Creating and maintaining Soil Integrity does more than increase yields, quality and health. Good soil is integral to a healthy environment. A healthy Natural Environment is a system that promotes diversity, a system where Nature in all its myriad of forms can flourish, a system that mitigates the carbon cycle in our favor. We want to develop a Natural System that is complete as possible, as close as possible to healthy ecosystems in the wild.
To this end Natural farming advocates inoculating the soil with Indigenous Microorganism IMO, and mulching the soil to provide microbial habitat and feed, promote water retention, and suppress unwanted weeds. Tilling the soil is to be avoided. Furthermore crops should be grown as a polyculture, employing companion planting & plant diversity. The property should have hedgerows and fencerows for wildlife and to create more edges in the system. And integrated pest management should be practiced.
One of the biggest ways you can create and maintain soil integrity is to not till the soil. This is important for several reasons.
Water & Air needed for plant survival
Microbial habitat destroyed with tilling
The Underground Communication & Defense Network destroyed
Worms drill down up to 7 meters deep
Microbes are a sink for Carbon & Nitrogen
Microbes are 80% water
A plant that is 100cm high, grown in untilled earth, will have a 100cm root system.
The same 100cm plant grown in tilled soil will have a root system that is only about 20cm deep.
A good soil is crumbly, not a pile of dust nor hard like stone. It has texture and air pockets. The need plants have for water is obvious, but they also need oxygen for the root systems. Soil creatures also need oxygen. With poor soil structure rain and surface water can be excluded and become runoff. Or, the soil can become supersaturated with water which chokes out oxygen and promotes anaerobic organisms leading to rot and decay. Plant root systems and soil organisms need air and the proper amount of water. Soil with good texture provides these. Tilling destroys the texture leading to problems with both water and air.
A soil with crumbly texture and air pockets provides soil organisms with habitat. The health of the soil is directly correlated to the amount of living organisms. Those organisms need space and organic matter in which to live and grow. Destroying the structure of the soil directly kills soil microbes, leaving organic matter to putrefy since air pockets have been destroyed. Anaerobic conditions in soil can lead to pathogens, which can not only be dangerous to people but can prevent good soil ecology from returning. The killing done by tilling is more than just the act of tilling itself.
Running vehicles over soil will have the same effect, destroying the soil texture through compaction. Even soil under human pathways can be compacted and suffer. Design your system so that soil compaction from vehicles and walking is limited.
UNDERGROUND NETWORK & WARNING SYSTEM
Interesting discoveries have been made recently showing how plant communities communicate over large distances, largely using the mycelia of fungi. Tilling destroys these communication network. One of the things plants communicate though these Underground Networks is the appearance of pests and other dangers. If the soil communication network is widespread it can broadcast the appearance of pests and disease from great distances. This gives plants time to mount chemical and other defenses long before the threat reaches them. Let your plants keep their Emergency Broadcast System.
It is well known that plants produce more than they need, exuding excesses from the root systems in a sticky sugary substance called root exudates. Root exudates give soil texture by clumping soil particles together. But the exudates also serve another function. Through the network of microbes and soil creatures the valuable resources found in root exudates can be shared in the community. While we think of plants and competing for resources, the truth is most plants, as long as they have enough space, air, and sunlight, act cooperatively. This complex communal ecosystem is destroyed by tilling.
LET NATURE DO THE TILLING
Nature is very good at building good soil structure and integrity. Worms, for example, are capable of tunneling up to 7 meters deep! As a worm tunnel down their excrement, or worm castings, carries microbes and this takes the whole of soil microbiology farther & deeper. Worm castings soften rocks and can be used to turn rocky soil into good soil. Besides aerating the soil and breaking down rocks, soil organisms bind soil particles together, creating a dark, rich, crumbly soil, and developing the underground communications system. By inoculating soil with a healthy microbial biology using Indigenous Microorganism IMO, and by mulching the soil to house and protect the microbes you create the conditions for the soil microbes and small animals to do the tilling for you, in a deeper more sustainable way. Topsoil will be built up, and resources such as water, nitrogen and carbon are maintained, even increased.
TURN SOIL INTO CARBON & NITROGEN & WATER SINKS
The exoskeletons of soil organisms are a sink for Nitrogen and Carbon. The more microbes in the soil means the greater the carbon sequestration. Untilled soil means that, Carbon & Nitrogen are kept in the soil rather than released to the atmosphere where they can affect global climates.
Soil Microbes have been shown to hold 11kg per 0.1 hectare* of Nitrogen N, and 70kg of carbon C. The amount of carbon lost to the atmosphere by tilling is significant, on the order of 70kg per quarter acre. (*0.1 hectare = 1000m2 = 1/4 acre)
Additionally, microbes are 80% water. Destroying soil microbiology means the loss of a great amount of water held in the soil. A lot of the improvements in water retention made by organic gardening, permaculture, and regenerative techniques work because they keep the water held in the soil intact. Increasing the microbial levels in your soil will increase the water stored in your soil.
Soil structure and integrity do not come in a package. They can only be built by Nature, by soil communities. Tilling destroys all the benefits of good soil structure and integrity. It destroys air pockets, creates soil erosion. It destroys the mycelial networks used for communication & defense. It releases the carbon, nitrogen, & water locked in the soil into the atmosphere, and it kills the soil organisms that turn dirt into soil.