Putting on my shoes, I was walking on a sidewalk older than my boots. When I passed over a small hole, which time made in the cement, I couldn’t resist. I took a step back and started watching it. I saw that the hole contained some pebbles inside it.
I also saw that some dry leaves “landed” there, carried by the wind. But, in the parts where there were neither pebbles nor dry leaves, a very lush green bush grew, so that the soil inside the hole was no longer visible (see photos, at the beginning).
When I experience simple moments of observing some detail of nature, it sometimes occurs to me to relate them to other similar moments already experienced. So, little by little, I collect what I call “natural principles”, as I identify, in different situations, similar patterns of behavior.
These notes that I make, fruits of observation, careful comparison and philosophical appreciation in search of truth, in ancient times, would be considered scientific. And it was, for many, many centuries. This one, from the broken sidewalk, I called the “ground cover principle”, which I called the healing law. Follows your statement and comments.
Principle of ground cover (law of healing):
“In order to protect life in its interior, when the soil is exposed, natural strategies come into play in order to cover it as soon as possible.”
The so-called invasive plants or simply “weeds”, are in reality highly specialized species in the horizontal occupation of open spaces on the soil surface, that is, where the soil was exposed.
Thus, they have efficient strategies for the dissemination and rapid germination of their seeds, which can remain viable even after several years in the soil. After germinating, rapid vegetative growth occurs even under the most diverse conditions of soil, climate and humidity.
All these factors plus the spatial orientation followed by this set of plants shows us, without any doubt, that the main objective of all this effort is to cover the soil as quickly as possible.
The effect caused by them is very similar to the rapid healing of a wound that was opened, not on our skin, but on the skin of our planet, that is, the soil. Therefore, the soil needs invasive plants or “bush” whenever it is attacked, because it can’t be exposed to the sun’s rays, nor the direct impact of raindrops or strong winds.
All of these factors would end up hampering and even making life and growth of the organisms that inhabit the soil and are directly responsible for feeding the plants inserted in it impossible. Without microbial life, without plants and subject to the terrible process of erosion, in a very short time the soil would die, become a desert, due to the relentless action of those climatic agents.
Invasive plants or simply “weeds” are, in this way, living beings that preserve the integrity of the soil environment, from the attacks made on it, especially those caused by the human species, which are the largest. Paradoxically, it is this preservation that guarantees the continuity of life on our planet, since we all depend on the soil to live.
Therefore, in our agricultural activities, despite the need to control the weeds that plague crops, we must do so in order not to completely eliminate these species, but only to reduce the number of their individuals in a way that doesn’t cause economic damage.
Its complete elimination from the face of the Earth would be the same as condemning everyone to extinction. The correct way to conduct an area where agriculture is practiced is to keep it at all times with complete vegetation cover, live or dead (straw).
It’s interesting to note that some time later, when we stop interfering in these spaces, shrubs and, years later, trees grow. When this occurs, the invasive plants, mission accomplished, begin to disappear, giving the responsibility of protecting the soil to those who, with their crowns, will perform the task more safely, on the top floor of the plant extract.
And as natural laws are manifestations of divine perfection in every detail, as these trees grow taller, they form on the surface of the soil below them, a carpet of fallen leaves to receive the drops of rainwater that they may drip from your canopy, thus cushioning the disintegrating impact they would cause if they hit the ground directly.
In tropical countries, the most studied and successful strategy for keeping the soil protected is the so-called no-till system or no-till system. This system, used on a large scale, consists of planting without the previous use of implements to revolve the soil.
The remains (straw) of the previous crop are kept on the soil surface, after being chopped up by the machines that harvested that crop. The next crop will then be planted without turning this straw, just scratching the soil and depositing the seeds in it.
As the vegetable remains in tropical countries are rapidly decomposed by the work of the climate, insects and microorganisms, it is necessary to plant, at least once a year, crops that produce straw or remains in abundance and that are slower to decompose.
That way, they should last until the next crop covers the land spaces. In the case of perennial crops, the same logic is maintained by sowing cover plants in between rows and brushing them when they grow, leaving residues spread over the soil surface.
Different species of cover plants, adapted to the conditions of the property, as well as equipment with which we can handle them, such as knife-rollers, brushes and brush cutters, should be the subject of constant attention.
Because the management of cultural remains, as well as cover plants, sown or spontaneous, are an important part of the business, since keeping the soil covered is essential for the proper functioning of the soil-plant system.
It is necessary to keep in mind the reasons why we need to keep the soil always covered with something alive or dead. The main ones are:
- Maintain an adequate temperature (18 to 28ºC);
- Protect the soil from direct solar radiation;
- Conserve soil moisture;
- Protect the soil from the impact of raindrops;
- Protect the soil from the action of winds;
- Control the germination of the seeds of invasive plants;
- Favor the biodiversity of soil organisms;
- Provide food for the living soil community;
- Keep soil particles aggregated, conserving their porosity.
These are fundamental points if we are to “create” and increase life on (or from) the soil. We should also not forget that the concern with permanent soil coverage leads us to produce a greater amount of plant biomass, an important condition to sustain the increase in the microbial community.
Antonio N. S. Teixeira
Executive Director – IBA