Regenerative agriculture: techniques and equipment

The regenerative agriculture movement has emerged out of a growing awareness of the damage caused by the intensive use of agricultural land. We have already discussed this issue and how such an approach can lead to greater sustainability in agricultural production.  

We will now take a closer look at how regenerative practices can be implemented on a farm. How should the soil be managed? What equipment is needed?

Regenerative agriculture aims to restore the health of agricultural ecosystems by improving soil fertility, increasing biodiversity and minimising the use of external inputs such as fertilisers and pesticides. Soil management - tillage and the equipment used - is critical to achieving these goals.  

Starting with the basics: conservation tillage

To maintain soil structure and moisture and reduce soil loss through erosion, regenerative agriculture favours conservation tillage, defined as any system that leaves at least 30% of the surface covered with crop residues after sowing. There are three levels of conservation tillage:  

1. Non-tillage

2. Minimum Tillage

3. Strip Tillage

Special machines, called no-till seed drills, are used for the no-tillage. These seed drills are designed to sow directly into the previous crop residue. No ploughing or other soil preparation is required. They are usually combined machines, with discs or tines. They are fitted with special pre-sowing equipment so that crop residue can be removed, the furrow cut, seed placed and the furrow covered, all in one go. This helps to preserve the natural structure of the soil, reduce erosion and desertification, build up organic carbon in the soil and improve water management.

• Benefits: reduces erosion and compaction, increases water holding capacity, improves CO₂ storage, reduces the number of operations and time spent in the field
• Disadvantages: requires specific equipment and expertise, does not contain spontaneous growth, can cause cracking, not suitable for all soils  

Minimum tillage consists of carrying out superficial tillage (10-15 cm) without turning over the soil and only partially burying the crop residues with the harrow. This practice makes it possible to break up clods and surface crusts mainly caused by traffic in the field, and to cut crop residues without burying them, thanks to the high forward speed (8-12 km/h).  

• Benefits: reduces erosion and compaction, increases water holding capacity, breaks up residues, improves CO₂ storage, reduces the number of operations and time spent in the field
• Disadvantages: requires specific equipment and expertise, cannot bury residues, not suitable for all soils

Strip tillage consists of working the soil in strips, along the seeding rows, leaving the future inter-row intact. Tillage is shallow (10-15cm) and affects 25-45% of the total area. This type of tillage requires special equipment known as strip tillers and benefits from modern telemetry systems for tillage planning and managing.

• Benefits: reduces erosion and compaction, increases water holding capacity, breaks up residues, improves CO₂ storage, reduces the number of operations and time spent in the field
• Disadvantages: requires specific equipment and expertise, cannot bury residues, not suitable for all soils

Transitioning from a conventional to a conservative approach: how to prepare the soil

During the transition from the conventional to the conservative approach, if there is excessive soil compaction - including subsoil compaction and the risk of water stagnation - subsoiling may be necessary. This consists of loosening, lifting, and aerating the soil at 80-100cm depth while leaving the surface structure intact. Subsoilers can be used for this. Subsoiling is also useful when implementing keyline design: the soil is worked according to a specific design to optimise water distribution at depth.

• Benefits: reduces erosion and compaction, increases water holding capacity, improves CO₂ storage, aerates the soil at depth and loosens compacted subsoil where present
• Disadvantages: requires specific equipment and expertise, cannot bury residues

Changing weed management

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In regenerative agriculture the control of weeds is achieved by mechanical means. While conservation tillage preserves soil structure and increases soil fertility, it is less effective in controlling weeds. Different machines can be used for mechanical control.

• Tine or weed harrows allow weed control without excessive soil disturbance. They can be set to work at different depths and are useful for maintaing soil structure.

• Rod Weeder: used in pre-seeding, the rod weeder consists of a rigid rod inserted just below the soil surface; as it is pulled, the rod uproots weeds and improves seedbed preparation. It works just below the soil surface, so disturbance to the soil structure is minimal.