Which devices are suitable for clover grass?

One of the key tasks on organic farms is the proper incorporation of clover grass, which is essential for saving water, preventing weeds, and allowing for mechanical weed control in the subsequent crop. What equipment is suitable for this task?

Clover grass is a staple in crop rotation on organic farms, making its incorporation a standard practice. While using a plow is the traditional method and creates favorable conditions for the next sowing, there are alternative solutions that conserve water, prevent sudden nitrogen mineralization, support soil life, and suppress competing plants. These alternative methods involve working the soil extremely shallowly using various techniques such as wide shares, horizontally rotating discs, or horizontally turning shafts. Which technique proves most effective in practical application?

Is a working depth of 2 cm achievable?

Clover grass stands can bind significant amounts of nitrogen, which is crucial for the nitrogen supply of the crop rotation on organic farms. Incorrect crop rotation planning or soil cultivation after clover grass can lead to unproductive nitrogen losses and the risk of nitrogen leaching into groundwater. These factors alone justify considering the method of clover grass incorporation. In addition, there is the task of handling soil water reserves as gently as possible, a task that a plow cannot fulfill.

However, equipment designed for very shallow soil cultivation can meet this requirement, provided they actually maintain the required depth of only 2 cm for the first pass. Whether these values are more aspirational than real was demonstrated in a presentation by the Agricultural Chamber of North Rhine-Westphalia at the Lienemann organic farm in Dorsten-Lembeck.

Breaking the capillaries to stop water evaporation is crucial. It is important to loosen the soil as little as possible to avoid accelerating mineralization, safely cut the clover grass under the vegetation cone to prevent regrowth, separate organic matter from the soil, and place it in small "portions" on the surface to dry out, making it easier for mechanical weed control in the subsequent crop. This cannot be achieved in a single pass; three to four passes are necessary.

Two-four-six method

Jan Wittenberg, the factory representative of machine manufacturer Treffler and an organic farmer himself, recommends the sequence of minus two, minus four, minus six for consecutive work steps. This sequence refers to the depth of work in centimeters for each pass. This ensures that the shares always work against firm ground and cut cleanly. Shares working in an already loosened layer only push the soil in front of them and no longer cut the vegetation.

The consequence of this method is that the first pass, for example, leaves untreated strips in wheel tracks. However, this is intentional and will be rectified with the second pass, added the factory representative.

Furthermore, this system promises success in managing water reserves. With the first pass, capillaries are cut, and water is retained in the subsoil. Following the final pass, crops like corn have direct access to moist soil.

Weed control with shallow cultivation

In addition, shallow cultivation offers advantages over plowing in weed control. Instead of burying weeds and seeds, which exacerbates the problem, the equipment creates a so-called false seedbed. Seeds are encouraged to germinate and then removed with the following pass.

It is crucial that the tools do not mix but "sort" the soil. Organic matter should be on the surface after the pass, allowing it to dry out and not hinder the germination of the subsequent crop or mechanical weed control.

This effect is achieved by the tools throwing the soil and organic matter "up" during cultivation, while a harrow supports the sorting.

Grubbers for clover grass

Treffler TGA

The Treffler attachment grubber "TGA," with a leaf-sprung Hardox share handle and serrated carbide share, has produced very good cultivation results. The share handle hardly deviates laterally, and the shares cut cleanly, creating a level cutting surface with a row spacing of 22 cm.

An elaborate chassis is responsible for maintaining the working depth. In the 5.60 m version, it consists of two tandem and two bogie wheels in front of the shares. The final harrow ensures the desired sorting effect.

ActiCut

The "ActiCut" from 4Disc undercuts the plants with ten rotating cutting discs in the 3 m version. They are angled about 5° lower at the front than at the back to pull them into the ground, with only a small part of the disc cutting. This prevents smearing layers and keeps the soil porous. The discs overlap about 6 cm and rotate at 60 rpm. The oil requirement for the ten discs is approximately 20 l/min.

The compact design and hydraulic power transmission from the tractor to the attachment ensure a smooth operation, good depth control, and reliable plant cutting.

Einböck Razor

In contrast to Treffler TGA, Einböck's new "Razor" grubber uses less stable share handles. The "Herkules tines," supplemented with reinforcement springs, are designed to avoid smearing layers through slight lateral movements. The Razor is still in the pre-production stage and is expected to be presented at Agritechnica.

The 20 cm wide shares are distributed over five beams, creating a row spacing of 15 cm. Front and rear support wheels are provided for depth control. A roller can also be placed in front of the harrow to take over depth control. The working horizon was as shallow as with Treffler, but seemed slightly less even.

Lyckegard Kvickfinn

With a combination of a three-beam grubber and a subsequent rotor, the Lyckegard "Kvickfinn" aims to meet the requirements for the perfect clover grass incorporation. The ten spring tines of the 2.80 m machine are equipped with 35 cm wide goosefoot shares.

The following rotor tines only reach as far into the ground as the shares work and throw the mix of soil and plant residues backward and upward. This reinforces the desired sorting effect so that the organic matter ends up safely on the surface. Lyckegard specifies the power requirement for the 1.6 t heavy machine as 80 to 150 PS.