Early plowing of the Nile River floodplain made sense as new silt and fertility was deposited every year.

Kill your rototiller and save the soil (and planet)

It's time to prepare garden beds for planting.  The best planting soil is light and fluffy, full of air and with all plant residue removed.  Right?  That's what we have learned from industrial agriculture practices and rototiller advertising.  But these practices can reduce productivity and can be destructive to soil health and thus human health.  Over-tilling of farmland and garden systematically kills soil life and forces us to replace natural nutrients with chemicals fertilizers.

After over 200 years of industrialized agriculture and decades of "green revolution" chemical agriculture what is the health of our soils, and our farming and food system? Is farming more or less sustainable… economically, nutritionally and environmentally?  Are we behaving as if the health of the soil is directly linked to our health and that of the natural world?  Do we act as if the majority of the human-caused greenhouse gasses in the atmosphere result from cutting down forests, paving wetlands, overgrazing pastures and over-working farmland?  All these questions must be answered in the negative.

Fortunately, there is a growing movement in commercial agriculture called "no-till farming" that aims to mimic the way soils are actually formed.  We have learned that when soil is plowed, tilled and over-aerated to prepare for planting many negative affects result.  The biggest immediate problem is more rapid oxidation and loss of soil organic matter leading to lower fertility and more erosion.  This is followed by degradation and disruption of soil life, the trillions of soil biota (bacteria, microbes, mycorrhiza, fungi, earthworms, etc) that make up the soil food web.  There are helpful and harmful soil biota in terms of supporting plant and thus animal and human health.  How we treat our soil determines the balance of good or bad soil life.  Tilling makes this balance less healthy.

 

Tilling also can cause soil compaction creating a physical barrier for a healthy soil food web and accelerating soil erosion where topsoil is washed or blown away due to loss of plant cover, root systems, and soil texture and life.  Estimates for the US are that we have lost more than half our topsoil mainly due to poor agricultural practices and excess tilling over the past century, jeopardizing our entire food system.  And the costs are ‘externalized’, we do not account for them.  The estimated annual costs of losses related to soil erosion exceed $45 billion.

A rough calculation of current rates of soil degradation suggests we have about 60 years of topsoil left globally, and less in the US. Almost half of soil used for agriculture around the world is labeled as either degraded or seriously degraded (the latter means that 70%+ of the topsoil, the layer allowing plants to grow, is gone). 

No-till farming avoids many of these effects by growing crops without tilling. Crop residues or other organic matter are retained on the soil surface and seed sowing and fertilizing is done with minimal soil disturbance.

No-till farming increases organic matter retention (thus building soil fertility naturally) while also increasing the amount of water that is absorbed and retained in the soil. This in turn increases the amount and variety of soil life. The most powerful benefit of no-till is improved soil biological fertility, making soils and thus plants healthier.

 But perhaps the bigger benefit of no-till farming and other and other regenerate farming practices that build soil carbon is the capture and sequestration of atmospheric CO2. A  new report by the Rodale Institute notes that:

 

"We are at the most critical moment in the history of our species, as man-made changes to the climate threaten humanity's security on Earth. But there is a technology for massive planetary geo-engineering that is tried and tested and available for widespread dissemination right now. It costs little and is adaptable to local contexts the world over. It can be rolled out tomorrow providing multiple benefits beyond climate stabilization.

The solution is regenerative farming (and gardening).

Simply put, we could sequester more than 100% of current annual COemissions with a switch to widely available and inexpensive organic management practices, which we term "regenerative organic agriculture" (and gardening)."

No-till farming and gardening is the #1 soil regenerative solution.  Do you really need to power up that tiller this spring?

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