obtain these essential elements. Reduced carbon flow has a negative impact on soil aggregation – as well as limiting the energy available to the microbes involved in the acquisition of important minerals and trace elements. Lack of trace elements increases the susceptibility of plants and animals to pests and diseases.
End Quote
Another example of the misplaced use of chemicals I heard this week comes from the Cover Crop Strategies Podcast, link in the show notes. Basically the situation described was one of slug infestation in maize crops. One section of the maize crop had been planted with neonic treated seeds to stop insect predation on the seeds. The other section hadn’t been so treated. Observation showed the slug predators arrived in both plots but the slugs in the treated area took up some of the neonics and were poisoning the predator insects. The untreated area was not affected by the slugs as the predators did their job or perhaps more accurately, exploited their niche and were able to reproduce, the slugs were not able to do so.
More on this next week where I’m taking a deeper dive into unintended consequences.
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Animal integration
I’ve pointed out in other episodes the importance of this. Animals and plants co-evolved together. As diversity increases so too do available niches. The point of animal integration is to use the animals to maintain the ability of plants to grow. Regenerative grazing, large mobs, moving quickly across the landscape appears to be best for the animals and the plants and, most importantly, the soil. In Dr Jones’ words:
Quote:
The way livestock are managed has a significant impact on soil function. In actively growing perennial pastures, it is vitally important that less than 50% of the available green leaf be grazed at any one time (Fig.1). Retaining adequate leaf area reduces the impact of grazing on photosynthetic capacity and enables the rapid restoration of biomass to pre-grazed levels. Significantly more forage will be produced during the growing season – and more carbon sequestered in soil – if pastures are grazed ‘tall’ rather than ‘short’. In addition to maintaining photosynthetic capacity through management of leaf area, the height of pasture has a significant effect on moisture retention, nutrient cycling and water quality.
End Quote
How this works at the garden level takes some creative thought. Chicken tractors, a few ducks, geese on larger areas are all options. As are rabbit and/or guinea pig tractors. It just requires, as I say, some creative thought. The benefits in complexity are many. Putting green matter through an animal also creates “compost” much more quickly than building a pile.
So remember the five principles:
- Green is good – and yearlong green is even better.
- Microbes matter!!
- Diversity is not dispensable!!!
- Limit chemical use
- Animal integration
And start applying them to your garden, smallholding or broad acre farm.
There’s a link to a Udemy course in the show notes entitled “Growing a No-Dig Garden” if you’d like some more formal assistance in your gardening. You can also go to or send people to Episode 207 where I discuss growing a quick response garden to get yours happening swiftly.
Remember in this unusual time, if we put in the ground work now, we can all change the world, even if its only a little bit to start with and we will begin the process of:
Decarbonising the air, recarbonising the soil!
Thank you all for listening and I’ll be back next week.
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LINKS
Growing a No-Dig Garden on Udemy
Or copy and paste this link:
https://www.udemy.com/course/no-dig-garden-course/?referralCode=7393F372D1748E4A4282
email: podcast@worldorganicnews.com
Transcript: https://worldorganicnews.com/episode218/
Most Farmers in the Great Plains Don’t Grow Fruits and Vegetables. The Pandemic is Changing That. https://civileats.com/2020/05/12/most-farmers-in-the-great-plains-dont-grow-fruits-and-vegetables-the-pandemic-is-changing-that/
Light Farming: Restoring carbon, organic nitrogen and biodiversity to agricultural soils Christine Jones, PhD Founder, Amazing Carbon http://amazingcarbon.com/JONES-LightFarmingFINAL(2018).pdf
International Year of Soil Conference
http://www.fao.org/soils-2015/events/detail/en/c/338738/
[Podcast] No Insecticide Means More Predation, Less Slugs