Do you remember when we recently discussed the advantages of tilling or plowing in the ground ? We also said that if it was done frequently it had drawbacks. From these problems that arise from the abuse of soil tillage, the doctrine that is based on conserving the soil in a “natural” way arises. That is, zero tillage or minimum tillage, where the objective is to keep the properties of the soil intact. Let’s see what it’s about.
ADVANTAGES AND DISADVANTAGES OF NO-TILLAGE
It is known as conservation agriculture, and it seeks to try to take advantage of the conditions that the soil offers, without modifying or, at least, minimally, the structure of the soil . If the plants grow in it, it is because it meets the minimum conditions and therefore does not have to undergo modifications.
We can call it zero tillage or direct seeding. In other words, the work that the farmer has to carry out begins directly with the sowing and not with the previous preparation of the soil, or the bottom fertilizer.
Today, large-scale agriculture rejects this method and plows the ground once the next crop is incorporated. Sometimes with subsoiling to bury previous crops.
Surely, when we mention the advantages of this no-tillage technique we will mention some that were also discussed in the reasons why the soil should be plowed. It would not be logical that two opposing techniques can achieve the same results, right?
Well, it is somewhat more complicated since given the complexity of the soil , the improvement of one variable implies the improvement of another or, the worsening of others. Everything is linked and everything influences.
Better, let’s see the benefits of no-tillage and then discuss one by one. If you want to make a comparison, you can take a look at the reasons for plowing the soil .
REASONS WHY YOU SHOULD KEEP THE LAND UNTILLED
SOIL NITROGEN CONSERVATION
As we already said, there are several ways to fix nitrogen, and not only do some microorganisms. The atmosphere , through rain, for example, also manages to fix nitrogen.
By plowing the soil, its volatilization occurs, and consequently, the loss to the atmosphere. This reduces the amount of nitrogen available to the plants once their planting begins. For this reason, plants turn to organic matter , which means that it is gradually diminished in the soil.
LABOR AND FUEL SAVINGS
Undoubtedly this is a compelling reason for large farms and entrepreneurs who are dedicated to the world of agriculture. It is saving the passage of tractors to till the soil and to pay it initially, in addition to the daily wage that the driver will have to pay and the time it takes to carry out said operation.
Believe it or not, all the variables involved in the use of agricultural machinery are well studied. From running speed, weight, lap time, tractor slippage, power, etc. They are many hectares and the choice of one system or another supposes a considerable saving.
However, that does not mean that agricultural machinery is not used under no-tillage. With this we would be saving about 80% of the machinery pass, but it will have to be used to collect (in some cases), apply products such as fertilizers or chemical products.
PRESERVATION OF SOIL STRUCTURE
No doubt. If the earth has a good structure, why modify it? The old saying “better known bad than good to know” can also be applied, although we would not entirely agree either.
If you get good yields with zero tillage , perfect. There is nothing to say. But if the soil has drainage problems, the structure is not good or there are not good levels of organic matter, it is necessary to consider making a modification of all these properties, by means of the plow.
Done right, this ‘new’ composition of the soil will last for many years and it will be possible to return to minimum tillage.
WHY IS CONTINUOUS TILLING NOT RECOMMENDED?
Remember when we said in the reasons for plowing article that you don’t have to do it very often? Here we tell you why.
FOR SIMPLE ECONOMIC REASONS
As we have said, if plowing work is reduced , fuel and labor are saved, the deterioration of machinery is reduced, etc.
BY DEGRADATION OF THE SOIL STRUCTURE
A soil that is not in tempero has more possibilities of being degraded by the action of the tillage. Therefore, it is advisable to do it only when the soil is in this state.
BY COMPACTING THE SOIL
How much does a tractor weigh? All that weight is transferred to the ground and compacted. In fact, although more archaic techniques are used, such as shooting animals, they also have a great compaction power , forming the “typical work soles”.
IN THE LONG RUN, THE ORGANIC MATTER CONTENT IS REDUCED
Due to the volatilization that we have mentioned and due to the short-term reduction in the activity of microorganisms. Although with tillage the plant remains of the previous harvest can also be buried (in very high proportions, higher than 90% ), it is also true that the mixture is not homogeneous.
SOIL EROSION PREVENTION
With intensive tillage, there is a disintegration of the land that, in the long run, can acquire the consistency of fine earth . In addition, with the elimination of the residues of the previous harvest, the action of the wind or the water intensifies, being able to generate erosion problems.
WHAT DRAWBACKS DOES ZERO TILLAGE OR MINIMUM TILLAGE BRING?
As we saw in the advantages and disadvantages of the soil plow , we are going to do the same with this soil conservation system.
On the one hand, agricultural machinery is not used as often as tractors. However, by making fewer passes, you tend to need more modern or specialized machinery, or larger. Logically, the greater the length of work you have, the fewer passes, which can mean a significant initial expense for the farmer.
IF THE SOIL IS NOT GOOD, IT WILL STILL BE BAD
After this failed attempt at a pun, what we want to communicate is as we discussed in the previous article. If the soil does not offer good characteristics, they will have to be modified. The faithful followers of this doctrine will continue to cultivate even though the conditions of the land are not good. Production will be reduced.
ALTHOUGH ORGANIC MATTER INCREASES, IT MAY NOT BE ENOUGH
The advantage of zero or minimum tillage is that, by having a good level of microorganisms, they manage to increase the levels of organic matter in the soil. However, with the plow crop remains were incorporated into the soil, or organic matter was buried as a bottom fertilizer.
WEED AND PEST AND DISEASE CONTROL
Without the use of machinery, the elimination of competing weeds, as well as the control of pests and diseases, is complicated.
At the garden or orchard scale, it is possible to carry out a control without the need to use large machinery, but in large areas where the farmer is playing a lot of money, choosing the correct option is not so easy.
Our opinion, not necessarily the good one, is to opt for an interspersed use of these two techniques. Neither should you choose an agriculture based on tillage, nor on zero tillage. Is there a middle ground? Yes, conservation agriculture.
This term includes the application of a series of techniques that allow to improve or at least conserve, the natural resources available in nature. The land, considered one of the greatest natural resources, because it is a non-renewable resource, must be conserved in the best possible way.
However, this does not mean not modifying it at any time, as there are cases where its “non-alteration” implies an “alteration”.
If it is true that conservation agriculture pursues minimum tillage , but not no tillage . There are times when it is necessary to make some physical soil improvements, the change of which will be noticeable in a positive way for years to come.