In the field of agriculture there are factors that are crucial. One of them is the importance of keeping soils healthy, a premise that agricultural producers are extremely aware of, especially since that guarantees that their crops and their harvest offer quality products that meet the expectations of the agricultural market as well as the demands of consumer. To achieve this goal, farmers implement some strategies such as cover crops.
According to Jeff Graybill, Agronomy Professor at Pennsylvania State University, cover crops are an essential component of a sustainable agricultural system and today, more and more farmers are using them to protect the soil, regenerate it and, as environmental assistance. It is usually used when the main goal is to protect soils that are cultivated out of the normal growing season of the plantation. Related to this topic, we invite you to read about how to prepare the soil for harvest.
Uses and benefits of cover crops
Their uses are diverse and have numerous benefits that are important for farmers, such as the fact that they prevent soil erosion and keep products such as fertilizers and components that come from animal manure, so necessary for farms with high-yield crops, from filtrating into streams and groundwater, which could imply contamination hazards.
The use of cover crops restrains the nutrients of fertilizers, preventing them from draining from the roots and leaves of the plants.
Once the season passes and cover crops have fulfilled their function of protecting the soil structure, the nutrients that have been stored are transferred to the main crop bringing many benefits such as:
- Guarantee soil and water quality
- Provide extra feed to livestock with cover crops
- Improve root health, helping stimulate biological components
- Activate some essential microorganisms so that the soil is in optimal condition.
When these cover crops break down, the organic matter that is generated manages to bring fertility to the soil by improving some of its properties, such as greater water retention capacity in periods of drought conditions, a stronger structure and increased performance of products including legumes and peas.
Another benefit that comes from using this type of crop is that they manage to capture nitrogen from the air and transfer it to the land. Did you know that nitrogen is vital to crop growth? Well, along with phosphorus and potassium, it is one of the main macro elements for plant nutrition, not only since it helps crops grow better and healthier, but also because it provides additional minerals in the form of nitrates.
What happens when the soil is damaged?
When it comes to using cover crops, there are other benefits that are critical for the sustainability of the land for agriculture, such as the fact that they are ideal when unexpected floods or storms have occurred since they can help recover fields that have been damaged by these adverse weather events.
Some of the benefits that come from using these cover crops for deteriorated soils include:
- Their protection
- Their structure improves
- Unnecessary nutrients are eliminated
- Nitrogen is fixed on the surface more efficiently
- They promote the best management of the moisture of the land
- They allow to include a good dose of life into the biology of the soil
All these benefits are factors that certainly contribute to recover the stability that the soils used to have before they were affected so that they can be reused for planting.
It is worth mentioning that in order for the soil to be classified as healthy, there needs to be a green element with the capacity to grow most of the year and as a result of that comes one of the most important reasons to use cover crops that contribute to protect and feed the agricultural land, especially for arbuscular mycorrhizal fungi that help take advantage of the sunlight and carbon dioxide available for biomass production for the system of the soil.
When there are no cover crops, the soil is unprotected from an additional layer that shelters it from an excess of raindrops that could erode it by causing the formation of scabs on the surface, or on the contrary, the wind and sun that directly affect it can cause significant wear and tear of the land by causing water to evaporate faster than it should.
For example, in the case of a flood, the first concern that comes to the mind of farmers is the fact that they want the soil to dry as soon as possible; however, having cover crops is recommended so their residues prevent moisture from dissipating abruptly, further damaging the integrity of the soil.
Benefits of cover crops on corn plantations
There are specific cases such as corn plantations where the crop can be lost as a result of hail or flooding, so using cover crops is a viable option to help absorb the nitrogen and replenish it biologically, before it is lost by leaching.
According to Soil Quality – Vocabulary – Terms and Definitions relating to the Protection and pollution of the soil (1963), leaching is basically the “phenomenon of displacement of soluble or dispersible substances (such as clay, salts, iron, humus) caused by the movement of water within the soil and is therefore characteristic of wet climates.”
Cover crops help release nitrogen while carbon is added to the system of the soil once it decomposes. In the absence of such crops, there is a risk that the likelihood of leaching will increase since there isn’t a plant that can grow to take advantage of that nitrogen, and also because the soils will be wetter than recommended.
When it comes to using cover crops to cultivate legumes, they should be inoculated first with the right product for each species as this will help guarantee that nitrogen is fixed and thus can perform its functions for the benefit of the plantation.
Over time, cover crops have become popular not only for the benefits we already mentioned, but also for their incredible ability to eliminate weeds, significantly reducing the need to use chemicals such as herbicides. They are an ideal choice for sustainable development.